Biology subjects

Rubin, M.

Publications and source records attributed to Rubin, M..

11 recordsLinked to original sources

bioRxiv2026

Log-linear scaling of TRPV4-KCNN4 transcripts tunes ROCK-dependent mechanotransduction in a DCIS progression model

Mechanotransduction converts mechanical stress into cellular responses, yet how transcript abundance sets mechanotransduction capacity remains unclear. Using an isogenic MCF10A breast epithelial progression series in which crowding functionally inhibits plasma-membrane TRPV4 and triggers pro-invasive motility, we quantified how pathway mRNA levels relate to stress-evoked single-cell motility. TRPV4 (Ca{superscript 2}-permeable mechanosensor) and KCNN4 (Ca{superscript 2}-activated K channel) mRNA levels scaled log-linearly with motility under hyperosmotic stress or pharmacologic TRPV4 inhibition (both engaging the crowding-induced pro-invasive motility program) across a [~]600-fold TRPV4 mRNA range including isogenic and patient-derived DCIS lines (TRPV4: R{superscript 2}=0.89-0.92; KCNN4: R{superscript 2}=0.81-0.94). In contrast, bulk TRPV4 protein did not correlate with motility. Mechanistically, ROCK inhibition abolished stress-induced cortical actin-myosin organization and associated motility gains, identifying ROCK-dependent cortical contractility as a downstream effector. Notably, log-linear scaling was restricted to membrane channels and did not extend to tested cytosolic effectors, suggesting hierarchical transcript regulation may shape heterogeneous DCIS stress responsiveness in this model system.

cell biology↗

bioRxiv2026

Aurora kinase A is a synthetic lethal target in FANCA-deficient cancers

Loss-of-function genomic alterations in FANCA occur across multiple cancer types, yet no molecularly tailored therapies have successfully exploited this potential vulnerability. Using complementary unbiased approaches, including a genome-wide CRISPR/Cas9 loss-of-function screen and a high-throughput drug screen in isogenic cancer cell-based models, we identified Aurora kinase A (AURKA) as a reproducible synthetic lethal target of FANCA-deficient cancers. Inhibition of AURKA induced chromosomal instability, micronucleation, and early G2/M arrest selectively in FANCA-deficient cells, consistent with an increased reliance on mitotic checkpoint control. Mechanistically, FANCA deficiency is associated with an elevated AURKA expression at both the transcriptomic and protein levels, and with an upregulation of mitotic spindle and G2/M checkpoint gene signatures. Analysis of large-scale cancer genomics datasets, including over 650,000 clinically sequenced tumors, confirms that FANCA is the most frequently altered Fanconi anemia pathway gene across cancers, and that Fanconi anemia-defective tumors exhibit an increased tumor mutational burden and genomic instability. Collectively, our findings point to AURKA inhibition as a promising precision treatment strategy in FANCA-deficient cancers and provide a rationale to further explore this strategy in the clinic.

cancer biology↗

bioRxiv2025

Blocking Minor Intron Splicing Disrupts DNA Repair and Overcomes Therapy Resistance in Prostate and Breast Cancer

The minor spliceosome (MiS) is a specialized RNA-processing machinery upregulated in cancer, promoting oncogene expression. We uncovered an adaptive resistance mechanism driven by secretion of extracellular vesicles enriched in U6atac snRNA, which amplifies MiS activity and promotes therapy resistance. Here, we show that U6atac snRNA, a crucial MiS component, reverses this process when depleted, revealing it as a druggable vulnerability in therapy-resistant prostate and breast cancers. U6atac knockdown triggers R-loop-mediated DNA damage while impairing repair by downregulating key DNA repair factors, disabling both homologous recombination and non-homologous end joining. This dual effect sensitizes prostate and breast tumors to PARP inhibitors, cisplatin, and radiation, independent of BRCA status. Across multiple in vitro and in vivo models, MiS targeting demonstrates tumor-selective activity with minimal toxicity. These findings position U6atac as a central regulator of genome stability and establish MiS targeting as a promising approach to potentiate genotoxic therapy and overcome resistance. Statement of significanceU6atac, a minor spliceosome component, is a crucial regulator of genome stability in cancer. Its knockdown triggers R-loop-driven DNA damage, downregulates DNA repair genes, and sensitizes tumors to DNA-damaging therapies while simultaneously blocking resistance mechanisms. Thus, minor spliceosome knockdown is a tumour-selective and broadly applicable therapeutic strategy.

