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PubMed2026

Quality of life with palbociclib plus tamoxifen in hormone receptor-positive, HER2-negative advanced breast cancer: results from PATHWAY, an Asian international, double-blind, randomized phase 3 trial.

BACKGROUND: In the Asian international PATHWAY trial, palbociclib-tamoxifen demonstrated improved progression-free survival compared with placebo-tamoxifen in patients with HR+/HER2- locally advanced or metastatic breast cancer (ABC). This analysis compared quality of life (QoL) between treatment arms. METHODS: Pre/peri or postmenopausal women with HR+/HER2- ABC were randomly assigned 1:1 to receive palbociclib-tamoxifen or placebo-tamoxifen. Patient-reported outcomes were assessed on day 1 of cycles 1 (baseline), 4, and 7, and at the end of treatment (EOT) using the EORTC QLQ-C30 and QLQ-BR23 questionnaires. Least-square mean (LSM) changes in scores from baseline were calculated. Kaplan-Meier method was used to calculate time to deterioration (TTD) in the minimally important difference (MID) in the pain subscale. RESULTS: In the comparison between treatment arms, no significant differences were observed in LSM changes in scores from baseline in global QoL (cycle 4: 0.70 [95% confidence interval (CI): -5.00, 6.41]; cycle 7: 2.17 [95% CI: -4.14, 8.48]; EOT: -5.19 [95% CI: -11.64, 1.26]). For both the EORTC QLQ-C30 and QLQ-BR23 functional and symptom subscales, no clinically meaningful differences between treatment arms were found in the LSM changes in scores from baseline. Median TTD in the MID in the pain subscale was 32.5 months (95% CI: 11.7, not estimable) for the palbociclib-tamoxifen arm and 21.2 months (95% CI: 5.5, 43.5) for the placebo-tamoxifen arm (hazard ratio = 0.729 [95% CI: 0.467, 1.138]). CONCLUSIONS: The combination of palbociclib and tamoxifen delayed deterioration in patients' QoL while they experienced reduced risk for disease progression. TRIAL REGISTRATION: ClinicalTrials.gov: NCT03423199; study registration date: February 6, 2018.

Humans↗

PubMed2026

Fibroblast growth factor 21 prevents catecholaminergic arrhythmias in a mouse model of PKP2 arrhythmogenic cardiomyopathy.

BACKGROUND: Pathogenic variants in plakophilin-2 (PKP2) cause arrhythmogenic cardiomyopathy (ACM) with intracellular calcium dysregulation as a major component of its arrhythmia phenotype. Recent adeno-associated virus (AAV)-based PKP2 gene therapy has shown promising results in a few different PKP2-associated ACM models. Fibroblast growth factor 21 (FGF21) has multiple cardioprotective effects and has recently emerged as a promising therapeutic agent for cardiovascular disease. OBJECTIVE: This study aimed to assess the efficacy and impact on calcium regulation of a novel AAV serotype 8 (AAV8)-based FGF21 gene therapy on adult cardiac-specific, tamoxifen-activated PKP2 knockout (PKP2-cKO) mice. METHODS: Experiments were performed using a PKP2-cKO murine model. AAV8-FGF21 was delivered to adult mice by a single tail vein injection 7 days before tamoxifen-activated PKP2-cKO. Cardiac functions were monitored using echocardiography and electrocardiography. Intracellular calcium transients were investigated in acute isolated adult mouse cardiomyocytes, and calcium fluorescent signals were acquired using the IonOptix system. RESULTS: Loss of PKP2 expression caused cardiac mechanical dysfunction and proarrhythmic phenotype in adult mouse models. AAV-mediated delivery of FGF21 mitigated the progression of biventricular structural changes, decreased the occurrence of adrenergic arrhythmias, and rescued intracellular calcium imbalance in the setting of PKP2 haploinsufficiency. In contrast, acute in vitro FGF21 treatment for 1 hour had no effect on intracellular calcium transients. CONCLUSION: These beneficial effects of AAV8-FGF21 on the PKP2-ACM phenotype suggest a therapeutic landscape for various targeted cardiomyopathies.

Animals↗

PubMed2026

Efficacy, acceptability, and related outcomes of pharmacological interventions for acute bipolar mania: a systematic review and dose-related network meta-analysis across different age groups.

