GEOapplication/xmlftp://ftp.ncbi.nlm.nih.gov/geo/series/GSE303nnn/GSE303244/primaryOK200TranscriptomicsHomo sapiensExpression profiling by high throughput sequencinghttps://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE303244GEOGSEfalseThe PARP Inhibitor Talazoparib efficiently Suppresses Tumor Growth in Castration-Resistant Prostate CancerTo address the limited understanding of PARP inhibitor monotherapy in castration-resistant prostate cancer (CRPC), we investigated the antitumor effects of Talazoparib in CRPC cells with homologous recombination repair (HRR) gene mutations. We treated DU 145 and PC-3 cells with Talazoparib and observed reduced proliferation, migration, and colony formation. Western blot analysis showed increased apoptosis and DNA damage. RNA sequencing revealed downregulation of key HRR genes (BRCA1/2, ATM, ATR), and gene set enrichment analysis confirmed suppression of DNA repair pathways and activation of immune-related responses. These findings suggest that Talazoparib not only exploits synthetic lethality but also impairs HRR gene expression, supporting its potential as monotherapy in HRR-deficient CRPC.2026/07/31GSE303244GSM9121683GSM9121685GSM9121684GSM9121687GSM9121686GSM912168824676303244Homo sapiens