Characterization of a centrosme loss - induced tumorigenic signature in prostate epithelial cells

Unlike many cancers, prostate cacner (PCa) lacks hallmark mutations in key oncogenes and tumor-suppressorgenes. Instead, PCa exhibit extensive genomic rearrangements and chromosomal instability (CIN). Previously, we found that cell within early-grade human primary prostate adenocarcinomas (PRAD) frequently lack centrosomes, and this frequency correlates with tumor grade. We demonstrated that transient removal of centrosomes within non-tumorigenic human prostate epithelial cells (hPrEC) induces CIN and was, strikingly, sufficient to transform subpopulations of cells capable of producing xenograft tumors in mice. To unravel the molecular mechanisms underlying this path to tumorigenesis, we isolated RNA from parental hPrECs, clonal lines subjected to transient centrosome loss, and xenograft tumor cells and performed bulk RNA-seq. This allowed us to characterize the transcriptomic profile induced by centrosome loss. To induce centrosome loss in prostate epithelial cells, we applied the PLK4 inhibitor centrinone to PrEC Hahn parental cells for 15 days, followed by monoclonal expansion in normal culture media without centronone. We selected lines with elevated levels of MYC and ERG and xenografted them into male NSG mice. Among all the lines injected into NSG mice, CN9 exhibited the highest tumorigenicity level, with 9 out of 12 injection sites forming tumors. Xenograft tumors derived from CN9 were then collected and cultured on petri dishes. Subsequently, we performed gene expression profiling analysis using RNA-seq data from parental cells (PrEC Hahn cells), centrosome loss clone (CN9), and xenograft tumor cells (CN1_1, CN1_2, CN2_2).