BACKGROUND: Acute bipolar mania carries negative social and economic consequences. We investigated the comparative efficacy/response/acceptability of pharmacological interventions for acute bipolar mania, considering dose effects across different age groups. METHODS: We conducted a network meta-analysis (NMA) to search for randomized controlled trials (RCTs) comparing pharmacological interventions with one another or placebo in acute bipolar mania patients, indexed in PubMed/MEDLINE, Embase, Web of Science, and Scopus (from inception through 2025.12.24). Co-primary outcomes were change in manic symptoms/response/and acceptability. Tolerability/remission and rate of adverse events were secondary outcomes. Confidence-In-Network-Meta-Analysis was likewise appraised. RESULTS: 113 RCTs, encompassing 49 distinct treatment combinations, included 20,666 participants. Sensitivity analysis retaining only low-risk-of-bias studies and excluding outliers for possible effect modifiers indicated that risperidone 3 mg/day(SMD = -7.57;95%C.I. = -8.25;-5.85); tamoxifen 160 mg/day(SMD = -1.73;95%C.I. = -2.32;-1.13); rivastigmine 3 mg/day(SMD = -1.13;95%C.I. = -1.06;-0.58); haloperidol 30 mg/day(SMD = -0.96;95%C.I. = -1.25;-0.75); valproate 750 mg/day(SMD = -0.76;95%C.I. = -1.48;-0.58); tamoxifen 40 mg/day(SMD = -0.75;95%C.I. = -1.41;-0.59); celecoxib 400 mg/day(SMD = -0.74;95%C.I. = -1.20;-0.38); paliperidone extended-release 12 mg/day(SMD = -0.62; 95%C.I. = -0.91;-0.32); olanzapine 15 mg/day(SMD = -0.59;95%C.I. = -0.60;-0.38); olanzapine 20 mg/day(SMD = -0.52;95%C.I. = -0.66;-0.38); risperidone 4 mg/day(SMD = -0.53;95%C.I. = -0.76;-0.29); allopurinol 600 mg/day(SMD = -0.54;95%C.I. = -0.67;-0.22); cariprazine 12 mg/day(SMD = -0.49;95%C.I. = -0.66;-0.33); risperidone 4.2 mg/day(SMD = -0.46;95%C.I. = -0.75;-0.17); lithium 1500 mg/day(SMD = -0.42;95%C.I. = -0.57;-0.28); ziprasidone 160 mg/day(SMD = -0.49;95%C.I. = -0.68;-0.31); asenapine 20 mg/day(SMD = -0.38;95%C.I. = -0.53;-0.22); haloperidol 8 mg/day(SMD = -0.34;95%C.I. = -0.63;-0.05); aripiprazole 15 mg/day(SMD = -0.33;95%C.I. = -0.61;-0.06) outperformed placebo. Ziprasidone 160 mg/day, celecoxib 200 mg/day, asenapine 20 mg/day, and asenapine 10 mg/day proved more efficacious than placebo in children. No statistically significant differences were reported between treatments and placebo for response/remission/acceptability/tolerability, and manic/hypomanic switch. A meta-regression of efficacy effect sizes against the adapted AMSTAR-Plus content scores showed that larger SMDs were associated with lower AMSTAR scores, indicating lower study quality, warranting further caution for such large efficacy estimates. CONCLUSIONS: Our findings are consistent with previous NMAs and current guidelines, expanding the current knowledge base while concurrently appraising different drugs, doses, and age groups.

Humans↗

PubMed2024

The Protective Role of DDIT4 in Helicobacter pylori-induced Gastric Metaplasia Through Metabolic Regulation of Ferroptosis.

BACKGROUND & AIMS: Helicobacter pylori (H pylori) infection is a significant factor leading to gastric atrophy, metaplasia and cancer development. Here, we investigated the role of the stress response gene DDIT4 in the pathogenesis of H pylori infection. METHODS: Cell lines, transgenic mice, and human tissue samples were implemented. Proteomics were performed on Ddit4+/+ and Ddit4-/- mice infected with H pylori strain PMSS1. C57BL/6 mice were administered with tamoxifen to induce gastric metaplasia. Stomach tissues were analyzed for histopathologic features, reactive oxygen species, Fe2+, lipid peroxidation, expression of DDIT4, and ferroptosis-related proteins. RESULTS: DDIT4 expression was upregulated at 6 hours but significantly decreased at 24 hours in response to H pylori infection in gastric epithelial cells. Gastric DDIT4 were downregulated in INS-GAS mice at 4 months post H pylori infection. Notably, H pylori infection led to more severe gastric metaplasia lesion in Ddit4-knockout mice. The proteomic profiling revealed an increase in ferroptosis in the gastric tissues of infected Ddit4-deficient mice, compared with infected wild-type mice. Mechanistically, knockout of DDIT4 promoted H pylori-induced ferroptosis through the accumulation of lipid peroxides and ROS levels, and alterations in proteins such as GPX4, ALOX15, and HMOX1. Overexpression of DDIT4 counteracted H pylori-induced stem cell marker CD44V9 through modulation of ferroptosis. Similarly, in another mouse model of gastric metaplasia treated with tamoxifen, as well as in human GIM tissues, we observed the loss of DDIT4 and induction of ferroptosis. CONCLUSIONS: Our results indicate that DDIT4 serves as a protective factor against H pylori-induced gastric metaplasia by metabolic resistance to ferroptosis.

