Binds low density lipoprotein /LDL, the major cholesterol-carrying lipoprotein of plasma, and transports it into cells by endocytosis. In order to be internalized, the receptor-ligand complexes must first cluster into clathrin-coated pits. Forms a ternary complex with PGRMC1 and TMEM97 receptors which increases LDLR-mediated LDL internalization (PubMed:30443021) (Microbial infection) Acts as a receptor for hepatitis C virus in hepatocytes, but not through a direct interaction with viral proteins (Microbial infection) Acts as a receptor for Vesicular stomatitis virus (Microbial infection) In case of HIV-1 infection, may function as a receptor for extracellular Tat in neurons, mediating its internalization in uninfected cells (Microbial infection) Acts as a receptor for Crimean-Congo hemorrhagic fever virus (CCHFV) (Microbial infection) Acts as a receptor for many Alphavirus, including Getah virus (GETV), Ross river virus (RRV) and Semliki Forest virus

LRP4 is an entry receptor for multiple encephalitic alphaviruses.

Abstract: Encephalitic alphaviruses, including Eastern equine encephalitis virus (EEEV), cause severe neurological disease with high mortality rates, and thus are a public health threat. Although members of the low-density lipoprotein receptor (LDLR) family, including VLDLR, LRP8 (ApoER2), and LDLR recently were identified as receptors for EEEV, residual infection in receptor-deficient cells suggests that additional entry factors exist. Using a CRISPR-based activation screen, we identified LDLR-related protein 4 (LRP4) as a candidate entry factor for EEEV and several related alphaviruses (Western equine encephalitis, Semliki Forest, and Sindbis viruses). LRP4 mediates viral attachment and internalization, and its ligand-binding domain binds directly to virions. Soluble LRP4 decoy proteins potently inhibit EEEV infection in primary mouse neuronal cells, male mice, and human brain organoids, suggesting possible therapeutic applications. Mammalian and avian LRP4 orthologs demonstrate conserved functions in promoting EEEV infection, supporting a possible role in its host range of infection and transmission. Our findings establish LRP4 as a shared entry receptor for multiple alphaviruses and expand our understanding of alphavirus tropism, pathogenesis, and countermeasure development.

NOD1 ligand FK565 promotes atherogenesis and accumulation of NOD1

Abstract: Nucleotide-binding oligomerization domain-containing protein (NOD)1 is an intracellular pattern recognition receptor that initiates immune responses upon ligation of molecules such as bacterial peptidoglycan containing a D-glutamyl-meso-diaminopimelic acid (iE-DAP) moiety. NOD1 ligation has been shown to promote vascular inflammation and atherosclerosis. In this study, we investigate the functional role of NOD1 in atherosclerotic plaques and characterize the vascular cells responsible for NOD1 expression and function. NOD1 was mainly expressed in a subtype of vascular smooth muscle cells (SMC) in human atherosclerotic lesions. In ex vivo cultures, human endarterectomy specimens reacted to NOD1 ligand by activation of mitogen-activated protein kinase (MAPK) p38 pathway, leading to cytokine expression. Levels of NOD1 mRNA were higher in carotid endarterectomy specimens obtained from symptomatic patients compared to asymptomatic ones. NOD1+ SMC were also found in arteries of atherosclerosis-prone Ldlr-/- mice. Challenging these mice with a NOD1 agonist resulted in transmural vascular inflammation, severe arterial damage, accelerated atherogenesis throughout the aorta, and evidence of occlusive coronary artery disease. In rats, mechanic injury to carotid arteries promoted NOD1+ SMC expansion and neointima formation. In vitro, neointima derived NOD1+ SMCs responded to NOD1 ligand exposure by enhanced migration, increased iNOS+ cells and amplified CCL5 production. Our findings show that NOD1 promotes vascular inflammation, vascular injury responses and atherosclerosis by acting on a NOD1+ subtype of SMC.

Flow-mediated endothelial remodeling and inflammation drive developmental vascular susceptibility in ldlr loss of function.

Abstract: Atherosclerosis, the leading cause of cardiovascular disease, is associated with aberrant lipid metabolism, endothelial dysfunction, and chronic inflammation, yet its early manifestations and mechanisms remain incompletely understood. As low-density lipoprotein receptor loss of function is the most common monogenic cause of atherosclerosis, we employed low-density lipoprotein receptor knockout (ldlr-/-) zebrafish to investigate the developmental origins of atherosclerotic cardiovascular disease. Single-cell RNA-sequencing under differential flow conditions in embryonic ldlr-/- zebrafish identified a population of disproportionately stressed endothelial cells marked by overexpression of heat shock protein 70 (hsp70). Hsp70 is induced in stressed endothelial cells in a flow-dependent manner in zebrafish and a subset of human endothelial cells, and its activation is associated with disrupted remodeling angiogenesis in vivo. Genetic and pharmacological studies demonstrated that hsp70 upregulation inhibits vascular apoptosis and ciliogenesis, leading to altered angiogenic remodeling. Concurrently, pro-inflammatory processes, including enhanced myelopoiesis and thrombogenicity, are amplified at early stages in ldlr-/- zebrafish, which also exhibit impaired regenerative angiogenesis and heightened neutrophil recruitment post-vascular injury. Our findings reveal how abnormalities in flow-mediated endothelial remodeling and inflammation converge during embryogenesis to drive vascular susceptibility to hemodynamic and other stressors in ldlr loss of function.

Macrophage EHD1 Promotes Inflammation and Stabilizes Sortilin to Accelerate Atherosclerosis.

Abstract: Macrophages are key players in the pathogenesis of atherosclerosis. They trigger immune responses through their cell-surface receptors. However, how macrophages regulate those receptors in response to proinflammatory stimuli is not completely understood. Endocytic membrane trafficking involving receptor internalization, followed by endosomal transport and recycling of the internalized receptors, plays essential roles in balancing cell-surface receptors to meet cellular needs. Here, we explored the role of the endocytic regulator EHD (c-terminal Eps15 homology domain) 1 in immune responses in macrophages and determined its contribution to atherosclerosis progression. EHD1 expression profiles in mouse and human plaques were determined by single-cell RNA sequencing and immunofluorescence staining. Bone marrow transplantation by transplanting bone marrow cells from Ehd1-/- or littermate wild-type mice to irradiated Ldlr-/- mice was performed to determine the effect of EHD1 deletion on atherosclerosis progression. In vitro mechanistic studies, including inflammation signaling and endocytosis assays, were performed in bone marrow-derived macrophages. EHD1 expression in macrophages is enhanced as atherosclerosis progresses in both mice and humans. Histological analysis of aortic root sections from bone marrow transplantation mice showed that EHD1 deletion reduces lesion size. Single-cell RNA sequencing of aortic CD (cluster of differentiation) 45+ cells demonstrated that EHD1 deletion attenuates proinflammatory responses and cell-cell interactions. Mechanistic studies revealed that EHD1 accelerates the endocytic recycling of TNFR2 (tumor necrosis factor receptor 2) and activates NF-κB (nuclear factor kappa B), leading to increased expression of inflammatory cytokines. Moreover, EHD1 interacts with retromer and stabilizes sortilin, a retrograde cargo of retromer and a risk factor for atherosclerosis. EHD1 promotes inflammation by enhancing TNFR2-NF-κB signaling and stabilizing sortilin, leading to accelerated atherosclerosis. Our study reveals novel roles for EHD1-mediated membrane trafficking in macrophage function and paves the way to innovative therapeutic strategies that aim to address dysregulated membrane trafficking in atherosclerosis.

Perk Is Dispensable for Smooth Muscle Cell Phenotype Switching in Atherosclerosis.

Arteriosclerosis, thrombosis, and vascular biology

Abstract: Smooth muscle cell (SMC) derived cells form the bulk of cells in atherosclerotic lesions and modulate lesion stability and cardiovascular disease outcomes. Unfolded protein response (UPR) markers, thin fibrous caps, and inflammation correlate with human lesion instability and rupture. In mice, UPR drives macrophage and endothelial apoptosis and inflammation, but its impact on lesion stability through SMC modulation is debated. The UPR protein Perk (protein kinase RNA-like ER kinase) was recently shown to drive SMC modulation in vivo, suggesting that depletion of SMC Perk may regulate lesion stability. SMC Perk was deleted from SMC-lineage-traced adult Ldlr-/- hypercholesterolemic mice. Lesions were scored for features of lesion stability and analyzed for differential expression at the single-cell level. Perk knockdown in primary murine SMCs was used to study Perk's effect on SMC modulation in vitro. UPR marker expression in human carotid lesions was assessed for UPR markers through scRNA-seq, bulk RNA-seq, and Xenium spatial transcriptomics. SMC Perk deletion in adult atherogenic mice did not affect weight gain or serum cholesterol levels. Lesions from Perk knockout mice resembled Perk WT counterparts with similar progression, lesion stability features, and cell populations. Scoring of UPR activity and differential expression analysis found little UPR activity in SMC and smooth muscle-derived cell populations. Perk was not required for in vitro SMC modulation in atherogenic conditions. No correlation was found between UPR markers and lesion stability or symptomatic clinical presentation in human carotid lesions, and UPR markers were expressed primarily in infiltrating leukocytes rather than in SMCs and stromal cells. SMC Perk UPR does not play a significant role in atherosclerotic SMC modulation, disease progression, or features of lesion stability in mice. Similarly, expression of markers of the Perk UPR pathway in humans does not correlate with human carotid lesion stability or clinical presentation.


Crucial player in the regulation of plasma cholesterol homeostasis. Binds to low-density lipid receptor family members: low density lipoprotein receptor (LDLR), very low density lipoprotein receptor (VLDLR), apolipoprotein E receptor (LRP1/APOER) and apolipoprotein receptor 2 (LRP8/APOER2), and promotes their degradation in intracellular acidic compartments (PubMed:18039658). Acts via a non-proteolytic mechanism to enhance the degradation of the hepatic LDLR through a clathrin LDLRAP1/ARH-mediated pathway. May prevent the recycling of LDLR from endosomes to the cell surface or direct it to lysosomes for degradation. Can induce ubiquitination of LDLR leading to its subsequent degradation (PubMed:17461796, PubMed:18197702, PubMed:18799458, PubMed:22074827). Inhibits intracellular degradation of APOB via the autophagosome/lysosome pathway in a LDLR-independent manner. Involved in the disposal of non-acetylated intermediates of BACE1 in the early secretory pathway (PubMed:18660751). Inhibits epithelial Na(+) channel (ENaC)-mediated Na(+) absorption by reducing ENaC surface expression primarily by increasing its proteasomal degradation. Regulates neuronal apoptosis via modulation of LRP8/APOER2 levels and related anti-apoptotic signaling pathways

Evaluation of DeepSeek-Generated Biochemistry Clinical Cases for Teaching Purpose.

