Biology subjects

Adkar, S.

Publications and source records attributed to Adkar, S..

3 recordsLinked to original sources

bioRxiv2026

Cancer drives atherosclerotic plaque vulnerability by inducing pathological angiogenesis

Cardiovascular disease (CVD) is the leading cause of death for many cancer survivors, a phenomenon traditionally attributed to shared risk factors and cardiotoxic chemotherapies. Here, we hypothesized that cancer may also directly promote atherosclerosis. Propensity-matched analyses confirmed significantly elevated cardiovascular event rates amongst cancer patients, independent of comorbidities such as smoking. Atheroprone mice implanted with colorectal tumors demonstrated accelerated features of plaque vulnerability, driven by pathological angiogenesis and intraplaque hemorrhage. Mechanistically, tumor-secreted TNF- induced the pro-angiogenic factor LRG1 across multiple murine models and human plaques. Therapeutic interventions targeting these pathways, including with FDA-approved cytokine inhibitors or tumor resection, prevented plaque destabilization in mice and reduced coronary revascularization rates in patients. Together, these findings suggest that cancer may causally promote CVD and unveil novel translational strategies for cancer survivors.

pathology↗

bioRxiv2024

BST2 induces vascular smooth muscle cell plasticity and phenotype switching during cancer progression

BackgroundSmooth muscle cell (SMC) plasticity and phenotypic switching play prominent roles in the pathogenesis of multiple diseases, but their role in tumorigenesis is unknown. We investigated whether and how SMC diversity and plasticity plays a role in tumor angiogenesis and the tumor microenvironment. Methods and ResultsWe use SMC-specific lineage-tracing mouse models and single cell RNA sequencing to observe the phenotypic diversity of SMCs participating in tumor vascularization. We find that a significant proportion of SMCs adopt a phenotype traditionally associated with macrophage-like cells. These cells are transcriptionally similar to resolution phase M2b macrophages, which have been described to have a role in inflammation resolution. Computationally predicted by the ligand-receptor algorithm CellChat, signaling from BST2 on the surface of tumor cells to PIRA2 on SMCs promote this phenotypic transition; in vitro SMC assays demonstrate upregulation of macrophage transcriptional programs, and increased proliferation, migration, and phagocytic ability when exposed to BST2. Knockdown of BST2 in the tumor significantly decreases the transition towards a macrophage-like phenotype, and cells that do transition have a comparatively higher inflammatory signal typically associated with anti-tumor effect. ConclusionAs BST2 is known to be a poor prognostic marker in multiple cancers where it is associated with an M2 macrophage-skewed TME, these studies suggest that phenotypically switched SMCs may have a previously unidentified role in this immunosuppressive milieu. Further translational work is needed to understand how this phenotypic switch could influence the response to anti-cancer agents and if targeted inhibition of SMC plasticity would be therapeutically beneficial.

cancer biology↗

bioRxiv2021

Genome-wide annotation of gene regulatory elements linked to cell fitness

Noncoding regulatory elements control gene expression and thus govern nearly all biological processes. Epigenomic profiling assays have identified millions of putative regulatory elements, but systematically determining the function of those regulatory elements remains a substantial challenge. Here we adapt CRISPR screening by epigenetic repression to screen all 111,619 putative non-coding regulatory elements defined by open chromatin sites in human K562 leukemia cells for their role in regulating essential cellular processes and proliferation. In an initial screen containing 1,084,704 gRNAs, we implemented an analysis framework to quantify perturbation effects, and nominate 1,108 regulatory elements that strongly impact cell fitness. We tested 8,845 of the primary screen elements in a secondary screen, evaluated their cell-type specificity in a second cancer cell line, and then used a single-cell RNA-seq CRISPR screen to discover 63 connections between distal regulatory elements and target genes. This comprehensive and quantitative genome-wide map of essential gene regulatory elements presents a framework for extensive characterization of noncoding regulatory elements that drive complex cell phenotypes and for prioritizing non-coding genetic variants that may contribute to common traits and disease risk.

genomics↗