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Jit, S.

Publications and source records attributed to Jit, S..

4 recordsLinked to original sources

Systematic Meta-Analysis of Published Transcriptomic Prognostic Signatures and Development of a Robust Multi-Cohort Prognostic Classifier for Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) exhibits pronounced molecular heterogeneity, yet the majority of published transcriptomic prognostic signatures suffer from limited reproducibility and have not achieved clinical translation. We systematically benchmarked 62 published TNBC prognostic signatures across 6 independent cohorts (n=1,357) using a unified analytical framework spanning multiple scoring algorithms, survival endpoints, and threshold strategies. While 17 signatures demonstrated consistent univariate prognostic associations, only 4 remained independently prognostic after adjustment for clinicopathological variables, and none achieved robustness across all analytical conditions-underscoring the fragility of existing classifiers. Leveraging genes with concordant survival associations across all 6 discovery cohorts, we identified a reproducible 15-gene directionally concordant gene set (DCGS) signature and distilled it into MetaSig-EFS, a 13-gene prognostic model optimized using a cohort-aware DeepSurv framework. MetaSig-EFS demonstrated robust cross-cohort generalizability, achieving validation concordance indices of 0.89 in GSE19615 and 0.69 in JBordet, with corresponding 3- and 5-year time-dependent AUROCs of 0.89 and 0.96 in GSE19615 and 0.80 and 0.71 in JBordet, respectively, while retaining independent prognostic value across established TNBC molecular sub-typing systems. Leveraging the TAHOE-100M transcriptomic perturbation atlas, we systematically prioritized candidate therapeutics through large-scale drug repurposing, identifying Paclitaxel as the top-ranked compound, followed by Venetoclax and Tucatinib. Together, these findings provide biologically informed and clinically actionable therapeutic hypotheses that extend the translational utility of our validated prognostic framework for TNBC risk stratification.

cancer biology↗

Macrophage Cholesterol Homeostasis Underpins the role of Sertraline as an Adjunctive Agent in Tuberculosis Therapy.

Cellular metabolism plays a deterministic role in the macrophage responses to intracellular pathogens such as Mycobacterium tuberculosis (Mtb) and infection control. Here, we demonstrate that the significant rewiring of the macrophage cholesterol metabolism by sertraline (SRT), an FDA-approved antidepressant, effectively enhances bacterial control. SRT, by virtue of its potent cationic amphiphilicity leads to the accumulation of lysosomal cholesterol in macrophages and activating the transcription factor SREBP2 and enhancing cholesterol biosynthesis. By specific gene silencing and biochemical inhibition assays, we further demonstrate that this metabolic reprogramming promotes lysosomal membrane permeabilization, mitochondrial reactive oxygen species (ROS) generation, heightened IL-1{beta} release, collectively enhancing macrophage bactericidal activity. Our results thus highlight a previously underappreciated link between cholesterol homeostasis and inflammasome activation, which contributes to improved Mtb clearance in the presence of adjunctive sertraline therapy. Statement of significanceTuberculosis remains a leading cause of global mortality, and treatment success is limited due to a long treatment regimen. This study identifies macrophage cholesterol homeostasis as a central pathway to enhance anti-tubercular therapy. We show that Sertraline, an FDA-approved antidepressant, a cationic amphiphilic drug (CAD), reprograms cholesterol trafficking through NPC1 inhibition. This drives the consequential processing of the master regulator SREBP2, accompanied by lysosomal membrane permeabilization. Collectively, these lead to mitochondrial ROS production and activation of NLRP3 signalling, boosting inflammasome-mediated bacterial clearance. By establishing cholesterol sequestration as the mechanistic basis of host-directed activity of sertraline and distinguishing it from ineffective CADs, our work provides a mechanistic framework for developing cholesterol-modulating host-directed adjuncts to improve TB treatment outcomes. Graphical abstract: SRT induced lysosomal cholesterol accumulation results in enhanced bacterial control via inflammasome activation O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=101 SRC="FIGDIR/small/665474v3_ufig1.gif" ALT="Figure 1"> View larger version (34K): org.highwire.dtl.DTLVardef@1019b4dorg.highwire.dtl.DTLVardef@7b0ae8org.highwire.dtl.DTLVardef@9297eorg.highwire.dtl.DTLVardef@1832bef_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