Biochemistry and molecular biology education : a bimonthly publication of the International Union of Biochemistry and Molecular Biology

Abstract: To overcome limitations in traditional case-based teaching, this study developed an AI-driven workflow using DeepSeek to generate contemporary, interdisciplinary clinical biochemistry cases. Through human-AI collaboration, eight structured cases covering key topics such as carbohydrate and lipid metabolism were created, each including a clinical description, molecular mechanisms, and Q&A, followed by instructor review. Fifteen medical students and 15 instructors evaluated the cases using a 5-point Likert scale across multiple dimensions, while student performance was compared between a group using AI-generated cases and a control group. The AI generated each case in 10-15 min, significantly faster than manual development. Cases presented a logical progression from molecular mechanism to clinical management and incorporated recent advances such as CRISPR and PCSK9 inhibitors. Content integration received the highest ratings, though instructors scored pedagogical applicability lower. Error analysis indicated that AI excelled in maintaining logical consistency, whereas human reviewers enhanced precision in clinical details. Students who used the AI-generated cases achieved significantly higher examination scores than the control group (p < 0.05). In conclusion, DeepSeek-generated cases are efficient, interdisciplinary, and innovative. Human review remains essential for ensuring clinical rigor, particularly in nuanced scenarios. This collaborative approach enhances both the efficiency of case development and the educational quality of biochemistry teaching materials.

Targeting PCSK9 in Vascular Smooth Muscle Cells: An Effective Strategy to Suppress Ferroptosis and Attenuate Abdominal Aortic Aneurysm Progression.

Abstract: Abdominal aortic aneurysm (AAA) lacks effective pharmacotherapy. This study examines whether proprotein convertase subtilisin/kexin type 9 (PCSK9) drives ferroptosis in vascular smooth muscle cells (VSMCs) and whether its pharmacological degradation mitigates disease progression. PCSK9 is enriched in VSMCs of human AAA and in murine models induced by PPE or Ang II. SMC-specific PCSK9 overexpression (PCSK9SMC OE) increases aortic diameter, aggravates elastin fragmentation and collagen deposition and elevates MMP2/9 expression. Within aortic lesions, PCSK9SMC OE enhances iron accumulation and lipid peroxidation while reducing glutathione GPX4, consistent with ferroptosis. In primary VSMCs, PCSK9 overexpression suppresses GPX4 and glutathione, increases malondialdehyde and Fe2+ levels and impairs viability, whereas PCSK9 knockdown attenuates Ang II-induced ferroptosis. Mechanistically, PCSK9 triggers ferritinophagy, as shown by decreased ferritin heavy chain-1 (FTH1) and nuclear receptor coactivator-4 (NCOA4), an increased LC3-II/I ratio and enhanced FTH1-LAMP1 colocalisation. Autophagy inhibition with bafilomycin A1 blocks Fe2+ accumulation and rescues ferroptotic indices. The cell-permeable peptide Cadd4 promotes PCSK9 degradation, restores FTH1 and NCOA4 and suppresses ferroptosis in VSMCs. In PPE and Ang II models, Cadd4 reduces aortic dilation, preserves medial structure and normalises ferroptosis and ferritinophagy markers. PCSK9 drives ferritinophagy-dependent ferroptosis in VSMCs, and Cadd4 represents a promising therapeutic strategy for AAA.

Context-dependent regulation of endothelial inflammation and atherosclerosis by endothelial microRNA-33.

Abstract: Atherosclerosis arises through the metabolic and inflammatory perturbation of numerous cells, including immune cells and endothelial cells (ECs). microRNA-33 (miR-33) regulates lipid metabolism and inflammatory responses of immune cells, but the impact of miR-33 on atherosclerosis progression has mixed effects, pointing to context- and cell-type-specific functions. Notably, the role of EC miR-33 in atherosclerosis remains unexplored, despite the central involvement of metabolic and inflammatory pathways in EC function. We sought to determine the definitive role of EC miR-33 in atherosclerosis progression. We generated mice with an inducible EC-specific miR-33 knockout (iECKO), followed by PCSK9-AAV8 injection and western diet feeding. Detailed plaque analyses and scRNAseq were performed. For acute inflammation, we analyzed TNFα-mediated leukocyte recruitment in the air pouch model. In vitro approaches included the culture of human aortic ECs to analyze gene expression under inflammatory and lipid-laden conditions with miR-33 mimicry. iECKO mice showed accelerated lesion initiation, but this effect did not persist in advanced atherosclerosis, which is likely due to chronic hypercholesterolemia-driven downregulation of miR-33 that masks its deletion at later stages. Transcriptomic analyses revealed that cholesterol loading alters EC responses to inflammation, which can be partially rescued by miR-33 mimicry. Accordingly, iECKO mice exhibited heightened sensitivity to acute, normocholesterolemic inflammation, which is paralleled with regulation of E-selectin levels. Our work underscores the nuanced effects of miR-33 manipulation and highlights how well-described regulators of atherosclerosis progression may have unique cell type- and disease stage-dependent roles. Additionally, our work further implicates miR-33 as a regulator of EC function and identifies a new potential role in acute inflammation via E-selectin regulation.

Cholesterol metabolism in immune cells: From mechanisms to therapeutic opportunities.

Abstract: All immune cells engage in cholesterol metabolism, which generates a spectrum of bioactive metabolites that mainly include cholesterol itself, its biosynthetic intermediates, and oxidized or sulfated derivatives. These metabolites regulate not only cellular metabolism but also immune signaling. In addition, several functional proteins within cholesterol metabolic pathways exert non-canonical signaling functions that shape immune cell responses. Distinct immune cell types adopt specialized cholesterol metabolic programs tailored to their functional demands, and these programs are further influenced by physiological factors such as diet and aging. In human disease, immune cell cholesterol metabolism is frequently dysregulated, which highlights metabolic intervention as a promising therapeutic strategy. Accordingly, the repurposing of established metabolic drugs such as statins and PCSK9 inhibitors is gaining momentum, alongside the identification of additional therapeutic targets. A deeper understanding of how cholesterol metabolism governs immune responses will advance fundamental immunology and accelerate the development of next-generation immunotherapies.

PROTAC-mediated PCSK9 degradation attenuates atherosclerosis and improves plaque composition via suppression of NF-κB/TNF-α pathway.

Abstract: Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a critical therapeutic target for managing hyperlipidemia and atherosclerosis. We developed Cadd4, a synthetic proteolysis-targeting chimera (PROTAC) engineered to selectively induce proteasomal degradation of the PCSK9 protein. In this study, we investigate Cadd4's anti-atherosclerotic properties and concurrently evaluate the feasibility and safety of its long-term therapeutic administration. Cadd4-mediated PCSK9 degradation was assessed in mouse monocyte-macrophage leukemia cells(RAW264.7), mouse aortic vascular smooth muscle cells (MOVAS) and human umbilical vein endothelial cells (HUVECs) using immunofluorescence. Its anti-inflammatory effects were examined in lipopolysaccharide (LPS)-stimulated cells via quantitative real‑time PCR (qRT-PCR) and western blot. In vivo efficacy was assessed in apolipoprotein E-deficient (ApoE-/-) mice maintained on a high-fat diet (HFD). Animals received intraperitoneal injections of Cadd4 (20 mg/kg every two days) or subcutaneous injections of alirocumab (3 mg/kg weekly) for 12 consecutive weeks. Cadd4 induced dose-dependent PCSK9 degradation in all three cell types tested and significantly attenuated LPS-induced inflammatory responses. Notably, a 2-week intraperitoneal administration of Cadd4 led to a marked reduction in PCSK9 expression in both the liver and aorta of treated mice. In HFD-fed ApoE-/- mice, 12-week administration of Cadd4 significantly decreased atherosclerotic plaque area, enhanced collagen deposition within plaques and suppressed intra-plaque inflammation. Importantly, compared with alirocumab, Cadd4 demonstrated superior efficacy in suppressing matrix metalloproteinase (MMP) expression and increasing collagen content, effects that are likely mediated via inhibition of the NF-κB/TNF-α signaling pathway. Of note, Cadd4 mediated PCSK9 modulation did not alter plasma lipid profiles in this model. Collectively, these anti-atherosclerotic effects underscore the lipid-independent anti-inflammatory activity and plaque composition-improving capacity of Cadd4. Cadd4 potently induces PCSK9 degradation in arterial tissues, mitigates atherosclerotic progression and improves plaque composition via lipid-independent inhibition of the NF-κB/TNF-α pathway. These findings underscore the therapeutic promise of Cadd4 as a candidate for managing atherosclerotic cardiovascular disease.


Apolipoprotein B is a major protein constituent of chylomicrons (apo B-48), LDL (apo B-100) and VLDL (apo B-100). Apo B-100 functions as a recognition signal for the cellular binding and internalization of LDL particles by the apoB/E receptor

Century of Progress on the Structure of APOB-100 in Atherogenic Lipoproteins.

Abstract: APOB-100 (apolipoprotein B100) is the obligate structural protein of very low-density lipoprotein (VLDL), intermediate density lipoprotein, and low-density lipoprotein (LDL), with each atherogenic particle containing a single copy. Because circulating APOB concentration reflects particle number, it has emerged as a clinically important marker that may outperform LDL cholesterol in cardiovascular risk prediction. Historically, the large size, lipid dependence, and conformational diversity of APOB have hindered a detailed structural understanding. However, recent advances in cryo-electron microscopy and integrative modeling have transformed this landscape, yielding near-atomic models of APOB organization on human LDL and defining the structural basis for receptor recognition. This review traces the evolution of APOB structural concepts from its discovery as the main LDL scaffold to contemporary cryo-electron microscopy-derived architectures. The new structures reveal an extended scaffold that encircles the particle, accommodates large changes in lipid cargo, and presents multiple interaction surfaces for the LDL receptor. The new models reconcile decades of mutagenesis, antibody mapping, and cross-linking data and provide a mechanistic framework for understanding familial hypercholesterolemia variants, receptor binding stoichiometry, and the structural transitions that occur during VLDL to LDL remodeling. Despite these advances, intrinsic heterogeneity in particle size, lipid composition, and protein conformation imposes fundamental limits on achievable resolution, and we argue that APOB should be viewed as a dynamic structural ensemble rather than a single static molecule. Future work will require integration of structural models with targeted biochemical studies to define cooperative receptor binding mechanisms, structural determinants of remnant clearance, and the basis for association with exchangeable apolipoproteins and lipolysis regulators. Extending cryo electron microscopy to LDL subpopulations like lipoprotein(a) and VLDL remnants promises to establish new frameworks for linking APOB architecture to lipoprotein metabolism and cardiovascular disease.

Antibody E06 and the Role of Oxidized Phospholipids in Atherogenesis and Inflammation.

