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PubMed2026

Characterization and functional insights of histone deacetylases in bivalves: implications for temperature and immune response in Chlamys nobilis.

Histone deacetylases serve as pivotal epigenetic regulators that modulate chromatin remodeling and gene transcription, playing critical roles in immune defense and environmental stress responses in aquatic organisms. However, the evolutionary characteristics and functional roles of the HDAC family in bivalves remain poorly understood. In this study, genome-wide identification of the HDAC family across 30 bivalve species yielded 558 HDAC genes. Phylogenetic reconstruction categorized these genes into four conserved groups and revealed a unique, bivalve-specific SIRT8 clade. Using the noble scallop Chlamys nobilis as a representative model, expression profiling revealed distinct expression patterns among CnHDAC members. Class I and most Class III members were predominantly expressed in the gonads, while Class II members were enriched in immune-related tissues, implying their potential involvement in bivalve immunity. Upon temperature stress, CnHDAC1/2, CnHDAC11-1, CnHDAC11-2, CnSIRT2-1, CnSIRT4, CnSIRT6, and CnSIRT8-3 were significantly induced, highlighting their critical roles in temperature adaptation. Upon Vibrio exposure, CnHDAC1/2, CnHDAC8, CnSIRT4, and CnSIRT6 were upregulated, while CnHDAC4/5/7/9, CnHDAC6/10, CnSIRT2-2, CnSIRT5, CnSIRT7, and CnSIRT8-3 were downregulated, suggesting a coordinated epigenetic regulatory mechanism underlying host immune defense. In conclusion, this study systematically elucidates the evolutionary landscape of the HDAC family and underscores its potential involvement in environmental resilience and host immunity, providing a theoretical basis for the breeding of disease-resistant and stress-tolerant aquaculture bivalves.

Animals↗
PubMed2026

Nanopore-based epigenomic profiling reveals the absence of widespread CpG methylation in the African swine fever virus genome.

DNA methylation is a critical epigenetic mechanism implicated in regulating replication and transcription in DNA viruses. However, the epigenetic landscape of African swine fever virus (ASFV), a large double-stranded DNA virus infecting pigs, remains controversial. Here, we systematically profiled the DNA methylome of the first ASFV strain isolated in Hong Kong (HK_NT_202103) using Oxford Nanopore Technologies (ONT) R10.4.1 sequencing. We employed a paired design: native whole-genome sequencing (WGS) against a methylation-free whole-genome amplification (WGA) control. Using conservative thresholds, we found no evidence of 5-methylcytosine (5mC), especially typical CpG methylation, across the viral genome. Importantly, clear CpG methylation signals were successfully detected in the host genome from WGS data, confirming the functionality of the workflow to detect 5mC at CG sites. While widespread 5mC seems absent, a small number of putative N6-methyladenine (6mA) loci were identified. A specific 6mA candidate exhibited raw ionic current disruptions and gene-level intersection with another ASFV isolate (CAS19-01/2019), although it lacked single-base consensus across different methylation callers or between the two isolates. Although our biological findings are restricted to a single isolate under specific experimental conditions, this study introduces a novel, highly rigorous ONT framework for viral epigenomics research. Furthermore, the absence of ASFV CpG methylation indicates that host CpG-depletion remains a viable strategy for viral metagenomic enrichment. Ultimately, our work offers a critical methodological baseline for ASFV surveillance and highlights the necessity of targeted experimental validation for rare viral modifications.

African Swine Fever Virus↗
PubMed2026

Pharmacogenomics of antipsychotic-induced weight gain: A systematic review.