Ferroptosis↗

PubMed2025

High p62 and ALDH1A3 Reduce the Effectiveness of Endocrine Therapy in Luminal B Breast Cancer.

BACKGROUND/AIM: High expression of p62 and ALDH1A3 indicates a poor clinical outcome in luminal B breast cancer, and p62 is involved in the progression of ALDH1-positive luminal B breast cancer stem cells. However, the association between endocrine therapy and high p62 and ALDH1A3 expression, in luminal B breast cancer remains unclear. MATERIALS AND METHODS: Two datasets with gene expression and clinical data for patients with primary breast cancer (METABRIC, n=2,509; The Cancer Genome Atlas, n=1,084) were downloaded and statistically analyzed. To evaluate the association between the p62 and ALDH1A3 expression levels and endocrine therapy, including tamoxifen and aromatase inhibitor, in patients with luminal B breast cancer, disease-specific survival was examined using Kaplan-Meier and multivariate Cox regression analyses. RESULTS: Patients with p62 high ALDH1A3 high luminal B breast cancer treated with endocrine therapy exhibited a poor prognosis. Moreover, patients with p62 high ALDH1A3 high luminal B breast cancer treated with tamoxifen showed a trend towards a poor prognosis, but those treated with aromatase inhibitors showed a significantly poor prognosis. These results suggest that endocrine therapy, especially aromatase inhibitors, exhibits a reduced effectiveness against p62 high ALDH1A3 high luminal B tumors. CONCLUSION: p62 and ALDH1A3 could be used together as a prognostic biomarker for predicting the efficacy of endocrine therapy for luminal B breast cancer.

ALDH1A3↗

PubMed2026

Integrin α3 (ITGA3) expression across breast cancer subtypes: Prognosis and therapeutic relevance.

BACKGROUND: Integrin α3 (ITGA3), which heterodimerizes with integrin β1, has emerged as a potential biomarker and therapeutic target in several epithelial malignancies; however, its clinical relevance in breast cancer remains incompletely characterized. This study evaluated ITGA3 expression across breast cancer molecular subtypes and assessed its prognostic and predictive significance. METHODS: Immunohistochemistry (IHC) was performed on archival breast cancer specimens using tissue microarrays (n = 148) and whole-tissue sections (n = 21). Complete clinicopathologic and outcome data were available for 108 patients, including hormone receptor-positive/human epidermal growth factor receptor 2-negative, HER2-positive, and triple-negative breast cancer (TNBC) subtypes. ITGA3 expression was quantified using H-scores and correlated with clinicopathologic features and survival outcomes. Independent transcriptomic analyses were conducted using the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) and the Cancer Genome Atlas Breast Invasive Carcinoma (TCGA-BRCA) cohorts to evaluate ITGA3 mRNA expression, co-expressed signaling pathways, and associations with therapeutic response. RESULTS: ITGA3 protein expression was detected in 85.2% of breast cancer specimens and was significantly higher in HR-positive/HER2-negative and HER2-positive tumors compared with TNBC (p < 0.0050). High ITGA3 expression was associated with shorter recurrence-free survival (p < 0.0001). In the METABRIC cohort, tumors with ITGA3 alterations demonstrated significantly worse relapse-free survival (p < 0.0001) and overall survival (p < 0.0500). Transcriptomic analyses revealed that ITGA3 co-expressed with estrogen receptor 1(ESR1), erb-b2 receptor tyrosine kinase 2 (ERBB2), and luminal markers, along with enrichment of estrogen receptor and phosphoinositide 3-kinase-protein kinase B-mechanistic target of rapamycin (PI3K/AKT/mTOR) signaling pathways. ITGA3 expression was not predictive of response to tamoxifen or trastuzumab. CONCLUSION: Elevated ITGA3 expression is associated with breast cancer recurrence and poor clinical outcomes, supporting its potential role as a prognostic biomarker and candidate therapeutic target.

Biomarkers↗

PubMed2026

Integrating Genomic and Nongenomic Data to Stratify the Risk of Contralateral Breast Cancer After Radiation Therapy.