Abstract: Oxidized phospholipids (OxPL) are generated at sites of oxidative stress and tissue injury, where they function as prototypic danger-associated molecular patterns that trigger inflammation, cell death, and tissue remodeling. The natural IgM antibody E06, and derivative formats such as E06-scFv, recognize the phosphocholine epitope on OxPL but not on native phospholipids, providing powerful tools to probe the biology of OxPL across cardiovascular and noncardiovascular disease. In this review, we summarize experimental and translational evidence implicating OxPL as mediators of atherogenesis, myocardial ischemia-reperfusion injury, nonalcoholic steatohepatitis and hepatocellular carcinoma, bone loss, lung fibrosis and acute lung injury, sepsis, neuroinflammation, and pain. In multiple murine models, genetic or passive approaches that express or deliver E06-based constructs neutralize OxPL, attenuate inflammation, improve tissue function, and reduce lesion burden, establishing OxPL as an actionable driver rather than a passive byproduct of oxidative stress. We further highlight how E06 has been leveraged to develop sensitive immunoassays for OxPL on apoB-containing lipoproteins and on Lp(a) (lipoprotein[a]; OxPL-apo[a]). These biomarkers consistently associate with incident and recurrent cardiovascular events and link OxPL biology to human lipoprotein metabolism, particularly the preferential enrichment of OxPL on Lp(a). We review emerging data on how established and novel therapies, including statins, PCSK9 (proprotein convertase subtilisin/kexin type 9) inhibitors, lipoprotein apheresis, and Lp(a)-targeted antisense and RNA-based agents, modulate OxPL, and discuss how these interventions may help test the OxPL hypothesis in outcomes trials. Finally, we outline key challenges and opportunities for translating OxPL-directed strategies to the clinic, including issues of specificity, immunogenicity, timing, and patient selection. Collectively, these insights position OxPL and its selective neutralization by E06-like antibodies as a unifying mechanism and promising therapeutic target across diverse inflammatory and cardiometabolic diseases.

Peptide-mediated delivery of an α-synuclein-targeting antisense oligonucleotide: Pharmacokinetics, safety, and central nervous system efficacy in a synucleinopathy model.

Drug metabolism and disposition: the biological fate of chemicals

Abstract: Effective blood-brain barrier penetration is a major challenge for antisense oligonucleotide (ASO) therapies targeting neurodegenerative diseases. We utilized an 11-amino acid peptide derived from apolipoprotein B (ApoB11) that binds the low-density lipoprotein receptor to cross the blood-brain barrier, to deliver an ASO systemically to the central nervous system (CNS) and suppress targeted transcripts in neurodegenerative disease models. This study evaluates the pharmacokinetics, CNS penetration, and therapeutic efficacy of ApoB11:2'-O-methyl ASO-α-Syn, an ASO for α-synuclein (α-Syn) suppression in synucleinopathies. After a single intraperitoneal injection (2 mg/kg) in C57BL/6 mice, ApoB11:ASO-α-Syn showed robust brain penetration, reaching peak concentrations (maximum concentration [Cmax] = 0.14 nmol/mg) at 1.5 hours and persisting at high levels over the 96-hour observation period, indicating prolonged CNS retention. Immunofluorescence confirmed widespread uptake in neurons and endothelial cells. The ASO also accumulated in the liver (Cmax = 419.5 nmol/mg, t1/2 = 104.9 hours), consistent with receptor-mediated uptake. Acute and subacute toxicity studies revealed no systemic toxicity at the highest nonlethal dose (32 mg/kg). In a mouse model of dementia with Lewy bodies overexpressing human α-Syn, ApoB11:ASO-α-Syn reduced α-Syn mRNA and protein levels in the hippocampus and cortex by ∼50% at 16 mg/kg, a reduction that is biologically meaningful based on human genetic evidence (SNCA duplications/triplications) and preclinical studies. These results demonstrate that ApoB11 is an effective ASO carrier for CNS delivery, and that partial α-Syn reduction is expected to have disease-relevant effects, supporting its potential as a therapeutic strategy for synucleinopathies. SIGNIFICANCE STATEMENT: This study demonstrates that systemically delivered ApoB11-conjugated antisense oligonucleotides effectively cross the blood-brain barrier, achieve sustained central nervous system retention, and produce a biologically meaningful reduction (∼50%) in α-synuclein expression in a transgenic mouse model of synucleinopathy. These findings highlight a minimally invasive, peptide-mediated strategy for targeting neurodegenerative diseases and overcoming major delivery limitations of antisense oligonucleotide therapies.

Triazine Thiols Decrease Apolipoprotein B Secretion From Hepatocytes Through Inhibition of Human Carboxylesterase 1.

Cellular and molecular gastroenterology and hepatology

Abstract: Homozygous familial hypercholesterolemia is an autosomal genetic disorder that generates increased levels of low-density lipoproteins in the serum. Elevated low-density lipoprotein results in hypercholesterolemia leading to potentially fatal cardiovascular disease. Patients with homozygous familial hypercholesterolemia are often refractory to standard cholesterol-lowering treatments. Some available pharmaceuticals developed specifically for homozygous familial hypercholesterolemia can elevate hepatic lipid levels and in other cases have limited accessibility. Previously, we identified a family of triazine thiol compounds that effectively reduce apolipoprotein B-100 secretion by hepatocytes. In mice with humanized livers, triazine thiols effectively lowered serum cholesterol, triglycerides, low-density lipoproteins and lipoprotein(a). Despite their effectiveness, the mode of action of triazine thiols was unknown. Affinity-based mass spectrometry, biochemical assays, molecular modeling, and gene-edited induced pluripotent stem cell-derived hepatocyte-like cells were used to identify and characterize the molecular target and mechanism of action of triazine thiols. Using affinity-based mass spectrometry, we identified Carboxylesterase 1 (CES1) as a triazine thiol binding protein. Biochemical assays demonstrated that triazine thiols are slow-binding, allosteric, covalent CES1-specific inhibitors. Molecular modeling identified a predicted binding site within CES1 near cysteine 390, and loss of this cysteine conferred resistance to triazine thiol-mediated inhibition. Moreover, hepatocyte-like cells derived from CES1-/- induced human pluripotent stem cells exhibited a significant reduction in APOB secretion, mimicking the effect of triazine thiol treatment. This study establishes triazine thiols as novel, highly specific carboxylesterase 1 inhibitors, providing insight into their mechanism and highlighting carboxylesterase 1 inhibition as an approach for treating hypercholesterolemia.

ApoA-I Dissociated From Human HDL Retains its Acceptor Properties in ABCA1-mediated Cholesterol Efflux From RAW 264.7 Macrophages in Coronary Artery Disease.

Frontiers in bioscience (Landmark edition)

Abstract: The significance of cholesterol efflux as a predictor of coronary artery disease (CAD) remains controversial. The intracellular cholesterol export via the ABCA1 transporter involves the acceptance of cholesterol by both lipid-free apolipoprotein A-I and high-density lipoproteins (HDL). An estimate of the efficiencies of two reactions is thus required. HDL from the plasma of 63 control and 76 male CAD patients was obtained by the precipitation of apoB-containing lipoproteins and denatured by urea. We measured apoA-I dissociation concomitant with HDL denaturation by agarose gel electrophoresis followed by immunodetection and the expression of 65 preselected genes in blood mononuclear cells by real-time PCR. The total cholesterol efflux capacity (CEC) of ATP-binding cassette transporter A1 (ABCA1)-mediated cholesterol efflux from RAW 264.7 macrophages, when preβ-HDL and α-HDL act as competitive inhibitors of each other for the binding to ABCA1 transporter, was measured with intact HDL and pre-denatured HDL as a source of lipid-free apoA-I. The phospholipid:apoA-I and cholesterol:apoA-I ratios in HDL from CAD patients were higher than those for control patients across the full range of plasma HDL-cholesterol levels. ApoA-I partitioned 1.5-fold higher into the water phase for HDL from CAD patients relative to controls. In CAD patients, the dissociation parameter D was inversely correlated with absolute and normalized per apoA-I phospholipid and cholesterol levels in HDL. For control patients, the D parameter was positively correlated with ABCA1 gene expression. For CAD patients, the D parameter was positively correlated with PLTP and inversely with CUBN and ALB gene expression. ApoA-I functionality in ABCA1-mediated cholesterol efflux from RAW 264.7 macrophages to lipid-free apoA-I generated from urea-induced HDL denaturation was similar for HDL from control and CAD groups. The retained CEC of lipid-free apoA-I in CAD may be masked by competition with α-HDL, which has a lower CEC, for ABCA1 binding to preβ-HDL. The enrichment of HDL with cholesterol and phospholipids may contribute to the increased apoA-I dissociation from HDL in CAD. Estimates of both lipid-free apoA-I and intact HDL may be a prerequisites for a detailed study of ABCA1-mediated cholesterol efflux, which could allow these apoA-I forms to be identified as CAD predictors.


Cystic fibrosis transmembrane conductance regulator

Epithelial ion channel that plays an important role in the regulation of epithelial ion and water transport and fluid homeostasis (PubMed:26823428). Mediates the transport of chloride ions across the cell membrane (PubMed:10792060, PubMed:11524016, PubMed:11707463, PubMed:12519745, PubMed:12529365, PubMed:12588899, PubMed:12727866, PubMed:15010471, PubMed:17036051, PubMed:1712898, PubMed:17182731, PubMed:19398555, PubMed:19621064, PubMed:22178883, PubMed:25330774, PubMed:26846474, PubMed:28087700, PubMed:8910473, PubMed:9804160). Possesses an intrinsic ATPase activity and utilizes ATP to gate its channel; the passive flow of anions through the channel is gated by cycles of ATP binding and hydrolysis by the ATP-binding domains (PubMed:11524016, PubMed:15284228, PubMed:26627831, PubMed:8910473). The ion channel is also permeable to HCO(3)(-); selectivity depends on the extracellular chloride concentration (PubMed:15010471, PubMed:19019741). In vitro, mediates ATP-dependent glutathione flux (PubMed:12727866). Exerts its function also by modulating the activity of other ion channels and transporters (PubMed:12403779, PubMed:22121115, PubMed:22178883, PubMed:27941075). Plays an important role in airway fluid homeostasis (PubMed:16645176, PubMed:19621064, PubMed:26823428). Contributes to the regulation of the pH and the ion content of the airway surface fluid layer and thereby plays an important role in defense against pathogens (PubMed:14668433, PubMed:16645176, PubMed:26823428). Modulates the activity of the epithelial sodium channel (ENaC) complex, in part by regulating the cell surface expression of the ENaC complex (PubMed:17182731, PubMed:17434346, PubMed:27941075). Inhibits the activity of the ENaC channel containing subunits SCNN1A, SCNN1B and SCNN1G (PubMed:17182731). Inhibits the activity of the ENaC channel containing subunits SCNN1D, SCNN1B and SCNN1G, but not of the ENaC channel containing subunits SCNN1A, SCNN1B and SCNN1G (PubMed:17182731, PubMed:27941075). May regulate bicarbonate secretion and salvage in epithelial cells by regulating the transporter SLC4A7 (PubMed:12403779). Can inhibit the chloride channel activity of ANO1 (PubMed:22178883). Plays a role in the chloride and bicarbonate homeostasis during sperm epididymal maturation and capacitation (PubMed:19923167, PubMed:27714810, PubMed:29393851)

Nasal Epithelial Organoids as Translational Platforms in Inflammatory, Infectious, and Precision Medicine Applications: A Systematic Review.

