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bioRxiv · 10.1101/2025.09.14.676113

BRCA2-deficiency Causes Global Transcriptomic Alterations in Endothelial Cells

Nikfarjam, S.·Singh, A.·Bu, S.·Nguyen, H. C.·Singh, K. K.
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Abstract

This study aims to explore the alterations in gene expression following BRCA2 loss in endothelial cells and to investigate the potential contribution of BRCA2 in regulating the endothelial protein-coding transcriptome. Cultured human umbilical vein endothelial cells (HUVECs) were transfected with siBRCA2 or non-targeting scrambled RNA as control. Total RNA was extracted and used for RNA sequencing following purification and quality check. Transcription profiles and differentially expressed genes (DEGs) were identified. Enrichment of functions and signaling pathways analysis were performed based on Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. In total, 3196 DEGs with (cut-off 1.5-fold) were identified, of which 1852 genes were upregulated, and 1344 genes were downregulated in BRCA2-deficient HUVECs. Cell cycle exit and neuronal differentiation 1 (CEND1) and mannose receptor C-type 1 (MRC1) were the most significantly up- and downregulated genes, respectively, in BRCA2-deficient endothelial cells. The expression of top DEGs were further validated by RT-qPCR in HUVECs and in human coronary artery endothelial cells. The GO and KEGG analysis suggest that cell adhesion molecules and cytokine-cytokine receptor interaction may play an important role in BRCA2-deficient endothelial cells. Overall, these findings contribute to a greater understanding of the mechanisms involved in BRCA2-mediated endothelial function.

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Nikfarjam, S., Singh, A., Bu, S., Nguyen, H. C., Singh, K. K.. 2025-09-17. BRCA2-deficiency Causes Global Transcriptomic Alterations in Endothelial Cells. https://doi.org/10.1101/2025.09.14.676113

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