BACKGROUND: Antipsychotic-induced weight gain (AIWG) is a major clinical concern, affecting approximately 30% of patients. Clinical predictors explain only part of AIWG risk. Genetic and molecular variations are hypothesized to contribute to susceptibility. The purpose of this review is to summarize recent results to identify replicated and novel findings. STUDY DESIGN: Applying PRISMA guidelines, we searched MEDLINE, Embase, and PsycINFO (May 2018-May 2026) for studies on genetic and molecular associations with AIWG, extending our prior review. Reviews, editorials, and conference abstracts were excluded. We extracted study characteristics (design, diagnosis, antipsychotic exposure, sample size, ancestry, genetic variants, and AIWG outcomes) (e.g., ≥7% weight gain, BMI change). RESULTS: Fifty-three studies met inclusion criteria. In candidate gene studies, the most consistently replicated genes associated with AIWG were observed for DRD2, HTR2C, and MC4R. Multiple novel associations were identified by genome-wide association studies (GWAS) (e.g., MAP2K1, ZDBF2, PEPD), polygenic risk scores (PRS) (e.g., body mass index PRS), gene expression (e.g., CYP3A4, EP300), and epigenetic analyses (e.g., cg12034943 at CRTC1). CONCLUSIONS: Polymorphisms in candidate genes related to neurotransmission and appetite regulation continue to be investigated for associations with AIWG, while novel findings have emerged from GWAS, gene expression, and epigenetic studies. Evidence remains inconsistent due to limited replication, methodological variability, sparse ancestry data, and geographical underrepresentation. No single genetic variant is ready for clinical use, and multi-omic and multi-ancestry models are needed to improve prediction and clinical utility.

Humans↗
PubMed2026

Exposure to size-specific particulate matter accelerates DNA methylation aging in people with HIV.

BACKGROUND: People with HIV (PWH) face accelerated aging and increased health risks, with DNA methylation age (DNAmAge) as a critical senescence biomarker. Particulate matter is linked to DNAmAge acceleration (DNAmAA) in general population, but its impact in PWH remains unstudied. METHODS: Thirty-two PWH from Wuhan, China, were enrolled in a prospective panel study with follow-up, and each participant underwent at least two repeated measurements during the study period. Portable air quality monitor measured PM 1 , PM 2.5 , and PM 10 exposures 72 h preblood sampling. We analyzed genome-wide DNA methylation in peripheral blood and calculated six AA metrics. Linear mixed-effects and weighted quantile sum regression models evaluated associations between particulate matter exposure and DNAmAA. RESULTS: Significant associations between particulate matter exposure and DNAmAA were observed at various lag windows. For every 10 μg/m 3 increase in 24-h average PM 2.5 , Hannum DNAmAA, Pheno DNAmAA, Grim DNAmAA, SkinBlood DNAmAA, and Elastic DNAmAA increased by 0.266 years [95% confidence interval (CI): 0.035-0.480], 0.421 years (95% CI: 0.032-0.701), 0.336 years (95% CI: 0.073-0.546), 0.295 years (95% CI: 0.021-0.495), and 0.254 years (95% CI: 0.034-0.445), respectively. PM 10 contributed most substantially to the cumulative PM effect on epigenetic AA in the lag0-24 h window. CONCLUSION: Short-term particulate matter exposure, particularly PM 10 , significantly accelerates epigenetic aging in PWH, highlighting the need to integrate air quality management into healthy aging strategies for this vulnerable population.

China↗
PubMed2026

Human endogenous retroviruses leading to autoimmune diseases.

Human endogenous retroviruses (HERVs) comprise approximately 8% of the human genome and were long regarded as inert remnants of ancestral retroviral infections. Increasing evidence indicates that HERVs are active genomic elements capable of influencing transcriptional programs, modulating immune responses, and contributing to disease pathogenesis. Under physiological conditions, HERV expression is tightly controlled by epigenetic mechanisms; however, infections, chronic inflammation, aging, and diverse environmental stimuli can promote HERV reactivation. HERV-derived RNAs and proteins engage innate immune sensors and trigger antiviral-like responses through mechanisms of viral mimicry, leading to activation of type I interferon and other inflammatory pathways. HERV dysregulation has been associated with disease-relevant immune pathways. This review summarizes recent advances linking HERVs to autoimmune disease pathogenesis and discusses their potential translational relevance as biomarkers and therapeutic targets.

Humans↗
PubMed2026

Strategies for mosaic variant calling in brain disorders.