Abstract: Background/Objectives: The airway epithelium plays a central role in host defense, inflammatory signaling, and disease progression across infectious, inflammatory, and genetic respiratory disorders. Human nasal epithelial organoids have emerged as accessible and patient-specific in vitro platforms with increasing translational relevance. This systematic review aimed to critically evaluate the current evidence on nasal epithelial organoid models, focusing on donor characteristics, culture methodologies, differentiation strategies, and translational applications. Methods: A systematic search of PubMed/MEDLINE, Embase, Scopus, Ovid MEDLINE, and Cochrane Library was conducted for studies published between 1990 and April 2026. The review followed PRISMA guidelines and was structured according to the PICOTS framework. Eligible studies included in vitro experimental investigations using human-derived nasal epithelial organoids in infectious, inflammatory, or precision medicine contexts. Risk of bias was assessed using the QUIN tool. Results: Seventeen studies met the inclusion criteria. Applications clustered into three principal domains: infectious disease modeling, inflammatory and epithelial remodeling research, and cystic fibrosis precision medicine. Most studies employed expandable three-dimensional Matrigel-embedded organoids or organoid-derived air-liquid interface systems. Infection-focused studies demonstrated variant-specific viral replication dynamics and epithelial immune responses, while inflammatory models reproduced disease-associated differentiation and remodeling phenotypes. Cystic fibrosis oriented studies showed that organoid swelling and electrophysiological assays correlate with CFTR functional rescue and, in selected cases, clinical response. Methodological heterogeneity across protocols and outcome reporting precluded quantitative synthesis. Conclusions: Human nasal epithelial organoids represent versatile translational platforms bridging accessible patient-derived tissue and advanced airway disease modeling. Although variability in culture protocols and functional benchmarks limits standardization, these models hold significant promise for mechanistic investigation, therapeutic stratification, and precision medicine applications.

Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) Dysfunction in Human Diseases: Molecular Mechanisms and Pathophysiological Implications.

Abstract: Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) dysfunction is increasingly recognized as a key contributor to a broad spectrum of human diseases beyond classical cystic fibrosis (CF). CFTR is a cAMP-regulated chloride and bicarbonate ion channel expressed in both epithelial and non-epithelial tissues, where it regulates ion homeostasis, mucosal hydration, and cellular signaling. Both inherited CFTR mutations and acquired dysfunction resulting from environmental or inflammatory factors can disrupt these physiological processes and drive disease progression. Current evidence linking CFTR dysregulation to respiratory diseases, such as cystic fibrosis, chronic obstructive pulmonary disease (COPD), asthma, and HIV-associated airway disease, as well as cardiovascular, renal, neurological diseases, and cancer, is comprehensively discussed. Mechanistically, impaired CFTR function promotes oxidative stress, chronic inflammation, epithelial barrier dysfunction, altered mucociliary clearance, and dysregulation of signaling pathways, including NF-κB, TGF-β, PI3K/Akt, MAPK, and Wnt/β-catenin. In the context of HIV infection and cigarette smoke exposure, CFTR suppression is mediated in part by TGF-β signaling and miRNA-dependent mechanisms, resulting in compromised airway defense and increased susceptibility to pulmonary complications. Recent studies further demonstrate that CFTR dysregulation alters the expression of genes involved in fibrosis, inflammation, angiogenesis, and epithelial-mesenchymal transition (EMT). Notably, CFTR may act as either a tumor suppressor or a context-dependent oncogene, depending on tissue type and signaling milieu, highlighting its complex role in cancer biology. Advances in CFTR-targeted therapies, including potentiators, correctors, gene therapy, and combination approaches, have markedly improved outcomes in CF and may offer therapeutic potential for diseases associated with acquired CFTR dysfunction. We summarize the systemic consequences of CFTR dysregulation and the need for further mechanistic and translational research to clarify its role across diverse human diseases.

Vanzacaftor-Tezacaftor as an alternative therapeutic resource for the ETI-Resistant L467F-F508del Allele: Ex vivo prediction and exploratory clinical assessment.

Journal of cystic fibrosis : official journal of the European Cystic Fibrosis Society

Abstract: The triple combination of Elexacaftor/Tezacaftor/Ivacaftor (ETI) has revolutionized cystic fibrosis (CF) treatment; however, a subset of patients with eligible genotypes remains unresponsive. We previously identified the L467F-F508del complex allele as a cause of therapeutic failure, conferring a severe processing defect that renders the CFTR protein refractory to ETI. To address this unmet need, we evaluated the efficacy of the next-generation combination comprising Vanzacaftor/Tezacaftor (Vnz/Tez). We utilized primary human nasal epithelial (HNE) cells derived from six patients carrying the L467F-F508del complex allele and a minimal function mutation and monitored the clinical response of a patient treated with Vanzacaftor/Tezacaftor/Deutivacaftor (VTD) via compassionate use. Mechanistic validation was performed in CFBE41o- cells. In patient-derived HNE models, treatment with Vnz/Tez resulted in a consistent and significant rescue of CFTR activity, overcoming the block previously observed with ETI. Of note, we report a patient treated with VTD who experienced a partial improvement in pulmonary function (FEV1 +220 mL) and exercise tolerance and a decrease of sweat Chloride concentration from 100 to 87 mmol/L. In heterologous expression systems, Vnz/Tez, but not Elx/Tez, successfully restored the processing of the L467F-F508del mutant, promoting the formation of the mature, complex-glycosylated CFTR form. Our findings demonstrate that the Vanzacaftor/Tezacaftor combination possesses superior corrective potency capable of rescuing the severe trafficking defect of the L467F-F508del complex allele. This study identifies a promising therapeutic solution for patients currently orphaned by standard-of-care modulators and highlights the utility of integrating ex vivo screening with clinical monitoring in defining precision medicine strategies.

Colonic epithelial regeneration shapes susceptibility to

bioRxiv : the preprint server for biology

Abstract: Clostridioides difficile infection (CDI) susceptibility and severity are strongly associated with preexisting colonic inflammation. However, chronic inflammatory conditions such as cystic fibrosis rarely progress to symptomatic CDI despite high rates of C. difficile colonization, suggesting that inflammation alone is insufficient to explain disease vulnerability. Notably, populations relatively protected from symptomatic CDI exhibit impaired regenerative capacity within the colon epithelium. Here, we used single cell RNA sequencing of human colonoid monolayers to map markers of CDI susceptibility and severity to cell populations associated with inflammation and epithelial repair. We identified an inducible microfold-like (M-like) population that is largely absent from the healthy colon but emerges during inflammation and regeneration. These cells were enriched for markers of severe CDI, C. difficile toxin interaction genes, and elevated CCL20 and CFTR expression. Spatial imaging localized CCL20-producing cells to wound-like gaps in mock and CDI-treated colonoids, identifying a repair-associated niche active independent of infection. Following exposure to C. difficile , wound-healing transcription within the M-like lineage declined while tuft-like populations expanded and upregulated genes associated with immune cell recruitment. These findings demonstrate that epithelial regeneration shapes host CDI vulnerability. Clostridioides difficile infection can lead to severe illness and death in vulnerable populations despite available treatments. Clinical signs of inflammation during active Clostridioides difficile infection are strongly associated with disease outcome, yet these responses primarily reflect tissue damage already underway, limiting opportunities to prevent progression. In contrast, conditions linked to severe disease, including inflammatory bowel disease and antibiotic exposure, are associated with colonic inflammation before infection or at the time of diagnosis, highlighting an opportunity for earlier identification of high-risk individuals. Using human colonoid single cell transcriptomics and spatial imaging, we identified a microfold-like cell population enriched for inflammatory mediators and Clostridioides difficile toxin interaction genes linked to severe disease. This population was active even in the absence of infection, suggesting that repair-associated populations within the inflamed colon may help identify susceptibility to severe CDI before clinical progression occurs.

Red blood cell deformability as a mechanobiological marker of CFTR dysfunction in cystic fibrosis.

Abstract: Cystic fibrosis (CF) is a genetic disorder caused by mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR), a chloride channel that controls salt and fluid transport across membranes. While CFTR is mainly studied in epithelial tissues, it is also detectable in red blood cells (RBCs), with a reduced expression in individuals with CF. However, the impact of this reduction on RBC deformability remains unexplored. Here, we investigated RBC deformability in CF using osmotic gradient ektacytometry. We examined 70 subjects with CF or CFTR-related disorders and compared them with 46 healthy control subjects. Our findings identify significant and reproducible alterations in RBC deformability associated with CFTR dysfunction, partially restored in subjects receiving highly effective CFTR modulators. These results support RBC deformability as a functional phenotype of CFTR dysfunction with prognostic potential, encouraging further investigations into the role of RBC membrane channels in cellular mechanics.


Involved in oxygen transport from the lung to the various peripheral tissues LVV-hemorphin-7 potentiates the activity of bradykinin, causing a decrease in blood pressure Functions as an endogenous inhibitor of enkephalin-degrading enzymes such as DPP3, and as a selective antagonist of the P2RX3 receptor which is involved in pain signaling, these properties implicate it as a regulator of pain and inflammation

Gut microbiota remodeling in

Abstract: Gastrointestinal symptoms frequently accompany anemia caused by HBB mutations, such as β-thalassemia; however, the mechanisms linking disordered hemoglobin biology to intestinal dysfunction remain incompletely understood. In this study, HBB-mutant cynomolgus monkeys were generated and analyzed together with wild-type (WT) controls through integrated metabolomic and metagenomic profiling. HBB mutation was associated with a marked shift in gut microbial ecology, characterized by reduced microbial diversity and altered abundances of Lactobacillus and Bacteroides. Metabolic profiling revealed broad perturbation of amino acid, lipid, energy, and immune-related metabolic pathways, with 3-oxooctadecanoic acid (HMDB0254633) emerging as a discriminative metabolite between WT and HBB-mutant animals. Multiomics integration indicated that HBB mutation reshaped microbiota-metabolite interactions and may thereby affect host metabolism and immune responses. To examine the functional relevance of this metabolite, 3-oxooctadecanoic acid was administered to C57BL/6 mice with castor oil-induced diarrhea. High-dose treatment alleviated diarrhea severity, improved stool parameters, limited body weight loss, and partially restored gut microbial composition. These findings provide non-human primate evidence that β-thalassemia-associated HBB mutation disrupts intestinal microbiota homeostasis and metabolic output, identifying 3-oxooctadecanoic acid as a candidate biomarker and potential regulator of gastrointestinal dysfunction. This study provides a valuable framework for understanding how host genetic variation contributes to gut microbiome remodeling and gastrointestinal manifestations in β-thalassemia. 由 HBB基因突变（如β-地中海贫血）导致贫血的患者常出现胃肠道症状，但其内在机制尚未完全阐明。该研究通过基因编辑技术构建 HBB突变型食蟹猴，结合代谢组学与宏基因组学分析，将其肠道菌群特征与野生型对照组进行比较。结果显示：突变型与野生型猴的代谢物谱存在显著差异，尤其体现在氨基酸和脂质代谢通路，并发现关键区分代谢物HMDB0254633；宏基因组分析表明两组间乳酸杆菌属和拟杆菌属丰度存在显著差异，且 HBB突变型微生物多样性较低；进一步功能分析提示基因缺陷显著改变了氨基酸代谢、能量代谢等关键通路。这些整合性发现表明 HBB突变可能通过调控肠道菌群与代谢物的相互作用，影响宿主代谢和免疫应答。此外，我们探索了3-氧代十八烷酸对蓖麻油诱导腹泻C57BL/6小鼠肠道菌群的影响，通过评估稀便率、腹泻指数和体重变化等指标，发现高剂量干预组（3_AOH）能缓解腹泻症状并改善肠道菌群组成。该研究首次在非人灵长类模型中证实β-地中海贫血可通过破坏肠道菌群稳态影响胃肠健康，并确定3-氧代十八烷酸可作为野生型与 HBB突变型细胞的共同生物标志物，这为理解β-地中海贫血症状的潜在机制提供了重要参考，同时揭示了宿主基因变异对肠道微生态调控的影响。.