Alternative Promoters Drive Transcriptomic Reprogramming and Prognostic Stratification in TNBC

Transcriptional regulation frequently involves alternative promoters, yet the distinct regulatory mechanisms governing alternative versus reference promoters remain poorly understood in Triple-Negative Breast Cancer (TNBC), a high-risk breast tumor subtype. It is worth emphasizing that, despite the availability of extensive short-read sequencing data, the impact of alternative promoter usage on TNBC transcriptome dynamics and patient survival remains underexplored. The current study leverages RNA sequencing data from the publicly available TNBC tumor samples (360) and adjacent normal samples (88) to identify TNBC-specific and subtype-specific active alternative promoters (AAPs). To further validate these findings, we integrated H3K4me3 ChIP-seq data, confirming key promoter switching events. We found that HDAC9, RPS14, and EPN1 exhibit tumor-specific AAP expression, while AKAP9 and SEC31A show basal subtype-specific promoter activity in TNBC. Beyond their transcriptional impact, we also explored the prognostic significance of AAPs. The alternative promoters of HUWE1 and FTX were recognized as independent survival predictors in TNBC. Notably, multivariate analysis demonstrated that prognostic AAPs remained significant in predicting relapse-free survival (RFS) even after adjusting for copy number alterations (CNA) and mRNA-based subtypes. Our AAP-based prognostic model achieved C-index of 0.73 in training and 0.72 in validation, with AUROC of 0.72 and integrated Brier score of 0.09 in validation dataset. Our findings indicate that AAP activity serves as a crucial prognostic marker beyond traditional clinical parameters, enhancing patient stratification and risk assessment in TNBC. Understanding promoter switching events may further unveil novel therapeutic targets, paving the way for precision oncology strategies in highly aggressive breast tumors.

genomics↗

Novel tumorigenic FOXM1-PTAFR-PTAF axis revealed by multi-omic profiling in TP53/CDKN2A-double knockout human gastroesophageal junction organoid model

Inactivation of the tumor suppressor genes TP53 and CDKN2A occurs early during gastroesophageal junction (GEJ) tumorigenesis. However, due to a paucity of GEJ-specific disease models, cancer-promoting consequences of TP53 and CDKN2A inactivation at the GEJ have been incompletely characterized. Here we report the development of the first wild-type primary human GEJ organoid model, as well as a CRISPR-edited transformed GEJ organoid model. CRISPR/Cas9 engineering to inactivate TP53 and CDKN2A (TP53/CDKN2AKO) in GEJ organoids induced morphologic dysplasia as well as pro-neoplastic features in vitro and tumor formation in vivo. Notably, lipidomic profiling identified several Platelet-Activating Factors (PTAFs) among the most upregulated lipids in CRISPR-edited organoids; and importantly, PTAF/PTAFR abrogation by siRNA knockdown or a pharmacologic inhibitor (WEB2086) significantly blocked proliferation and other pro-neoplastic features of TP53/CDKN2AKO GEJ organoids in vitro and tumor formation in vivo. In addition, murine xenografts derived from Eso26, an established esophageal adenocarcinoma (EAC) cell line, were suppressed by WEB2086. Mechanistically, TP53/CDKN2A dual inactivation disrupted both the transcriptome and the DNA methylome, likely mediated by key transcription factors, particularly Forkhead Box M1 (FOXM1). Importantly, FOXM1 activated PTAFR transcription by binding to the PTAFR promoter, further amplifying the PTAF-PTAFR pathway. In summary, we established a robust model system for investigating early GEJ neoplastic events, identified crucial metabolic and epigenomic changes occurring during GEJ model tumorigenesis, and discovered a potential cancer-therapeutic strategy, while providing insights into pro-neoplastic mechanisms associated with TP53/CDKN2A inactivation in early GEJ neoplasia. One Sentence SummaryNovel tumorigenic FOXM1-PTAFR-PTAF axis revealed by multi-omic profiling in TP53/CDKN2A-double knockout human gastroesophageal junction organoid model. Graphic Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=172 SRC="FIGDIR/small/491356v1_ufig1.gif" ALT="Figure 1"> View larger version (27K): org.highwire.dtl.DTLVardef@18dcb8dorg.highwire.dtl.DTLVardef@2ec0d6org.highwire.dtl.DTLVardef@17622b8org.highwire.dtl.DTLVardef@e184bc_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