PURPOSE: Women treated with radiation therapy (RT) for breast cancer have an increased risk of developing radiation-associated contralateral breast cancer (CBC). Predicting CBC events is challenging because of the complex interplay of genomic, treatment, personal, and clinical factors. This study investigated computational methods that integrate genome-wide single-nucleotide polymorphisms and nongenomic data to develop a risk stratification model for developing CBC in women treated with RT for their first primary breast cancer. METHODS AND MATERIALS: This study used a subset of the population-based Women's Environmental Cancer and Radiation Epidemiology study that included 633 CBC cases and 1253 individually matched unilateral breast cancer controls who were treated with RT and had single-nucleotide polymorphism data available from a genome-wide association study. The study population was split into training, validation, and test sets for rigorous modeling and validation. Three data integration methods were compared in terms of their ability to stratify CBC risk: (1) naive integration; (2) sequential integration; and (3) sequential iterative integration. A biological analysis of the final model was performed using gene set enrichment analysis and protein-protein interaction analysis with gene annotation information informed by the model. RESULTS: The best-performing integration method was the sequential iterative integration equipped with the mixed-effect random forest algorithm. This approach achieved an area under the curve of 0.64 to stratify CBC risk in the test set, representing moderate predictive power. Calibration analysis showed good agreement between the lowest and highest risk bins stratified using sorted predicted values in the test set, resulting in an odds ratio of 3.27 for both predicted and observed CBC occurrence. Gene set enrichment analysis and protein-protein interaction analysis revealed that genes with high importance scores were associated with pathways relevant to lipid and fatty acid metabolism as well as breast cancer sensitivity to tamoxifen. CONCLUSIONS: The mixed-effect random forest approach demonstrated the potential for integrating high-dimensional genomic and low-dimensional nongenomic data to stratify CBC risk.

Humans↗

PubMed2026

IDH3-dependent mitochondrial function in stromal fibroblasts suppresses malignant tumor growth.

Malignant solid tumors comprise not only cancer cells but also diverse non-cancerous stromal cells that shape the tumor microenvironment. The tricarboxylic acid (TCA) cycle has an overarching presence in providing substrates needed to drive the electron transport chain and, ultimately, ATP synthesis. However, it remains unclear which stromal cell lineages influence tumor growth through TCA-dependent mitochondrial function, and whether such activities act in a tumor-promoting or tumor-suppressive manner. Isocitrate dehydrogenase 3 (IDH3), a rate-limiting TCA cycle enzyme that generates NADH to support mitochondrial respiration, provides a genetic entry point to interrogate mitochondrial TCA-dependent function in stromal cells. In this study, we established a mouse model in which tamoxifen administration induces CreERT2-dependent knockout of the α subunit of IDH3 (IDH3α) in all somatic cells. Using this model with transplantation of Idh3a-intact murine cancer cells, we found that host Idh3a deficiency accelerated growth of murine MC38 tumors in a cancer cell line-dependent manner. Bone marrow chimera experiments indicated that hematopoietic lineages were not responsible for this phenotype, suggesting a contribution from tissue-resident non-hematopoietic stromal cells that are not replaced by bone marrow transplantation. Single-cell RNA sequencing of human tumor specimens revealed broad IDH3A expression across multiple tumor microenvironment compartments, including fibroblasts. Consistently, in vitro co-culture assays demonstrated that Idh3a-intact, but not Idh3a-KO, fibroblasts suppressed cancer cell proliferation in a contact-dependent manner. Together, these findings identify IDH3α-dependent mitochondrial function in fibroblasts as a critical determinant of tumor progression and suggest that stromal mitochondrial metabolism represents an important axis for modulating tumor behavior.

Cancer↗

PubMed2026

Functional perturbation reveals context-dependent contributions of nuclear receptors to drug-induced hepatic steatosis.

Drug-induced hepatic steatosis is mediated by diverse molecular mechanisms, yet several nuclear receptors have been proposed as molecular initiating events or early key events within adverse outcome pathways for hepatic steatosis. However, direct functional evidence supporting these mechanistic roles in human-relevant experimental systems remains limited. The present study evaluated the contribution of selected nuclear receptors to drug-induced hepatic steatosis using complementary human hepatic in vitro models. Stable short hairpin RNA-mediated knockdown of individual nuclear receptors was established in HepG2 and differentiated HepaRG cells, followed by exposure to representative steatogenic drugs, including valproic acid, amiodarone, tamoxifen, and rifampicin. In parallel, primary human hepatocyte spheroids were used to compare drug-induced lipid accumulation with direct pharmacological activation of individual nuclear receptor pathways. While depletion of multiple nuclear receptors markedly affected oleic acid-induced lipid accumulation, drug-induced steatogenic responses exhibited predominantly selective and compound-specific receptor dependencies. In differentiated HepaRG cells, nuclear receptor depletion influenced basal lipid homeostasis more strongly than valproic acid-induced lipid accumulation. Conversely, direct activation of liver X receptor and peroxisome proliferator-activated receptors α and γ in primary human hepatocyte spheroids induced robust lipid accumulation, whereas most steatogenic drugs produced comparatively modest responses. These findings demonstrate that the contribution of individual nuclear receptors to drug-induced hepatic steatosis is highly compound- and context-dependent and cannot be explained by a single conserved receptor pathway. This study provides functional evidence from complementary human-relevant hepatic models that supports refinement of hepatic steatosis adverse outcome pathways and highlights the value of targeted perturbation strategies for mechanistic toxicology.