Comparative in silico analysis of hemoglobin subunits HBB, HbS (p.Glu7Val), and HBA: Sequence-structure insights into sickle cell anemia.

Abstract: Sickle cell anemia is caused by a single missense mutation in the human beta globin gene (HBB) that replaced glutamic acid with valine at position 7(p.Glu7Val), producing sickle hemoglobin (HbS) and promoting polymer formation under deoxygenated conditions. In the present in silico study, genomic and protein sequences of HBB (normal beta globin), HbS variant beta globin (HbS) and hemoglobin alpha globin (HBA) were retrieved from NCBI in FASTA format and analyzed comparatively. physicochemical properties were computed using ExPASY protparam, secondary structure features were predicted using PSIPRED, and three-dimensional /quaternary structural modeling was performed using SWISS-MODEL with template selection from PDB. The ProtParam analysis display that the p.Glu7Val substitution in HBBs reduced the number of acidic residues (Asp+Glu) and shifted the theoretical PI upward(HBB:6.740, HBBs:7.131) accompanied by a∼30 Da decrease in molecular weight and a modest increase in hydrophobicity related indices (aliphatic index and GRAVY). PSIPRED predicted predominantly alpha helical globin folds for all subunits, with only minor differences between HBB and HbS. Structural inspection of the SWISS-MODEL assemblies localized Val 7 at the Beta chain N-terminus and consistent with the classical mechanism whereby this hydrophobic substitution creates a surface stick region that can engage hydrophobic patches on neighboring deoxy Hb molecules, providing structural context consistent with HbS polymerization and downstream erythrocyte sickling. Overall, this computational workflow provides a clear sequence to structure interpretation of the HbS mutation and highlights measurable physicochemical shifts associated with SCA.

The red blood cell proteome and interactome identify a Band 3-BLVRB axis regulating hypoxic metabolic adaptation.

Abstract: Red blood cells (RBCs) are transcriptionally silent yet dynamically remodel metabolism in response to oxygen tension. Using ultra-pure human RBCs, we generated the deepest contamination-free proteome to date (3,775 proteins) and mapped the oxygen-dependent interactome. These datasets reveal an oxygen-responsive metabolon centered on the Band 3 (SLC4A1) N-terminus. We identify biliverdin reductase B (BLVRB) as a previously unrecognized Band 3 interactor that dissociates under hypoxia, coincident with increased Band 3-deoxyhemoglobin contacts. This reversible assembly functions as an oxygen-sensitive switch coordinating redox and glycolytic remodeling. Humanized mice lacking Band 3 N-terminal segments exhibit impaired oxygen-dependent regulation of BLVRB binding to band 3, impaired hypoxic activation of glycolysis, reduced 2,3-bisphosphoglycerate synthesis, and diminished exercise tolerance, demonstrating physiological relevance. Population-scale cis-pQTLs for SLC4A1 and BLVRB suggest functions beyond canonical heme catabolism. Mechanistically, biochemical analyses in vitro suggest that hemoglobin β (HBB), Band 3, and BLVRB can undergo S-nitrosation and may participate in trans-nitrosation reactions with the glycolytic enzyme GAPDH, whose modification at C152 inhibits enzymatic activity in vitro. Collectively, these findings define a Band 3-BLVRB axis that integrates oxygen-dependent protein interactions with thiol-based redox chemistry, providing a framework for understanding how an anucleate cell achieves metabolic adaptability through reversible protein-protein interactions and post-translational modification. These findings suggest that perturbation of the Band 3-BLVRB axis may influence oxygen delivery and metabolic flexibility during hypoxic stress, with potential relevance to high-altitude adaptation, exercise physiology, and cardiopulmonary disease.

A Dual-Viral Delivery Platform Enables Efficient Site-Specific Integration of Therapeutic-Length Genes in Human Primary Stem Cells.

Abstract: Site-specific integration of large genes in human primary stem cells remains a significant challenge in gene therapy, particularly for treating multiallelic diseases. Gene editing efficiency in primary stem cells is heavily influenced by the delivery strategy, which often faces issues with programmability, efficiency, and specificity. Here, we developed a dual-viral delivery system, targeted integration via virus-like particles and integrase-deficient lentivirus (TIVID). This system combines virus-like Cas9 edit particles for delivering Cas9/sgRNA ribonucleoprotein complexes and integrase-deficient lentiviral vectors for delivering HDR donor templates. The TIVID system achieves a knock-in efficiency of 65% ± 5% in human induced pluripotent stem cells (iPSCs). In erythroid progenitor HUDEP2 cells, TIVID mediates precise integration of a 7.1 kb HBB-GFP cassette (from cut site to cut site) at the AAVS1 locus with 20% efficiency and stable expression. Crucially, we demonstrate that TIVID overcomes stringent packaging constraints to deliver an approximately 6 kb full-length HBB therapeutic cassette into primary human CD34+ hematopoietic stem and progenitor cells. This platform achieved 5-10% targeted integration efficiency and preserved robust lineage-specific differentiation capacity, demonstrating its potential for treating β-thalassemia and other multiallelic disorders. In head-to-head comparisons, TIVID outperformed lentivirus-derived nanoparticles (∼50% vs. <10% at AAVS1 in K562 with M3814) and plasmid-based eePASSIGE in iPSCs (∼20% vs. ∼1.5%). Compared with traditional electroporation delivery, TIVID offers lower early cytotoxicity, promotes predominantly mono-allelic integration, and exhibits enhanced compatibility with primary stem cells. By decoupling nuclease and donor delivery, TIVID circumvents the payload constraints of single-vector systems and the toxicity of physical transfection, providing a robust ex vivo engineering platform for complex gene replacement therapies.

Meta-analysis across six global biobanks identifies recessive coding associations with complex traits and diseases.

Abstract: Rare bi-allelic variation is a major contributor to human disease risk, yet its effects are difficult to study at scale in population cohorts owing to the limited number of individuals with putatively deleterious bi-allelic genotypes and the challenges of accurately phasing low-frequency variants. Here, we present recessive, gene-based analyses of rare and low-frequency variants in up to 948,690 exome- or whole-genome-sequenced individuals across six biobanks with linked electronic health records. Through statistical phasing, we inferred putatively damaging compound-heterozygous genotypes, increasing the number of bi-allelic damaging genotypes by 19%. Restricting to predicted loss-of-function (pLoF) variants, we identified 5,563 genes harboring bi-allelic genotypes, a 19.8% increase in putative knockouts. We then considered all low-frequency variants (minor allele frequency [MAF] <5%) and performed gene-based recessive association testing using putatively damaging bi-allelic genotypes, identifying 58 significant associations (false discovery rate [FDR] ≤1% or prec≤7.5 × 10-7) after meta-analysis and Cauchy combination of nonsynonymous annotations. Comparing recessive and additive models, we found 17 instances where recessive effects were more pronounced, including several previously unreported associations, such as HBB with heart failure (prec = 2.6 × 10-14; padd = 0.98), LECT2 with height (prec = 3.7 × 10-14; padd = 4.1 × 10-10), and ENSG00000267561 with height (prec = 2.9 × 10-9; padd = 0.37). This study demonstrates the potential of federated approaches to study the effects of rare bi-allelic variation.


Myosins are actin-based motor molecules with ATPase activity essential for muscle contraction. Forms regular bipolar thick filaments that, together with actin thin filaments, constitute the fundamental contractile unit of skeletal and cardiac muscle

Beta-Adrenergic Stimulation and

Abstract: Hypertrophic cardiomyopathy (HCM) is the most prevalent genetic heart disorder, characterized by significant phenotypic variability even among individuals with identical MYH7 mutations. This study aims to elucidate factors contributing to this variability and identify drivers of phenotype penetrance. We compared the baseline phenotypes of a highly penetrant MYH7 H251N mutation and the variably penetrant MYH7 G256E mutation and investigated the impact of adding beta-adrenergic stimulation and homozygosity on disease phenotype penetrance using cardiomyocytes from an isogenic line of human induced pluripotent stem cells (hiPSC-CMs). Isogenic hiPSCs with MYH7 H251N and MYH7 G256E mutations were generated using CRISPR/Cas9 technology and differentiated into cardiomyocytes (CMs). Single-cell RNA sequencing (scRNAseq) and functional analysis of contractile function revealed consistent HCM phenotype presentation in H251N CMs, whereas G256E CMs exhibited a subtle and more variable phenotype. Beta-adrenergic stimulation induced a distinct metabolic stress response in G256E CMs, characterized by impaired mitochondrial ATP upregulation. Increasing mutant gene dosage from hetero- to homozygosity led to consistent increase in hypertrophic and structural gene expression changes in G256E CMs at RNA and protein levels. These changes were distinct from the changes observed with stress response. Importantly, homozygous G256E CMs exhibited a hypercontractile functional and disorganized structural phenotype. Across multiple experimental conditions, we identified consistent increase in cardiomyocyte specific transcriptomic markers such as NPPB , APOE , PDLIM3 and ANKRD1 . Our study highlights the use of a variably penetrant MYH7 mutation to investigate factors that influence HCM phenotype penetrance. Specifically, we found that mutant gene dosage and beta-adrenergic stimulation induce distinct HCM disease phenotypes, providing novel insights into mechanisms that may contribute to variable disease expression in HCM. HCM is characterized by significant phenotypic variability, complicating both diagnosis and clinical management. This study explores the factors driving HCM phenotype penetrance using isogenic hiPSC-CMs with MYH7 mutations. We demonstrate that beta-adrenergic stimulation and increased mutant gene dosage significantly impact HCM disease penetrance. Beta-adrenergic stimulation triggers metabolic stress responses, while increased gene dosage leads to a hypercontractile and structurally disorganized phenotype. These findings provide insight into how specific modifiers can shape disease-associated phenotypes in HCM model systems.