cancer biology↗

bioRxiv2024

A forward genetic screen identifies Sirtuin1 as a driver of neuroendocrine prostate cancer

Although localized prostate cancer is relatively indolent, advanced prostate cancer manifests with aggressive and often lethal variants, including neuroendocrine prostate cancer (NEPC). To identify drivers of aggressive prostate cancer, we leveraged Sleeping Beauty (SB) transposon mutagenesis in a mouse model based on prostate-specific loss-of-function of Pten and Tp53. Compared with control mice, SB mice developed more aggressive prostate tumors, with increased incidence of metastasis. Notably, a significant percentage of the SB prostate tumors display NEPC phenotypes, and the transcriptomic features of these SB mouse tumors recapitulated those of human NEPC. We identified common SB transposon insertion sites (CIS) and prioritized associated CIS-genes differentially expressed in NEPC versus non-NEPC SB tumors. Integrated analysis of CIS-genes encoding for proteins representing upstream, post-translational modulators of master regulators controlling the transcriptional state of SB-mouse and human NEPC tumors identified sirtuin 1 (Sirt1) as a candidate mechanistic determinant of NEPC. Gain-of-function studies in human prostate cancer cell lines confirmed that SIRT1 promotes NEPC, while its loss-of-function or pharmacological inhibition abrogates NEPC. This integrative analysis is generalizable and can be used to identify novel cancer drivers for other malignancies. SummaryUsing an unbiased forward mutagenesis screen in an autochthonous mouse model, we have investigated mechanistic determinants of aggressive prostate cancer. SIRT1 emerged as a key regulator of neuroendocrine prostate cancer differentiation and a potential target for therapeutic intervention.

cancer biology↗

bioRxiv2022

PipeIT2: A tumor-only somatic variant calling workflow for Molecular Diagnostic Ion Torrent sequencing data

Precision oncology relies on the accurate identification of somatic mutations in cancer patients. While the sequencing of the tumoral tissue is frequently part of routine clinical care, the healthy counterparts are rarely sequenced. We previously published PipeIT, a somatic variant calling workflow specific for Ion Torrent sequencing data enclosed in a Singularity container. PipeIT combines user-friendly execution, reproducibility and reliable mutation identification, but relies on matched germline sequencing data to exclude germline variants. Expanding on the original PipeIT, here we describe PipeIT2 to address the clinical need to define somatic mutations in the absence of germline control. We show that PipeIT2 achieves a >95% recall for variants with variant allele fraction >10%, reliably detects driver and actionable mutations and filters out most of the germline mutations and sequencing artifacts. With its performance, reproducibility and ease of execution, PipeIT2 is a valuable addition to molecular diagnostics laboratories.

bioinformatics↗

bioRxiv2022

Capped nascent RNA sequencing reveals novel therapy-responsive enhancers in prostate cancer

Mounting evidence suggests that enhancer RNA (eRNA) transcription start sites (TSSs) provide higher sensitivity and specificity for enhancer identification than histone modifications and chromatin accessibility. The extent to which changes in eRNA transcription correspond to changes in enhancer activity, however, remains unclear. Here, we used precision run-on and capped RNA sequencing (PRO-cap) to assess changes in enhancer activity in response to treatment with the androgen receptor signaling inhibitor, enzalutamide (ENZ). We identified 6,189 high-confidence candidate enhancers in the human prostate cancer cell line, LNCaP; 853 of which demonstrated significant changes in activity in response to drug treatment. Notably, we found that 67% and 54% of drug-responsive enhancers did not show similar changes in activity in previous studies that utilized ChIP-seq and ATAC-seq, respectively. Strikingly, 79% of regions with increased eRNA transcription showed no other biochemical alterations, implying that PRO-cap can capture a set of precise changes in enhancer activity that classical approaches lack the sensitivity to detect. We performed in vivo functional validations of candidate enhancers and found that CRISPRi targeting of PRO-cap-specific drug-responsive enhancers impaired ENZ regulation of downstream target genes, suggesting that changes in eRNA TSSs mark true biological changes in enhancer activity with high sensitivity. Our study highlights the utility of using PRO-cap as a complementary approach to canonical biochemical methods for detecting precise changes in enhancer activity and, in particular, for better understanding disease progression and responses to treatment.