Adverse outcome pathway, HepaRG↗

PubMed2025

In vivo CRISPR screening links NFKB1 to endocrine resistance in ER⁺ breast cancer.

Resistance to endocrine therapy (ET) remains a major clinical challenge in the treatment of estrogen receptor-positive (ER⁺) breast cancer, underscoring the need for novel therapeutic targets. To identify genetic drivers of ET resistance, we conducted an in vivo genome-wide CRISPR-Cas9 screen in MCF7 cells implanted into ovariectomized nude mice under estrogen-deprived conditions. NFKB1 emerged as a top candidate whose loss promoted estrogen-independent tumor growth and recurrence. Functional studies confirmed that NFKB1 deficiency enhanced tumorigenicity and conferred resistance to tamoxifen and fulvestrant both in vitro and in vivo. Mechanistically, transcriptomic and biochemical analyses revealed that NFKB1 loss activated canonical NF-κB signaling, leading to inflammatory gene induction and hyperactivation of ER signaling. Importantly, pharmacologic inhibition of NF-κB signaling restored ET sensitivity in NFKB1-deficient cells. Clinically, NFKB1 downregulation was enriched in ER⁺ breast tumors and associated with poor patient outcomes. Collectively, these findings establish NFKB1 as a key suppressor of ET resistance, uncover a mechanistic link between inflammation and ER reactivation, and highlight NF-κB signaling as a therapeutic vulnerability in NFKB1-deficient ER⁺ breast cancer.

Journal Article↗

PubMed2026

Aging and DNA damage are associated with the development of endothelial cell clonal expansion.

Endothelial dysfunction is a hallmark of vascular aging and a key contributor to cardiovascular disease. Although senescence has been widely studied as a terminal endothelial cell fate, recent evidence suggests that clonal expansion, the proliferative expansion of genetically identical cells, may also occur in aged tissues. We sought to determine whether endothelial clonal expansion increases with age, specifically at the atheroprone regions of the aorta, and to evaluate whether DNA damage promotes endothelial cell clonal expansion. Tamoxifen-inducible, endothelial-specific Cdh5-CreERT2 male and female mice were used to quantify clonal expansion in endothelial cells (ECs) across the aortic region in both young (4 mo) and aged (24 mo) mice. We further examined the effect of DNA damage by administering systemic doxorubicin (DOXO) to assess clonal dynamics in different aortic regions. Aging significantly increased EC clone size and the percentage of clonal ECs in atheroprone regions, particularly the minor arch, whereas only clone size increased in nonatheroprone regions. Systemic DOXO administration increased clone size across the aortic region without altering clonal recruitment, indicating selective amplification of preexisting clones. These findings suggest that clonal expansion is promoted by both aging and DNA damage. Clonal expansion may represent an underrecognized mechanism contributing to endothelial homogeneity and vascular remodeling during aging and in response to sublethal genomic stress.NEW & NOTEWORTHY Aging reshapes the vascular endothelium in unexpected ways. Using lineage tracing in mice, we show that endothelial cells undergo age-dependent clonal expansion, particularly in atheroprone regions exposed to disturbed blood flow. This process is amplified by DNA damage and reflects the selective expansion of preexisting clones rather than increased recruitment. Endothelial clonal expansion may represent an underrecognized mechanism driving vascular remodeling during aging and genotoxic stress.

Animals↗

PubMed2026

Impaired Glycolysis Leads to Defective Efferocytosis and Impaired Plaque Resolution in Tet2 Clonal Hematopoiesis.