Sex and Age Specific Genetic Risk Across the Dilated and Arrhythmogenic Cardiomyopathy Spectrum: Insights From the SHaRe Registry.

Journal of the American College of Cardiology

Abstract: Dilated cardiomyopathy (DCM) and arrhythmogenic cardiomyopathy (ACM) are progressive cardiac muscle disorders with phenotypic and genetic overlap. Although a male predominance is noted in DCM/ACM, it remains unclear whether this extends to specific genetic subtypes or reflects variation in disease stage and whether sex influences age-dependent disease onset across pediatric and adult groups. The aim of this study was to define sex-based differences in genetic architecture and age at diagnosis of DCM/ACM across pediatric and adult populations. Genetically tested adult and pediatric DCM/ACM patients and asymptomatic genotype-positive relatives enrolled in the multicenter SHaRe (Sarcomeric Human Cardiomyopathy Registry) were analyzed. Sex distribution across 27 DCM- and ACM-associated genes was evaluated using logistic regression. Age at diagnosis was compared across sex and genes using Kaplan-Meier cumulative incidence estimates. Among 3,410 patients, a 61% male predominance was present across subgroups of genotype positive, genotype negative, and variants of uncertain significance (P = 0.008), with significant gene-specific variation. TTN truncating variants (TTNtv) were less common in females (OR: 0.42 [95% CI: 0.33-0.54]; P < 0.01), while DSP (OR: 3.3 [95% CI: 2.35-4.78]; P < 0.01) and grouped non-TTN sarcomeric variants (ACTC1, TNNT2, MYH7, TNNC1, TNNI3, and TPM1) were more common (OR: 1.68 [95% CI: 1.15-2.47]; P < 0.001) in females compared with males with DCM/ACM. Age at diagnosis was comparable between sexes, except in TTNtv carriers, among whom males exhibited earlier disease onset compared with females (median age 45 years [Q1-Q3: 33-55 years] vs 51 years [Q1-Q3: 38-60 years]; P = 0.003). Pediatric-onset (diagnosis at <18 years) cases (n = 174) also demonstrated a male predominance (60% male) but had distinct genetic characteristics, with non-TTN sarcomeric and PKP2 variants being more prevalent compared with adult-onset disease (non-TTN sarcomeric OR: 5.5 [95% CI: 3.3-8.9; P < 0.01]; PKP2 OR: 2.8 [95% CI: 1.1-5.2; P < 0.05]) and a bimodal age at onset peaking in infancy and adolescence. Gene-specific sex differences influence disease prevalence and age at onset in DCM/ACM. TTNtv are more common with earlier onset in males, whereas DSP and non-TTN sarcomeric variants predominate in females. Pediatric-onset DCM/ACM is genetically distinct and caused predominantly by non-TTN sarcomeric variants, especially during infancy. These findings support age- and sex-informed surveillance strategies and prioritize future research into the mechanisms of observed sex-based differences.

Uncovering the gene variants in a global cohort of patients with unexplained increased left ventricular wall thickness using next-generation sequencing.

Abstract: Genetic analysis using massive parallel sequencing is crucial for the accurate and early diagnosis of hereditary hypertrophic cardiomyopathies and their phenocopies, especially transthyretin cardiac amyloidosis (ATTR-CA) and Fabry disease (FD). This study extends the cardio next-generation sequencing (NGS) pilot study by investigating the detection rate of gene variants causing increased left ventricular wall thickness (LVWT) using an expanded 19-gene NGS panel in a larger global cohort. This study included 2068 patients with unexplained increased LVWT enrolled at cardiological clinics across 22 countries/regions between 2020 and 2022. The NGS panel comprised 19 genes associated with hypertrophic cardiomyopathy (HCM) and its phenocopies. Sequencing was performed using the Illumina NextSeq 500 and NovaSeq 6000 systems, with variant interpretation performed according to the American College of Medical Genetics and Genomics guidelines. Novel variants were analyzed using the Human Gene Mutation Database (HGMD®), Franklin, and VarSome. Among the 2068 patients, 453 patients were positive for pathogenic/likely pathogenic variants (21.9%). The diagnostic yield for HCM was 18.4%, while that of HCM phenocopies was 3.5%, including ATTR-CA (1.5%), and FD (0.9%). In patients with a positive test (HCM or HCM phenocopies), the most prevalent HCM-related variants were MYBPC3 and MYH7 (36.4% and 34.4% of all positive samples, respectively), whereas TTR (7.1%) and GLA (4.0%) were the most common phenocopy variants. Other classical phenocopies, Noonan syndrome, Danon disease, and PRKAG2, comprised another 2.0%, 0.9%, and 0.7% of the cohort, respectively. The mean ages for patients with HCM sarcomeric gene variants, HCM phenocopy variants, FD, and ATTR-CA were 45.1 ± 17.6, 50.9 ± 23.7, 51.1 ± 19.4, and 64.6 ± 19.0 years, respectively. This study demonstrates the need to include GLA and TTR in NGS panels for patients with increased unexplained LVWT. NGS effectively identifies phenocopies often missed by imaging. Using a large, diverse cohort, this study reveals the prevalence of FD and ATTR-CA in patients with unexplained increased LVWT, reinforcing the importance of NGS for early diagnosis and targeted therapy. The online version contains supplementary material available at 10.1186/s12872-026-05834-5.

Generation of two induced pluripotent stem cell lines from female patients harboring MYH7 mutations with hypertrophic cardiomyopathy.

Abstract: Hypertrophic cardiomyopathy (HCM) is a cardiac disorder marked by left ventricular thickening and impaired diastolic function, often caused by truncating variants in MYH7 gene. In this work, we generated two human iPSC lines from female HCM patients, each carrying a distinct heterozygous MYH7 mutation (c.611G > T and c.505A > G). Both lines displayed a normal karyotype, typical pluripotent stem cell morphology, strong expression of key pluripotency markers, and retained the capacity to differentiate into cell types representing all three germ layers. These patient-specific female iPSC lines provide a valuable platform to explore inter-patient variability and the mechanistic diversity underlying MYH7-associated cardiomyopathies.

FGF12 Alleviates Cardiac Hypertrophy by Inhibiting Phosphorylation of CaM/CaMKII/CREB1 Axis.

Circulation. Genomic and precision medicine

Abstract: Hypertrophic cardiomyopathy (HCM) arises from genetic mutations in sarcomere proteins, resulting in major structural abnormalities and limited treatment options. Patients with HCM had reduced expression of the FGF12 (fibroblast growth factor 12), but its precise functional role remains unclear. To explore FGF12's function and interactions, we utilized clustered regularly interspaced short palindromic repeats-Cas9 technology in cardiomyocytes derived from human induced pluripotent stem cells-induced cardiomyocytes, as well as in other cell lines and mouse models (MYH7R403Q/+, MYBPC3c790GtoA/c790GtoA, and transverse aortic constriction models). We transfected HCM or mice model with FGF12-coding sequence and FGF12-ΔNLS plasmids or adeno-associated virus 9 vectors to reduce myocardial hypertrophy. As hypertrophy progressed, we used cleavage under targets and tagmentation) sequencing and AlphaFold3 on myocardial tissues from patients and induced pluripotent stem cells-induced cardiomyocytes. To predict mitochondrial function in cardiomyocytes, we measured mitochondrial Ca2+ concentrations and reactive oxygen species content. First, we observed a decrease in FGF12 expression and a difference in its subcellular localization in patients with HCM compared with healthy volunteers. In hypertrophic mouse models, injecting adeno-associated virus 9 reduced myocardial hypertrophy. FGF12 binds to calmodulin and inhibits its phosphorylation. This interaction also suppresses the expression and phosphorylation of downstream proteins, including CaMKII, ERK1/2, CREB1, and MCU. The nuclear-localization FGF12 binds to the promoter region of CREB1. FGF12 inhibits the expression of the CREB1-MCU axis expression, leading to reductions in both mitochondrial Ca2+ concentration and mitochondrial reactive oxygen species. This study reveals a pathological mechanism associated with HCM linked to FGF12. FGF12, located outside the nucleus, suppresses the expression of metabolism-related genes by reducing the phosphorylation levels within the calmodulin-ERK1/2-CREB1-MCU axis. In contrast, the nuclear localization of FGF12 facilitates its binding to the promoter regions of CREB1, inhibiting CREB1 expression. This dual action maintains cardiomyocyte function and mitochondrial homeostasis. Our findings position FGF12 as a promising therapeutic target for HCM.


Potassium voltage-gated channel subfamily KQT member 1

Pore-forming subunit of the voltage-gated potassium (Kv) channel involved in the regulation of cardiomyocyte excitability and important in normal development and functions of myocardium, inner ear, stomach and colon (PubMed:10646604, PubMed:25441029). Associates with KCNE beta subunits that modulates current kinetics (PubMed:10646604, PubMed:11101505, PubMed:19687231, PubMed:8900283, PubMed:9108097, PubMed:9312006). Induces a voltage-dependent current by rapidly activating and slowly deactivating potassium-selective outward current (PubMed:10646604, PubMed:11101505, PubMed:25441029, PubMed:8900283, PubMed:9108097, PubMed:9312006). Also promotes a delayed voltage activated potassium current showing outward rectification characteristic (By similarity). During beta-adrenergic receptor stimulation, participates in cardiac repolarization by associating with KCNE1 to form the I(Ks) cardiac potassium current that increases the amplitude and slows down the activation kinetics of outward potassium current I(Ks) (By similarity) (PubMed:10646604, PubMed:11101505, PubMed:8900283, PubMed:9108097, PubMed:9312006). Muscarinic agonist oxotremorine-M strongly suppresses KCNQ1/KCNE1 current (PubMed:10713961). When associated with KCNE3, forms the potassium channel that is important for cyclic AMP-stimulated intestinal secretion of chloride ions (PubMed:10646604). This interaction with KCNE3 is reduced by 17beta-estradiol, resulting in the reduction of currents (By similarity). During conditions of increased substrate load, maintains the driving force for proximal tubular and intestinal sodium ions absorption, gastric acid secretion, and cAMP-induced jejunal chloride ions secretion (By similarity). Allows the provision of potassium ions to the luminal membrane of the secretory canaliculus in the resting state as well as during stimulated acid secretion (By similarity). When associated with KCNE2, forms a heterooligomer complex leading to currents with an apparently instantaneous activation, a rapid deactivation process and a linear current-voltage relationship and decreases the amplitude of the outward current (PubMed:11101505). When associated with KCNE4, inhibits voltage-gated potassium channel activity (PubMed:19687231). When associated with KCNE5, this complex only conducts current upon strong and continued depolarization (PubMed:12324418). Also forms a heterotetramer with KCNQ5; has a voltage-gated potassium channel activity (PubMed:24855057). Binds with phosphatidylinositol 4,5-bisphosphate (PubMed:25037568). KCNQ1-KCNE2 channel associates with Na(+)-coupled myo-inositol symporter in the apical membrane of choroid plexus epithelium and regulates the myo-inositol gradient between blood and cerebrospinal fluid with an impact on neuron excitability (By similarity) Non-functional alone but modulatory when coexpressed with the full-length isoform 1

