Identification of castration-dependent and -independent driver genes and pathways in castration-resistant prostate cancer (CRPC)

Background Prostate cancer (PCa) is one of the most diagnosed cancers in the world. PCa inevitably progresses to castration-resistant prostate cancer (CRPC) after androgen deprivation therapy treatment, and castration-resistant state means a shorter survival time than other causes. Here we aimed to define castration-dependent and -independent diver genes and molecular pathways in CRPC which are responsible for such lethal metastatic events. Methods By employing digital gene expression (DGE) profiling, the alterations of the epididymal gene expression profile in the mature and bilateral castrated rat were explored. Then we detect and characterize the castration-dependent and -independent genes and pathways with two data set of CPRC-associated gene expression profiles publicly available on the NCBI. Results We identified 1,632 up-regulated and 816 down-regulated genes in rat's epididymis after bilateral castration. Differential expression analysis of CRPC samples compared with the primary PCa samples was also done. In contrast to castration, we identified 97 up-regulated genes and 128 down-regulated genes that changed in both GEO dataset and DGE profile, and 120 up-regulated genes and 136 down-regulated genes changed only in CRPC, considered as CRPC-specific genes independent of castration. CRPC-specific DEGs were mainly enriched in cell proliferation, while CRPC-castration genes were associated with prostate gland development. NUSAP1 and NCAPG were identified as key genes, which might be promising biomarkers of the diagnosis and prognosis of CRPC. Conclusion Our study will provide insights into gene regulation of CRPC dependent or independent of castration and will improve understandings of CRPC development and progression.

Automated summary

In this study, alterations in gene expression profiles in rat's epididymis after bilateral castration were identified, as well as castration-dependent and -independent genes and pathways in CRPC using publicly available gene expression profiles. Key genes NUSAP1 and NCAPG were proposed as potential biomarkers for the diagnosis and prognosis of CRPC. This research provides insights into gene regulation in CRPC development and progression.