BACKGROUND: Clonal hematopoiesis (CH) arising from mutations in hematopoietic genes has been identified as an important risk factor for atherosclerotic cardiovascular disease. Despite the established role of some CH mutations in promoting atherosclerosis progression, their role in clinically relevant LDL (low-density lipoprotein) lowering-induced plaque remodeling or regression has not been extensively studied. METHODS: To assess the effects of TET2 (tet methylcytosine dioxygenase 2) CH on plaque resolution, we prepared control or chimeric Tet2+/- CH mice with conditional deletion of Tet2 in hematopoietic stem cells during LDL lowering-induced plaque remodeling. After establishing atherosclerosis by Western diet feeding for 12 weeks in Ldlr-/- mice, Tet2 was deleted by tamoxifen injection, and hypercholesterolemia was either normalized to simulate clinical lipid management, or mice were continued on the Western diet. RESULTS: Unlike control mice, Tet2+/- CH mice failed to significantly reduce necrotic core area or increase fibrous cap thickness and showed impaired macrophage efferocytosis during LDL lowering. Single-cell RNA sequencing and gene set enrichment analysis of aortic cell populations revealed that Tet2 deficient monocyte/macrophage populations were defective in glycolysis, phagocytosis, and actin polymerization. Tet2-deficient bone marrow-derived macrophages and Tet2+/- induced pluripotent stem cell-derived human macrophages showed defective ability to sustain continuing rounds of efferocytosis. Bone marrow-derived macrophages displayed reduced apoptotic cell binding and internalization and impaired activity of Wiskott-Aldrich syndrome protein and SCAR (suppressor of cyclic AMP receptor) homolog complex mediated actin polymerization. We linked these defects to reduced anaerobic glycolysis and lactate levels and rescued them by lactate supplementation or by treatment with the HIF-1α (hypoxia-inducible factor 1α) activator molidustat. Molidustat treatment reversed the defects in necrotic core and fibrous cap formation during LDL lowering-induced plaque remodeling in Tet2+/- CH mice. Reduced plasma lactate levels were also shown in TET2 clonal hematopoiesis of indeterminate potential carriers in the UK Biobank. CONCLUSIONS: Our data identify impaired efferocytosis and glycolysis-lactate-actin polymerization pathways in advanced atherosclerosis as potential therapeutic targets to induce proresolving restructuring of the plaque immune cells and to promote beneficial atherosclerosis remodeling in subjects with TET2 CH.

LDL lowering↗

PubMed2026

Cardiomyocyte-Specific Plakophilin-2 Loss Is Sufficient to Induce Aging and Senescence of Nonmyocytes: Relevance to Arrhythmogenic Cardiomyopathy.

BACKGROUND: Pathogenic variants in PKP2 are the most common cause of familial arrhythmogenic right ventricular cardiomyopathy. This study tests whether plakophilin-2 (PKP2) deficiency only in cardiomyocytes is sufficient to provoke premature aging and proinflammatory senescence in nonmyocyte, cardiac resident cells. METHODS: We studied mice with cardiomyocyte-specific, tamoxifen-activated loss of PKP2 (cardiomyocyte-specific conditional knockout of plakophilin-2) using conventional and multiplex imaging, cytokine arrays, epigenetic clocks, spatial transcriptomics, expansion and structured illumination microscopy, and correlative data analysis. We examined nonmyocytes and cardiomyocytes for premature aging and senescence. RESULTS: We observed senescence-associated heterochromatin foci in nonmyocytes, predominantly in cells positive for α-smooth muscle actin staining. Cytokines in media of nonmyocyte cells were consistent with senescence-associated secretory phenotype. Epigenetic clocks identified premature aging. Multiplex immunohistochemistry showed nonmyocyte cells in niches, intermingled with cardiomyocytes. Spatial transcriptomics showed overrepresentation of senescence-associated secretory phenotype-related transcripts, predominantly in myocyte-rich areas of the left ventricle. Senescence-associated heterochromatin foci and increased epigenetic age were not found in cardiomyocytes from cardiomyocyte-specific conditional knockout of plakophilin-2 hearts, although we observed structural features associated with premature aging. Cross-reference analysis showed correlation between the cardiomyocyte-specific conditional knockout of plakophilin-2 cardiac proteome and that of mice 5 or 6 times their chronological age, as well as transcriptional signatures of neurodegenerative diseases. CONCLUSIONS: Loss of PKP2 expression only in adult cardiac myocytes is sufficient to induce proinflammatory senescence in nonmyocytes, and overall premature cardiac aging. This is the first study to intersect cellular senescence and premature aging with desmosomal arrhythmogenic cardiomyopathies. We speculate that cell-agnostic molecular signatures, biomarkers, and pharmacology of senescence and of neurodegenerative diseases may be relevant to diagnose or treat PKP2 arrhythmogenic right ventricular cardiomyopathy.

Animals↗

PubMed2025

Exome-wide association study reveals 7 functional variants associated with ex-vivo drug response in acute myeloid leukemia patients.