Wavelet Decomposition-Based Genomic Analysis of the Human Electrocardiogram.

medRxiv : the preprint server for health sciences

Abstract: The electrocardiogram (ECG) encodes the electrical activity of the heart across multiple timescales, yet standard clinical analysis collapses this rich signal into a handful of scalar measurements that discard most of the waveform's structure. Whether the frequency signals lost in this reduction carry heritable biological information relevant to cardiovascular disease risk remains unclear. Here we decompose resting 12-lead ECGs from 47,052 White British UK Biobank participants into 84 frequency-specific energy features using Daubechies-6 wavelet analysis across 12 leads and 7 decomposition levels, and perform independent genome-wide association analyses on each feature. We identify 67 independent loci and refine these to 101 high-confidence causal variants (posterior inclusion probability > 0.80) through Bayesian fine-mapping; associated loci converge on genes governing cardiac conduction and myocardial integrity, including SCN5A, TTN, KCNQ1, and DSP, alongside less-characterized cardiomyopathy candidates. SNP-based heritability estimates range from 0.03 to 0.26, with the strongest signals in mid-frequency bands (D6-D4, ~4-32 Hz) of Lead I and aVR, and strong inter-lead genetic correlations indicate a coordinated genetic architecture underlying the waveform. Integrating these features with FinnGen R12 cardiovascular phenotypes reveals genetic correlations reaching 0.56 with heart failure, driven predominantly by energy in the highest-frequency band (D1, 125-250 Hz), a spectral range routinely filtered from clinical ECGs and previously regarded as acquisition noise. These results reframe the electrocardiogram as a multi-frequency genetic phenotype, expand the set of cardiac loci discoverable from ECG data, and implicate high-frequency cardiac electrical activity as an underexplored dimension of cardiovascular disease risk.

Discovery of Small-Molecule Inhibitors of the KCNQ1/Kv7.1 Potassium Channel with Virtual Screening and Functional Validation in Electrophysiological Assays and KCNQ1-Knockout Neural Stem Cells.

Abstract: Voltage-gated potassium channel KCNQ1 (Kv7.1) plays a critical role in electrical excitability in the heart, gut, and brain. Together with the auxiliary subunit KCNE1, KCNQ1 generates a slow delayed rectifier current (IKs) that is essential for cardiac repolarization. Mutations and dysregulation of this channel are found in channelopathies leading to sudden death, long-QT syndrome, atrial fibrillation, epilepsy, deafness, diabetes, and neuropsychiatric disorders. Although KCNQ1 and related potassium channels are promising therapeutic targets, there are few potent, selective, and therapeutically safe inhibitors and activators available for these proteins. A virtual screening of 36,374 compounds was conducted against KCNQ1, followed by in silico analyses that identified eight potential ligand candidates for experimental evaluation using human KCNQ1 coexpressed with KCNE1 in Xenopus laevis oocytes. Electrophysiological recordings showed that the benzodiazepine-based ligand Zinc13732787 was a potent inhibitor of the channel complex, without affecting KCNQ2/KCNQ3. Based on virtual screening and molecular docking, the 1-(3-chlorophenyl)-urea substituent on the benzodiazepine core is important for selective inhibition of KCNQ1/KCNE1, as further supported by structure-activity relationship and stereochemical exploration of Zinc13732787. Furthermore, low concentrations of Zinc13732787 reduced neurite outgrowth in human neuronal stem cells (NSCs), mirroring the phenotype observed in homozygous KCNQ1-knockout cells. Importantly, Zinc13732787 did not affect NSC proliferation, nor did it induce cytotoxicity. In homozygous KCNQ1-knockout NSCs, compound Zinc13732787 had no effect on neurite outgrowth, indicating high target specificity. These findings suggest that this compound is a valuable tool for investigating the physiological and pathological roles of KCNQ1 across various tissues. Additionally, it could be used as a precursor for novel antiarrhythmic agents as well as for epilepsy and neuropsychiatric conditions.

Machine learning-guided risk stratification for Long QT Syndrome genetic variants with hiPSC-derived cardiomyocytes.

Abstract: Long QT syndrome (LQTS) is a life-threatening genetic disorder characterized by prolonged QT intervals on electrocardiograms. Congenital forms are mostly associated with variants in the KCNQ1 and KCNH2 genes. Among pathogenic or likely pathogenic (P/LP) variants, some are associated with a significantly higher incidence of cardiac events compared to others. While therapies have significantly reduced mortality, some patients are unresponsive or intolerant to therapy, perpetuating their arrhythmic risk, including sudden cardiac death. Current approaches for risk stratification are insufficient, highlighting the critical need for more accurate identification and management of patients carrying high risk genetic variants.Here, we aimed to develop a refined risk stratification model for P/LP variants by applying machine learning classification to electrophysiological data measured in patient-specific human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). Ten patient-specific hiPSC lines, each carrying one of six pathogenic or likely pathogenic (P/LP) variants in the KCNQ1 or KCNH2 genes, along with two healthy control hiPSC lines, were differentiated into cardiomyocytes (hiPSC-CMs). Electrophysiological responses from multielectrode array recordings at baseline and after application of selective ion channel blockers or pro-arrhythmic compounds were used to train a machine learning model to classify variant-specific risk levels based on in vitro electrophysiological readouts. An independent validation cohort of two additional KCNH2 hiPSC lines was used to test the model's performance in predicting single-variant risk.Our findings revealed a correlation between variant risk level, hiPSC-CM electrophysiological profiles, and drug responses. The machine learning classifier, trained on multielectrode array recordings, achieved 89% accuracy in classification of P/LP genetic variants according to the associated risk levels. This study demonstrates that integrating hiPSC-CM electrophysiological profiling with machine learning provides a robust method for granular variant-specific risk stratification of LQTS patients.

Role of natural inter-individual variability in the different penetrance of congenital long QT syndromes (LQTS) types 1 and 2: an in silico approach.

Abstract: Congenital Long QT Syndrome types 1 and 2 (LQT1 and LQT2) are caused bymutations in the KCNQ1 and KCNH2 genes, responsible for the IKs and IKr currents, respectively. However, the penetrance of these mutations is highly variable, since some carriers remain asymptomatic, while others exhibit severe clinical manifestations. To elucidate how physiological variability in other cardiac ionic currents may influence the arrhythmic phenotype, human ventricular action potentials were simulated in silico using the O'Hara-Rudy dynamic model implemented in the Virtual Assay software. Conductances of nine key ionic currents were randomly modified within physiologically plausible ranges and the resulting population of models was validated under stress conditions. LQT1 and LQT2 cohorts were generated by reducing IKs by 80% and IKr by 60%, respectively. These cohorts were stratified into four risk categories based on action potential duration (APD) under different conditions and the occurrence of arrhythmic events. LQT1 models demonstrated impaired adaptation to adrenergic stimulation, whereas LQT2 models showed marked APD prolongation at rest. Risk stratification revealed a higher incidence of arrhythmic events in LQT2 (7.6%) compared to LQT1 (0.55%). Regression analyses identified IKr and IK1 as protective currents, while INaL and ICaL were major contributors to APD prolongation in both types. Simulated blockade of L-type Ca²⁺ channels effectively shortened APD and reduced the proportion of high-risk models. The natural variability in ionic current profiles contributes to the phenotypic expression of LQTS and support the potential use of calcium channel blockers as therapeutic alternatives in patients unresponsive to β-blockers.

Human iPSC-Based Modeling Identifies Epigenetic Regulation at the KCNQ1 Locus During Early Islet Development That Contributes to Lower β-Cell Mass.

Abstract: The strongest type 2 diabetes signal in Indigenous Americans from Arizona is in intron 15 of KCNQ1. We previously identified a functional region in this intron that contained four type 2 diabetes-associated single nucleotide polymorphisms (SNPs) (rs2299620, rs2237896, rs2237897, and rs74046911) and demonstrated functionality of this fragment using Indigenous American induced pluripotent stem cell (iPSC)-derived pancreatic islets (SC-islets). In the current study, we used isogenic iPSCs with targeted edits at these four SNPs, and three additional SNPs (rs2237895, rs60808706, and rs234864), to generate SC-islets and study the effect of these variants during different developmental stages. We identify an 11% reduction in stem cell-derived β-cells (SC-β-cells) in SC-islets with the risk alleles, suggesting an effect of these variants on β-cell mass. We further show premature endocrine commitment in cells with the risk allele and lower rate of β-cell commitment during the endocrine progenitor stages, likely due to differences in H19 and INS gene expression dynamics. We also show that the differential expression may be attributable to lower CpG methylation and higher chromatin accessibility in cells with the risk alleles. In summary, the type 2 diabetes SNPs at KCNQ1 affect SC-β-cell generation, and this effect is manifested early during development, likely via an epigenomic effect on gene regulation. We previously developed an induced pluripotent stem cell-based model to study an intronic region of KCNQ1 that represents the strongest association signal with type 2 diabetes in Indigenous Americans from Arizona. The current study builds on this model by using CRISPR/Cas9-edited isogenic cells that differ only by targeted type 2 diabetes single nucleotide polymorphisms in this intronic region. The effect of KCNQ1 type 2 diabetes single nucleotide polymorphisms on pancreatic β-cell development and the probable mechanism of this effect were previously unknown. The current study shows an effect on INS and H19 gene expression dynamics specifically during the endocrine progenitor stage of pancreatic islet development likely via an epigenomic effect on gene regulation resulting in generation of lower β-like cells. Individuals carrying KCNQ1 risk alleles for type 2 diabetes will likely benefit from therapeutics that increase pancreatic β-cell mass.