The human brain is a genomic mosaic, where postzygotic mutations arising from embryogenesis to senescence drive diverse neurodevelopmental and neurodegenerative diseases. Because of numerous sequencing artifacts at ultralow variant allele frequencies (VAFs), detecting these variants remains a significant analytical challenge. This review focuses on single-nucleotide variants and small indels, summarizing current strategies for aligning sampling methods, including bulk, laser capture microdissection, and single-cell genomics, with the expected clonal architecture of the brain. It emphasizes that mosaic detection sensitivity is fundamentally constrained by sequencing depth, since even the most advanced algorithms cannot identify variants not physically represented in the sequencing library. The review further recommends the selection of variant calling algorithms based on validated VAF detection performance, matching tools like MuTect2 and MosaicForecast to their optimal performance ranges. Furthermore, we discuss how multitissue sampling, as emphasized by the SMaHT project, addresses the matched-control dilemma and supports accurate variant classification via cross-tissue VAF gradients. Integrating these established pipelines with multiomics modalities, including transcriptomic and epigenetic data, could advance the field toward a functional understanding of how the somatic genome impacts human brain health and disease.

Humans↗
PubMed2026

Insights into the regulation of the HOTAIR proximal promoter.

HOTAIR (HOX transcript antisense RNA) is a HOXC-cluster long intervening non-coding RNA (lincRNA) whose cancer relevance is tightly coupled to how its transcription is wired into hormone, hypoxia, inflammatory, and developmental signaling. HOTAIR is known to associate with cancer cell proliferation, motility, tumor invasion, and metastasis. The present mini-review focuses on the regulatory architecture and mechanistic complexity of HOTAIR transcriptional regulation, with emphasis on three organizing principles. First, we consider the impact of promoter choice between a canonical proximal promoter (P1), which supports the 2.2-2.4 kb transcript, and an alternative upstream promoter/TSS (P2), which contributes to context-dependent transcription initiation. Second, we examine the long-distance enhancer-promoter communication between HOTAIR distal enhancer and P1/P2. Third, we summarize the recent epigenetic and epi-transcriptomic mechanisms involved in HOTAIR transcript initiation and elongation. A combination of these events determines isoform-specific transcription to govern cell-type-, context-, and cancer specific modulation of HOTAIR expression that promotes tumor formation and cancer progression. Finally, the review proposes how large-scale RNA datasets, long-read sequencing, and isoform-specific studies can refine our understanding of this versatile lincRNA's regulation.

Humans↗
PubMed2026

Deciphering CD8+ T cell exhaustion in human cancers through single-cell and spatial transcriptomics.

Exhausted CD8+ T cells (Tex) within the tumor microenvironment (TME) represents a critical barrier limiting anti-tumor immune responses. Tex cells are characterized by upregulated inhibitory immune checkpoint receptors, reduced cytotoxicity, and functional heterogeneity. Their genomic features and regulatory networks remain poorly defined, and only a minority of patients respond to immune checkpoint blockade (ICB) therapy. Single-cell RNA sequencing (scRNA-seq), through high-resolution transcriptomic profiling, has revealed diverse Tex subpopulations, identified subpopulation-specific marker genes and regulatory pathways. Spatial transcriptomics has further mapped the spatial distribution of Tex and their interaction networks with immune cells, tumor cells, and stromal cells, elucidating the impact of spatial heterogeneity on Tex functionality. Current studies indicate that the exhausted state of Tex is dynamic and modifiable, with functional differences among subpopulations closely associated with tumor progression and therapeutic response. However, the genomic characteristics, epigenetic regulation, and spatial interaction mechanisms of Tex require further exploration. This review summarizes recent advances in high-resolution omics technologies for precisely dissecting Tex heterogeneity, functional features, and interactions with other cells. It emphasizes the central value of optimizing Tex-targeted tumor immunotherapy strategies, providing theoretical foundations and directional guidance for developing more effective anti-tumor immunotherapies.

Humans↗
PubMed2026

Hepatotoxicity of OBS: A review of the emerging PFOS substitute.