Acute myeloid leukemia (AML) is an aggressive blood cancer characterized by poor survival outcomes. Further, due to the extreme molecular heterogeneity of the disease, drug treatment response varies from patient to patient. The variability of drug response can cause unnecessary treatment in more than half of the patients with no or partial therapy responses leading to severe side effects, monetary as well as time loss. Understanding the genetic risk factors underlying the drug response in AML can help with improved prediction of treatment responses and identification of biomarkers in addition to mechanistic insights to monitor treatment response. Here, we report the results of the first Exome-Wide Association Study (EWAS) of ex-vivo drug response performed to date with 175 AML cases and 47 drugs. We used information from 55,423 germline exonic SNPs to perform the analysis. We identified exome-wide significant (p < 9.02 × 10- 7) associations for rs113985677 in CCIN with tamoxifen response, rs115400838 in TRMT5 with idelalisib response, rs11878277 in HDGFL2 with entinostat, and rs2229092 in LTA associated with vorinostat response. Further, using multivariate genome-wide association analysis, we identified the association of rs11556165 in ATRAID, and rs11236938 in TSKU with the combined response of all 47 drugs and 29 nonchemotherapy drugs at the genome-wide significance level (p < 5 × 10- 8). Additionally, a significant association of rs35704242 in NIBAN1 was associated with the combined response for nonchemotherapy medicines (p = 2.51 × 10- 8), and BI.2536, gefitinib, and belinostat were identified as the central traits. Our study represents the first EWAS to date on ex-vivo drug response in AML and reports 7 new associated loci that help to understand the anticancer drug response in AML patients.

Humans↗

PubMed2025

Investigating the molecular mechanisms, drug prediction, and validation of CCNA2 and MAD2L1 in esophageal squamous cell carcinoma based on bioinformatics.

OBJECTIVE: Aims to comprehensively investigate the expression patterns of CCNA2 and MAD2L1 in esophageal squamous cell carcinoma using bioinformatics methods. METHODS: Based on WGCNA analysis of gene mutation expression, methylation level distribution, mRNA expression and ESCC-related genes in public databases, were employed for investigating potential biomarkers for prognosis of esophageal squamous cell carcinoma(ESCC).Finally,. performing qRT-PCR and immunohistochemistry to validate. RESULTS: Ultimately identified 4 hub genes: CDK1, CCNA2,TOP2A and MAD2L1. Bioinformatics analysis showed high expression of these four genes in ESCC (P < 0.05). CCNA2 and MAD2L1 were selected for subsequent analysis based on literature.3.Single gene enrichment analysis revealed significant enrichment of CCNA2 and MAD2L1 in pathways related to splicing, bladder cancer, non-homologous end joining and homologous recombination, glycosaminoglycan biosynthesis chondroitin sulfate, progesterone-mediated oocyte maturation and mismatch repair. PASTAA database indicated the involvement of transcription factors such as Roralpha1, Pou6f1, Roralpha2, Atf-1, Pax-3, C/ebpalpha, Nkx2-1 in the regulation of CCNA2, while no transcription factors were predicted for MAD2L1..Immune infiltration analysis revealed a close association between ESCC and plasma cells, CD8 + T cells, monocytes, M0 macrophages, M1 macrophages, dendritic cells, and resting mast cells.Drug prediction for CCNA2 included 7 drugs such as ETHINYL ESTRADIOL, Seliciclib and TAMOXIFEN, while no drugs were predicted for MAD2L1.qRT-PCR and immunohistochemistry demonstrated high expression of CCNA2 in ESCC, while MAD2L1 showed no significant difference between ESCC and normal esophageal squamous epithelial tissues. CONCLUSION: CCNA2 and MAD2L1 may be potential biomarkers for ESCC, providing a novel basis for understanding the molecular mechanisms underlying ESCC pathogenesis.Additionally, the potential drugs predicted for CCNA2 may emerge as a new hope for ESCC patients in the future.

Humans↗

PubMed2025

Neoadjuvant palbociclib in women with operable, hormone receptor-positive breast cancer.

The addition of a cyclin-dependent kinase 4/6 (CDK4/6) inhibitor to endocrine therapy augments biological response in breast cancer. This phase III randomized, double-blind study evaluated the efficacy of adding palbociclib to neoadjuvant endocrine therapy (NET) for operable, hormone receptor-positive human epidermal growth factor receptor 2 (HER2)-negative breast cancer. Patients randomly received 16 weeks of endocrine therapy (letrozole for postmenopausal and tamoxifen plus ovarian function suppression for pre-/perimenopausal patients) plus palbociclib or placebo. The co-primary endpoints included preoperative endocrine prognostic index (PEPI) score and EndoPredict (EPclin) risk score according to the gatekeeping procedure. Of 141 randomized patients, 130 completed the treatment with surgical samples evaluable for endpoints in 126 patients. The proportion of patients with a low, moderate, and high PEPI score was 15.2, 50.0, and 34.8% in the palbociclib arm and 13.3, 55.0, and 31.7% in the placebo arm, respectively, with no statistical difference (one-sided P = 0.563). Statistical analysis was not performed on EPclin risk score. No new safety signals were reported. Permanent treatment discontinuation by adverse events was reported for seven (9.7%) and zero patients in the palbociclib and placebo arms, respectively. In conclusion, the addition of palbociclib to NET did not improve the efficacy. ClinicalTrials.gov NCT03969121.