Tyrosine-protein kinase that acts as a cell-surface receptor for fibroblast growth factors and plays an essential role in the regulation of cell proliferation, differentiation and apoptosis. Plays an essential role in the regulation of chondrocyte differentiation, proliferation and apoptosis, and is required for normal skeleton development. Regulates both osteogenesis and postnatal bone mineralization by osteoblasts. Promotes apoptosis in chondrocytes, but can also promote cancer cell proliferation. Required for normal development of the inner ear. Phosphorylates PLCG1, CBL and FRS2. Ligand binding leads to the activation of several signaling cascades. Activation of PLCG1 leads to the production of the cellular signaling molecules diacylglycerol and inositol 1,4,5-trisphosphate. Phosphorylation of FRS2 triggers recruitment of GRB2, GAB1, PIK3R1 and SOS1, and mediates activation of RAS, MAPK1/ERK2, MAPK3/ERK1 and the MAP kinase signaling pathway, as well as of the AKT1 signaling pathway. Plays a role in the regulation of vitamin D metabolism. Mutations that lead to constitutive kinase activation or impair normal FGFR3 maturation, internalization and degradation lead to aberrant signaling. Over-expressed or constitutively activated FGFR3 promotes activation of PTPN11/SHP2, STAT1, STAT5A and STAT5B. Secreted isoform 3 retains its capacity to bind FGF1 and FGF2 and hence may interfere with FGF signaling

Targeting FGFR signaling overcomes therapeutic resistance and immune evasion in oncogenic PIK3CA-driven serous-like endometrial cancer.

Abstract: Serous endometrial cancer (SEC) is an aggressive subtype of endometrial cancer (EC) with poor prognosis and limited treatment options. Here, we develop a clinically relevant, immunocompetent serous-like mouse model incorporating oncogenic PIK3CA mutation, Trp53 loss, and MYC overexpression. Using this model together with human EC cell lines, patient-derived organoids (PDOs), xenografts, and patient datasets, we investigate mechanisms underlying resistance to PI3Kα-targeted therapy. Single-cell profiling reveals that FGFR1/2 upregulation associates with intrinsic resistance, whereas FGFR3 characterizes acquired resistance. Dual FGFR and PI3Kα inhibition produces superior tumor control compared with either agent alone. Mechanistically, FGFR signaling promotes immune evasion by downregulating MHC-I/HLA-mediated antigen presentation and enriching M2-type tumor-associated macrophages. FGFR inhibition reverses these changes and synergizes with anti-PD-1 therapy to enhance antitumor immune responses and establish durable immune memory. Collectively, these findings identify FGFR signaling as a key driver of therapeutic resistance and immune escape in SEC and support FGFR-targeted combination strategies.

Impact of Copy Number Alterations on Human Papillomavirus (HPV)-Induced and HPV-Independent Penile Cancers.

Laboratory investigation; a journal of technical methods and pathology

Abstract: Penile squamous cell carcinomas (SCC) develop via transforming human papillomavirus (HPV) infection or independent of HPV. The association of copy number alterations (CNA) affecting chromosome arms, amplifications or deletions of tumor suppressor/oncogenes with HPV status and somatic mutations is largely unknown. CNA in 121 penile SCC (52% HPV associated, 48% HPV independent) were assessed using shallow whole-genome sequencing and correlated with hotspot mutations in 50 cancer driver genes. CNA were common with frequent complex co-occurrences in both etiologies. Arm-level changes included gains of 3q, 8q (48% each), 1q (36%), 1p (26%), 9q (36%), and 9p (31%) and losses of 19p (48%), 8p (44%), 19q (36%), and 3p (33%). Oncogene amplifications included broad 3q alterations (43%; TP63, SOX2, and PIK3CA) and 8q alterations (40%; MYC, HEY1, and RAD21). MYC amplifications coincided with an increased fraction of genome altered indicating genomic instability (P=.00001). Homozygous deletions affected 8p (29%; WRN, NRG1), and 3p (19%, BAP1, FANCD2, VHL) and 11q22/23 (19%, ARHGEF12, BCL9L, ATM) in both etiologies. CNA affecting TP53, CDKN2A/B, CDKN1A/B, and RB1 occurred in both, HPV-induced (16%) and HPV-independent SCC (24%), while tumor suppressor gene mutations were exclusive to HPV-independent SCC. Further differences included more amplifications on 1p in HPV-induced SCC (adjusted P = .003), compared to more 8q full-arm gains (adjusted P = .00003), amplifications of oncogenes on 8q including MYC (adjusted P = .006), and homozygous deletions of 8p (adjusted P = .03) in HPV-independent SCC. EGFR amplifications dominated in HPV-independent TP53/CDKN2A wild-type SCC without dermatoses. Together with mutations in PIK3CA, HRAS, and FGFR3, CNA represent an alternate RTK/Ras/PI3K-mediated carcinogenesis pathway. Therapeutically interesting targetable CNA such as EGFR, MTAP, and ATM occurred in >50% of advanced SCC irrespective of etiology. CNA are common in penile SCC, mainly independent of HPV-status and somatic mutations and may assist in personalized treatment strategies.

Intermittent intra-articular delivery of FGF8b enhances cartilage homeostasis and attenuates osteoarthritis progression.

Abstract: Osteoarthritis (OA) is a chronic disease characterized by degeneration of articular cartilage, affecting over half a billion individuals globally. Current treatments such as non-steroidal anti-inflammatory drugs are effective in symptom relief, but lack the ability to modify OA progression. Fibroblast growth factor 8b (FGF8b) plays crucial roles in chondrogenesis and cartilage formation, suggesting its potential application in cartilage homeostasis maintenance. This study aims to investigate the effect of exogenous FGF8b on cartilage protection and OA progression, and explore the underlying mechanisms. Therapeutic effects of intra-articular FGF8b injections either once weekly or once every four weeks were evaluated in OA mouse models induced by destabilization of the medial meniscus (DMM) using histological analysis, X-ray imaging, micro-computed tomography (micro-CT), immunohistochemistry (IHC), and RNA sequencing of cartilage. Additionally, the therapeutic effects and underlying mechanisms of FGF8b on human cartilage and chondrocytes were further investigated using ex vivo OA models and in vitro assays. Once-weekly administration of FGF8b attenuated cartilage degradation while exacerbating osteophyte formation in a dose-dependent manner. Higher doses of FGF8b resulted in stronger cartilage-protective effects while increased osteophyte formation. Conversely, intermittent administration of FGF8b (once every four weeks) protected cartilage from degeneration without causing significant osteophyte formation. Mechanistically, FGF8b was found to help the maintenance of cartilage homeostasis by promoting anabolic metabolism and inhibiting catabolic metabolism in chondrocytes through activation of the FGFR3-PI3K-AKT signaling pathway. Exogenous FGF8b attenuates articular cartilage degeneration by increasing anabolism and inhibiting catabolism, thereby presenting therapeutic potential for OA treatment. In this study, we demonstrate that intermittent administration of FGF8b protects articular cartilage from degeneration by increasing anabolic metabolism and inhibiting catabolic metabolism in cartilage, making it a promising disease-modifying agent for OA. Moreover, the findings offer valuable insights into optimizing the exposure regimens of FGFs to achieve safer and more effective OA treatment.

Abstract: Serous endometrial cancer (SEC) is an aggressive subtype of endometrial cancer (EC) with poor prognosis and limited treatment options. Here, we developed a clinically relevant, immunocompetent serous-like mouse model incorporating oncogenic PIK3CA mutation, Trp53 loss, and MYC overexpression. Using this model together with human EC cell lines, patient-derived organoids (PDOs), xenografts, and patient datasets, we investigated mechanisms underlying resistance to PI3Kα-targeted therapy. Single-cell profiling reveals that FGFR1/2 upregulation associates with intrinsic resistance, whereas FGFR3 characterizes acquired resistance. Dual FGFR and PI3Kα inhibition produced superior tumor control compared with either agent alone. Mechanistically, FGFR signaling promotes immune evasion by downregulating MHC-I/HLA-mediated antigen presentation and enriching M2-type tumor-associated macrophages. FGFR inhibition reversed these changes and synergized with anti-PD-1 therapy to enhance antitumor immune responses and establish durable immune memory. Collectively, these findings identify FGFR signaling as a key driver of therapeutic resistance and immune escape in SEC and support FGFR-targeted combination strategies.

Genetic evidence that FGF21 signaling reduces problematic alcohol use and alcohol-related liver disease.

Abstract: Fibroblast growth factor 21 (FGF21) analogs are in development for metabolic dysfunction-associated steatotic liver disease (MASLD), but their impact on problematic alcohol use (PAU), alcohol use disorder, binge drinking, and alcohol-related liver disease (ALD) is unknown. We leveraged genome-wide association study data from the UK Biobank, FinnGen, Million Veterans Program, and GenomALC for PAU, alcohol use disorder, binge drinking, weekly drinks, and ALD. Our four-tier evaluation included: (1) multivariable Mendelian randomization (MR) and mediation with circulating FGF21 levels; (2) comparative MR of MASLD and ALD targets (PNPLA3, TM6SF2, HSD17B13) using liver fat and expression instruments; (3) receptor-focused MR of β-Klotho (KLB) and FGFR1/2/3 incorporating brain-region expression; and (4) a phenome-wide MR across 1,022 traits to assess safety. Genetically higher FGF21 protein levels were associated with lower PAU (β = -0.097, 95% CI -0.135 to -0.059, p = 6.13 × 10-7), fewer binge episodes, reduced drinking, and lower ALD risk (odds ratio [OR] = 0.79, 95% CI 0.638-0.987, p = 0.038). Multivariable MR and mediation attributed these effects entirely to behavioral pathways (reduced drinking, improved diet) and increased basal metabolic rate. In comparative MR, FGF21 - unlike PNPLA3, or HSD17B13 - reduced alcohol outcomes: a 1-SD rise in hepatic FGF21 expression reduced PAU (β = -0.245, 95% CI -0.409 to -0.082, p = 0.003) and ALD (OR = 0.54, 95% CI 0.417-0.697, p = 2.44×10-6) risk. Receptor analyses implicated hippocampal FGFR3 (OR = 0.909, 95% CI 0.876-0.943, p = 4.28 × 10-7) and basal ganglia KLB expression, supporting a liver-brain axis. Phenome-wide MR uncovered 28 Bonferroni-significant protective associations with higher FGF21 (e.g. gout). Hepatic FGF21 expression showed fewer on-target liabilities than HSD17B13 or PNPLA3. Human genetic evidence indicates that FGF21 analogs mitigate hazardous drinking and ALD via both behavioral and metabolic pathways. These findings distinguish FGF21 from other MASLD targets and highlight its potential for precision treatment of alcohol-related disorders. This study leverages human genetic evidence to validate FGF21 - a liver-derived hormone currently in clinical trials for fatty liver disease - as a dual-action therapeutic that both curbs harmful drinking behaviors and protects against alcohol-related liver injury, addressing a critical therapeutic gap with limited existing pharmacotherapies. The results are important for clinicians and researchers seeking precision medicine strategies for alcohol use disorder and liver disease, as well as for patients who currently face limited treatment options. By pinpointing FGF21's behavioral and metabolic pathways and demonstrating a favorable safety profile, our findings support the repurposing of FGF21 analogs in clinical trials of alcohol use disorder and alcohol-related liver disease and suggest that genetic stratification could optimize patient selection for t