genomics↗

bioRxiv2021

Harbingers of Aggressive Prostate Cancer: Precision Oncology Case Studies

Primary prostate cancer (PCa) can show marked molecular heterogeneity. However, systematic analyses comparing primary PCa and matched metastases in individual patients are lacking. We aimed to address the molecular aspects of metastatic progression while accounting for heterogeneity of primary PCa. In this pilot study, we collected 12 radical prostatectomy (RP) specimens from men who subsequently developed metastatic castration-resistant prostate cancer (mCRPC). We used histomorphology (Gleason grade, focus size, stage) and immunohistochemistry (IHC) (ERG and p53) to identify independent tumors and/or distinct subclones of primary PCa. We then compared molecular profiles of these primary PCa areas to matched metastatic samples using whole exome sequencing (WES) and amplicon-based DNA and RNA sequencing. Based on combined pathology and molecular analysis, seven (58%) RP specimens harbored monoclonal and topographically continuous disease, albeit with some degree of intra-tumor heterogeneity; four (33%) specimens showed true multifocal disease; and one displayed monoclonal disease with discontinuous topography. Early (truncal) events in primary PCa included SPOP p.F133V (one patient), BRAF p.K601E (one patient), and TMPRSS2:ETS rearrangements (nine patients). Activating AR alterations were seen in eight (67%) mCRPC patients, but not in matched primary PCa. Hotspot TP53 mutations, found in metastases from three patients, were readily present in matched primary disease. Alterations in genes encoding epigenetic modifiers were observed in several patients (either shared between primary foci and metastases or in metastatic samples only). WES-based phylogenetic reconstruction and/or clonality scores were consistent with the index focus designated by pathology review in six out of nine (67%) cases. The three instances of discordance pertained to monoclonal, topographically continuous tumors, which would have been considered as unique disease in routine practice. Overall, our results emphasize pathologic and molecular heterogeneity of primary PCa, and suggest that comprehensive IHC-assisted pathology review and genomic analysis are highly concordant in nominating the "index" primary PCa area.

cancer biology↗

bioRxiv2021

Development of a transboundary model of livestock disease in Europe

Epidemiological models of notifiable livestock disease are typically framed at a national level and targeted for specific diseases. There are inherent difficulties in extending models beyond national borders as details of the livestock population, production systems and marketing systems of neighbouring countries are not always readily available. It can also be a challenge to capture heterogeneities in production systems, control policies, and response resourcing across multiple countries, in a single transboundary model. In this paper we describe EuFMDiS, a continental-scale modelling framework for transboundary animal disease, specifically designed to support emergency animal disease planning in Europe. EuFMDiS simulates the spread of livestock disease within and between countries and allows control policies to be enacted and resourced on per-country basis. It provides a sophisticated decision support tool that can be used to look at the risk of disease introduction, establishment and spread; control approaches in terms of effectiveness and costs; resource management; and post-outbreak management issues.