As an alternative to perfluorooctanesulfonic acid (PFOS), sodium perfluorononenyl oxobenzene sulfonate (OBS) is widely used due to its cost-effectiveness. Multiple studies have shown that the liver is a classic target organ for OBS. However, there is currently no systematic review on the hepatotoxic effects of OBS. This review systematically summarizes the exposure characteristics of OBS in the environment and human populations, as well as its mechanisms of liver toxicity. In vivo studies consistently demonstrate that OBS induces hepatotoxic effects, such as hepatomegaly, vacuolization, elevated serum transaminases, and lipid dysregulation, though the manifestation of these phenotypes varies across species and exposure routes. In vitro evidence further shows that OBS reduces cell viability and survival, and triggers necrosis accompanied by inflammation. Mechanistically, oxidative stress, inflammatory signaling, and metabolism disorder are implicated. Critically, most existing work addresses subacute or subchronic exposure, leaving a gap in chronic risk assessment for long-term, low-dose OBS exposure. Moreover, mechanistic studies have focused predominantly on downstream transcriptional and signaling changes, with limited exploration of upstream epigenetic controls. Overall, this study aims to provide a comprehensive reference for future toxicological investigations and liver injury risk assessments related to OBS exposure.

Humans↗
PubMed2026

Targeting TP53 in triple-negative breast cancer: Molecular pathogenesis, therapeutic implications, and emerging pharmacological strategies.

Triple-negative breast cancer (TNBC) remains a highly aggressive and therapeutically challenging subtype, defined by the absence of oestrogen, progesterone, and HER2 expression. Tumour Protein 53 (TP53) mutations represent the most frequent genetic alteration, occurring in over 80% of cases and driving tumour initiation, progression, and therapeutic resistance. Mutant p53 proteins not only lose canonical tumour-suppressive functions but also often acquire gain-of-function (GOF) oncogenic properties that promote metastasis, genomic instability, and resistance to mechanisms like ferroptosis. This review examines the biological role of TP53 in TNBC pathogenesis and evaluates emerging pharmacological strategies aimed at targeting these vulnerabilities. Key approaches include the pharmacological reactivation of mutant p53 using small molecules such as APR-246, COTI-2, and the mutation-specific reactivator rezatapopt (PC14586), which has shown significant clinical tumour reduction in Y220C-mutant patients. Other strategies involve targeted protein degradation, the exploitation of synthetic lethal interactions (e.g., Chk1 or Aurora kinase B inhibition), and the use of natural products like cryptolepine or piperine derivatives. Recent clinical evidence further highlights the potential of combining epigenetic agents like decitabine with chemotherapy in TP53-mutant populations. Integrating TP53 mutation status into biomarker-driven treatment paradigms is a pivotal step toward achieving precision oncology and improving clinical outcomes for patients with TNBC.

Precision oncology↗
PubMed2026

To longevity and beyond: A systems view of aging and stress resilience.

Aging is a dynamic and time-dependent process characterized by progressive functional decline across biological systems. Key hallmarks, including genomic instability, telomere attrition, loss of proteostasis, mitochondrial dysfunction, and immunosenescence, have been widely described, each reflecting distinct yet interconnected mechanistic frameworks. Rather than acting in isolation, these processes arise from complex interactions among cellular stressors, impaired repair mechanisms, and the cumulative burden of maladaptive responses. This system-level perspective explains the inter-individual variability in aging trajectories. Centenarians represent an extreme and informative model of successful aging, in which the balance between damage accumulation and repair is shifted toward the maintenance of physiological function. Their exceptional longevity is supported by coordinated genetic, epigenetic, metabolic, and immunological adaptations that enhance resilience to age-related stressors. Here, we summarize the biological drivers and theoretical frameworks of aging within an integrative context, focusing on mechanisms associated with extended healthspan in centenarians. We also examine the contribution of major animal models, highlighting their complementary roles in elucidating conserved and species-specific aging pathways. Overall, aging outcomes reflect a dynamic equilibrium between damage and repair processes. Understanding how this balance is modulated in long-lived individuals may inform strategies to promote healthy aging and delay the onset of age-related diseases.