Humans↗

PubMed2026

In vivo CRISPR screening links NFKB1 to endocrine resistance in ER+ breast cancer.

Resistance to endocrine therapy (ET) remains a major clinical challenge in the treatment of estrogen receptor-positive (ER+) breast cancer, underscoring the need for novel therapeutic targets. To identify genetic drivers of ET resistance, we conducted an in vivo genome-wide CRISPR-Cas9 screen in MCF7 cells implanted into ovariectomized nude mice under estrogen-deprived conditions. Despite the bottlenecks inherent to in vivo pooled screening, recurrent enrichment analysis identified NFKB1 as a candidate regulator of estrogen-independent tumor progression. Functional studies confirmed that NFKB1 deficiency enhanced tumorigenicity and conferred resistance to tamoxifen and fulvestrant both in vitro and in vivo. Mechanistically, transcriptomic and biochemical analyses revealed that NFKB1 deficiency activated canonical NF-κB signaling, leading to inflammatory gene induction and enhanced ER signaling. Furthermore, pharmacologic inhibition of NF-κB signaling restored ET sensitivity in NFKB1-deficient cells. Analysis of TCGA breast cancer datasets revealed reduced NFKB1 expression in luminal breast tumors, whereas expression of other NF-κB family members was largely unchanged. Further analysis showed that low NFKB1 expression was associated with poorer clinical outcomes in patients with ER+ breast cancer. Collectively, these findings identify NFKB1 as a negative regulator of NF-κB signaling and endocrine resistance in ER+ breast cancer and provide mechanistic evidence linking NF-κB activation to ligand-independent ER signaling. Our results support further investigation of NFKB1 as a candidate biomarker and of NF-κB pathway inhibition as a potential therapeutic strategy in endocrine therapy-resistant breast cancer. These findings also illustrate the utility of in vivo CRISPR screening for identifying candidate regulators of endocrine resistance in breast cancer.

ER+ breast cancer↗

PubMed2026

Monocarboxylate Transporter 2 (MCT2) Reduction Is Associated with Increased Lung Tumor Growth and Alterations in the Immune Microenvironment in a Subcutaneous Tumor Model.

Monocarboxylate transporter 2 (MCT2; SLC16A7) is a high-affinity pyruvate transporter implicated in cancer metabolism. However, its role in lung cancer progression and the tumor microenvironment remains unclear. This study examined the effects of MCT2 reduction on tumor growth and cell-type-specific transcriptional changes within the tumor microenvironment. MCT2 loxP/loxP mice were crossed with mCre-Tg mice, and MCT2 deletion was induced by tamoxifen. Control (CO) mice received vehicle treatment. TC1 cells (100,000 cells/mouse) were injected subcutaneously, and tumors were harvested after 24 days. Single-nucleus RNA sequencing (snRNA-seq) was performed on isolated tumor nuclei (4000 nuclei/sample; n = 3 per group) using the 10x Genomics Chromium platform. Data were processed with Cell Ranger v3.0.2 and Seurat v5.2.1, followed by differential expression and pathway enrichment analyses integrated with macrophage bulk RNA-seq data. Tumors in mice with systemic MCT2 reduction grew significantly faster than those in control mice, demonstrating an association between host MCT2 reduction and increased tumor growth. Transcriptomic analysis generated high-quality profiles from 6864 CO and 10,055 KO nuclei. Clustering identified 12 cellular populations and cell types. MCT2 reduction altered pathways involved in glycolysis, the tricarboxylic acid cycle, oxidative phosphorylation, and fatty acid metabolism across multiple populations. Macrophages showed prominent transcriptional changes, including enrichment of MAPK, PI3K-Akt, IgSF-CAM, ECM, and cytokine-cytokine signaling pathways. These findings were supported by macrophage bulk RNA-seq data. Systemic MCT2 reduction was associated with increased tumor growth and broad transcriptional alterations within the tumor micro-environment. Differences in metabolic and immune-related transcriptional programs, particularly in macrophages, identify potential mechanisms associated with tumor progression that warrant further functional investigation.

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