bioinformatics↗

bioRxiv2020

Role of Specialized mSWI/SNF Complexes in Prostate Cancer Lineage Plasticity

Advanced prostate cancer initially responds to hormonal treatment, but ultimately becomes resistant and requires more potent therapies. One mechanism of resistance observed in [~]10% of these patients is through lineage plasticity, which manifests in a partial or complete small cell or neuroendocrine prostate cancer (NEPC) phenotype. Here, we investigate the role of the mammalian SWI/SNF (mSWI/SNF) chromatin remodeling complex in NEPC. Using large patient datasets, patient-derived organoids and cancer cell lines, we identify mSWI/SNF subunits that are deregulated in NEPC and demonstrate that SMARCA4 (BRG1) overexpression is associated with aggressive disease. We also show that SWI/SNF complexes interact with different lineage-specific factors in NEPC compared to prostate adenocarcinoma. These data suggest a role for mSWI/SNF complexes in therapy-related lineage plasticity, which may be relevant for other solid tumors.

cancer biology↗

bioRxiv2019

Integrative genomic, transcriptomic, and epigenomic analyses of benign prostatic hyperplasia reveal new options for therapy

Benign prostatic hyperplasia (BPH), a nonmalignant enlargement of the prostate, is one of the most common diseases affecting aging men, but the underlying molecular features of BPH remain poorly understood, and therapeutic options are limited. Here we employed a comprehensive molecular investigation of BPH, including genomic, transcriptomic and epigenetic profiling of 18 BPH cases. At the molecular level, we found no evidence of neoplastic features in BPH: no evidence of driver genomic alterations, including low coding mutation rates, mutational signatures consistent with aging tissues, minimal copy number alterations, and no genomic rearrangements. Similarly at the epigenetic level, we found global hypermethylation was the dominant process (unlike most neoplastic processes). By integrating transcriptional and methylation signatures, we identified two BPH subgroups with distinct clinical features and associated signaling pathways, which were validated in two independent cohorts. Finally, our analyses nominated mTOR inhibitors as a potential subtype-specific therapeutic option. Supporting this, a cohort of men exposed to mTOR inhibitors showed a significant decrease in prostate size. Our results demonstrate that BPH consists of distinct molecular subgroups, with potential for subtype-specific precision therapy via mTOR inhibition.

genomics↗

bioRxiv2018

GRAM: A generalized model to predict the molecular effect of a non-coding variant in a cell-type specific manner

There has been much effort to prioritize genomic variants with respect to their impact on \"function\". However, function is often not precisely defined: Sometimes, it is the disease association of a variant; other times, it reflects a molecular effect on transcription or epigenetics. Here we coupled multiple genomic predictors to build GRAM, a generalized model, to predict a well-defined experimental target: the expression-modulating effect of a non-coding variant in a cell-specific manner. As a first step, we performed feature engineering: using a LASSO regularized linear model, we found transcription factor (TF) binding most predictive, especially for TFs that are hubs in the regulatory network; in contrast, evolutionary conservation, a popular feature in many other functional-impact predictors, has almost no contribution. Moreover, TF binding inferred from in vitro SELEX is as effective as that from in vivo ChIP-Seq. Second, we implemented GRAM integrating SELEX features and expression profiles. The program combines a universal regulatory score for a variant in a non-coding element with a modifier score reflecting the particular cell type. We benchmarked GRAM on a large-scale MPRA dataset in the GM12878 cell line, achieving a ROC score of [~]0.73; performance on the K562 cell line was similar. Finally, we evaluated the performance of GRAM on targeted regions using luciferase assays in MCF7 and K562 cell lines. We noted that changing the insertion position of the construct relative to the reporter gene gives very different results, highlighting the importance of carefully defining the functional target the model is predicting.\n\nAuthor SummaryNoncoding variants lie outside of protein-coding regions, and are found to have disease associations. However, knowledge on the molecular effect of these non-coding variants in a cell-specific context is very limited. Also, different output between multiple experiment platforms may introduce extra complexity in analyzing the molecular function of these variants. We developed GRAM, a generalized model to predict molecular effect of non-coding variants in multiple cell types for different experimental platforms. We first selected the most informative cell-independent SELEX transcription factor binding score on the variant locus as features and then combine cell-specific gene expression profile to build a multi-step prediction model. GRAM has been successfully tested on both MPRA and Luciferase assay, and on three different cell lines: GM12878, K562 and MCF7, shows high performance.

bioinformatics↗