Humans↗
PubMed2026

UNCX/SIN3A-Mediated H4K8 decrotonylation suppresses FOXO3 to drive TNBC progression and docetaxel resistance.

Triple-negative breast cancer (TNBC) remains a clinically challenging subtype characterized by aggressive behavior and limited treatment options. Though docetaxel remains a cornerstone chemotherapy for TNBC, the frequent emergence of resistance highlights the urgent need to identify novel therapeutic targets. In this study, we report that uncoordinated homeobox (UNCX) is upregulated in docetaxel-resistant breast cancer cells, genomically amplified in breast cancer, and associated with poor survival in breast carcinoma patients. Functional studies revealed that UNCX promotes breast cancer cell proliferation, migration and reduces the docetaxel sensitivity. Mechanistically, UNCX functions as a transcriptional repressor by recruiting the SIN3A complex. Genome-wide profiling indicated that the UNCX/SIN3A complex directly binds to the promoters of tumor-suppressor genes including FOXO3, and represses their transcription by removing histone H4K8 crotonylation (H4K8cr). Additionally, the UNCX/SIN3A complex enhances FOXO3 phosphorylation and inhibits its nuclear translocation, further inhibiting its activity. Notably, SIN3A knockdown, FOXO3 overexpression, or crotonylation restoration effectively reverses UNCX-induced malignant phenotypes. These findings collectively establish the UNCX/SIN3A-H4K8cr-FOXO3 axis as a pivotal epigenetic regulator of TNBC progression and chemoresistance, revealing new avenues for targeted therapeutic development against this aggressive breast cancer subtype.

Humans↗
PubMed2026

Mechanistic Insights Into the Association Between Gut Microbiota Diversity and Atherosclerosis, Acute Coronary Syndrome, and Peripheral Arterial Disease Progression.

BACKGROUND: The gut microbiome has emerged as a potential contributor to cardiovascular diseases (CVDs), including atherosclerosis, acute coronary syndrome (ACS), and peripheral arterial disease (PAD). While observational studies link dysbiosis to CVD, causal relationships remain uncertain. METHODS: This narrative review synthesizes evidence from human observational studies, clinical interventions, and experimental models to distinguish association from mechanistic plausibility and clinical causality. Literature was searched through July 2026 in PubMed/MEDLINE, Web of Science, and Scopus. RESULTS: Microbial metabolites-including trimethylamine N-oxide (TMAO), short-chain fatty acids (SCFAs), bile acids, and lipopolysaccharide (LPS)-modulate endothelial function, immune cell programming, platelet activity, and plaque stability through receptor-mediated signaling and epigenetic regulation. SCFAs demonstrate potentially protective effects via GPCR and HDAC pathways, while TMAO is associated with atherothrombotic risk. However, much mechanistic evidence derives from preclinical studies. Heterogeneity from diet, geography, host characteristics, renal function, and medications substantially influences microbiota-CVD associations. CONCLUSION: The gut-vascular connection is biologically plausible, but definitive clinical causality remains unproven. Microbiome-directed therapies (dietary modulation, pre/pro/synbiotics, targeted metabolite inhibition) are investigational. Prospective, standardized, adequately powered human studies with clinically meaningful outcomes are essential before routine cardiovascular application.

Gastrointestinal Microbiome↗
PubMed2026

3D epigenomic remodelling mediated by Foxa1 drives gemcitabine resistance in pancreatic cancer.

Gemcitabine remains a cornerstone treatment for pancreatic ductal adenocarcinoma (PDAC), yet the emergence of resistance constitutes a major clinical challenge with poorly understood epigenomic mechanisms. Here, we identified the pioneer transcription factor Foxa1 as a master regulator of gemcitabine resistance through multi-omics analysis. Mechanistically, Foxa1 drives widespread super-enhancer (SE) reprogramming and 3D genome remodelling in resistant cells, which coordinately activates the expression of key resistance genes, notably Rrm1 and Cdadc1. This is accompanied by increased chromatin accessibility, elevated H3K27ac enrichment at SEs, and enhanced Foxa1 binding at regulatory elements. Moreover, post-translational stabilization of Foxa1 via USP7-mediated deubiquitination sustains this epigenomic program. Genetic ablation of Foxa1 or specific SE regions near Rrm1 resensitizes resistant cells to gemcitabine. Building upon this mechanism, we demonstrate that bromodomain and extraterminal (BET) inhibitors, which disrupt SE function, potently reverse resistance. Notably, the clinical-stage BET inhibitor AZD5153, in combination with gemcitabine, achieves robust tumor suppression and overcomes resistance in cell-derived xenograft (CDX) models by dismantling the Foxa1-mediated resistant transcriptome and reinvigorating drug sensitivity. Our findings establish Foxa1-orchestrated enhancer reprogramming as a fundamental mechanism of gemcitabine resistance and unveil a promising epigenetic therapy to restore treatment efficacy in PDAC.

Hepatocyte Nuclear Factor 3-alpha↗
PubMed2026

Mechanisms linking the gut microbiota to colorectal cancer development and progression.

Colorectal cancer remains a leading cause of global cancer mortality, with a concerning rise in early-onset cases driven by complex interactions between environmental exposures, lifestyle factors, and host genetics. Mounting evidence indicates that gut microbiota dysbiosis critically modulates this oncogenic process, acting as an active participant rather than a passive bystander. This review systematically synthesizes the dichotomous roles of the intestinal microbiome in colorectal tumorigenesis through the conceptual framework of the driver-passenger model. We discuss how early initiating driver bacteria, such as Polyketide synthase-positive Escherichia coli and enterotoxigenic Bacteroides fragilis, compromise mucosal barriers, induce chronic mucosal inflammation, and inflict direct genomic instability. As the local tumor microenvironment undergoes profound metabolic remodeling, opportunistic passenger pathogens, notably Fusobacterium nucleatum, become enriched, further promoting cellular proliferation and facilitating tumor immune evasion. Conversely, protective commensals, exemplified by Clostridium butyricum and Streptococcus thermophilus, exert robust tumor-suppressive effects through multifaceted mechanisms. These beneficial microbes actively antagonize malignant progression by redirecting tumor metabolic fluxes toward oxidative stress, orchestrating deep epigenetic reprogramming, and degrading core oncoproteins to reverse chemoresistance. Transitioning from fundamental mechanisms to clinical application, we evaluate a comprehensive spectrum of microbiota-targeted interventions, encompassing non-invasive diagnostic biomarkers, fecal microbiota transplantation, engineered bacteria, phage therapy, and postbiotics. Finally, we critically address the formidable translational challenges associated with microbial heterogeneity, long-term safety, and regulatory standardization, aiming to provide a balanced perspective on integrating microbiome-based strategies into next-generation precision oncology for colorectal cancer.

Humans↗
PubMed2026

Genome-wide association study of estimated glomerular filtration rate using repeated measurements in the Taiwan Biobank.

BACKGROUND: Chronic kidney disease (CKD) is a major global public health issue, with genetic factors playing a significant role in kidney function. Although genome-wide association studies (GWAS) have identified numerous loci associated with estimated glomerular filtration rate (eGFR), most studies relied on a single time-point measurement, which limits the capacity to account for within-individual measurement variability. METHODS: We performed a repeated-measurement GWAS in the prospective Taiwan Biobank (Taiwanese ancestry; n = 25,004) using two repeated creatinine-based eGFR measurements. Repeated eGFR values were analyzed using a linear mixed-effects model with a subject-specific random intercept and time-varying covariates, providing a more precise estimate of eGFR level. Identified loci underwent functional annotation (expression quantitative trait locus, deleteriousness prediction, and epigenetic markers) and were compared with results from a single-measurement GWAS. RESULTS: Six loci associated with eGFR were identified, including four previously reported regions (1q22, 4q21.1, 11p14.1, and 17q21.2) and two additional loci (6p21.32 and 15q24.2). Functional annotation implicated several candidate genes-such as MUC1/EFNA1, SHROOM3, HLA-DQB1, MPPED2, NRG4, and PGAP3/FBXL20-in the regulation of kidney function. CONCLUSION: Incorporating repeated eGFR measurements into GWAS may improve phenotypic precision for identifying genetic associations with kidney function. This study identified eGFR-associated loci and biologically plausible candidate genes in a Taiwanese population, which require further replication and functional validation.

Chronic kidney disease↗
PubMed2026

ChIP-seq profiling identifies diapause-regulated H3K27me3 targets in the fat body of Culex pipiens.

Culex pipiens, a principal vector of significant arboviruses, survives winter through diapause, a hormonally controlled inactive phase that enhances endurance under severe cold circumstances. Recent data suggests that epigenetic processes, namely histone post-translational modifications (hPTMs), play a crucial role in regulating seasonal dormancy. Prior studies from our laboratory indicated a decrease in the methylation of Histone 3 (H3K27me3) in diapausing fat body tissue, associated with elevated expression of the histone demethylase UTX. Nonetheless, the precise genomic areas impacted by these chromatin alterations remained unidentified. We used chromatin immunoprecipitation coupled with high-throughput sequencing (ChIP-seq) to delineate the genome-wide distribution of H3K27me3 across fat body chromatin in diapausing (D) and non-diapausing (ND) female Cx. pipiens. Notably, the higher signal at transcription start sites (TSSs) reflects localized redistribution rather than a global decrease, as diapausing fat bodies retain less H3K27me3 overall but concentrate it at promoters. To investigate the functional significance of these chromatin alterations, we confirmed a number of target loci via ChIP-qPCR and assessed gene expression with qRT-PCR. We identified many critical genes that were markedly increased in diapausing mosquitoes, exhibiting an inverse relation to H3K27me3 enrichment. Our data demonstrates different H3K27me3 chromatin landscapes between diapausing and non-diapausing Cx. pipiens, corroborating a hypothesis of selective, locus-specific repression in the non-diapause state and its targeted removal during diapause to permit activation of dormancy-associated genes. These results suggest that chromatin remodeling is a core driver of the diapause switch.

Animals↗
PubMed2026

Measurable Residual Disease and the Unresolved Biology of Leukemic Stem Cells.

Measurable residual disease (MRD) testing has transformed the management of hematologic cancers by enabling detection of residual malignant cells after therapy. Current approaches rely on qPCR and next-generation sequencing to monitor leukemia-associated somatic mutations, while multiparameter flow cytometry identifies aberrant leukemic immunophenotypes. Although these methods provide valuable prognostic and therapeutic information, MRD negativity remains an imperfect surrogate for cure. Most MRD platforms evaluate CD45+, rapidly dividing leukemic populations and fail to detect quiescent cells that may survive cytotoxic therapies which efficiently target proliferating hematopoietic cells. Relapse frequently occurs despite deep molecular remission, suggesting persistence of rare leukemic stem cells (LSCs) that are intrinsically resistant to chemotherapy and targeted therapies. The paradox of relapse despite molecular remission could be explained by the presence of very small embryonic-like stem cells (VSELs) which are pluripotent, quiescent stem cells sitting at the top of cellular hierarchy in multiple adult tissues including bone marrow. A pluripotent VSEL divides through asymmetrical cell division to give rise to two cells of different sizes and fates, smaller cell is to self-renew while the bigger is lineage-restricted and tissue-committed progenitor which undergoes extensive epigenetic changes, divides rapidly and undergoes clonal expansion before further differentiation. Dysfunctions of VSELs initiate both solid and hematologic cancers. Based on this view, somatic mutations monitored during MRD assessment possibly represent downstream consequences of clonal expansion rather than the initiating drivers of disease persistence. Thus, exclusive monitoring of somatic mutations and CD45 + leukemic populations possibly overlook rare, small-sized, CD45- VSELs that contribute to therapeutic resistance and relapse.

Humans↗