Deleted in liver cancer 1 suppresses the growth of prostate cancer cells through inhibiting Rho-associated protein kinase pathway

OBJECTIVE: Deleted in liver cancer 1 (DLC1) is a GTPase-activating protein that is reported as a suppressor in certain human cancers. However, the detailed biological function of DLC1 is still unclear in human prostate cancer (PCa). In the present study, we aimed to explore the function of DLC1 in PCa cells. METHODS: Silencing and overexpression of DLC1 were induced in an androgen-sensitive PCa cell line (LNCaP) using RNA interference and lentiviral vector transduction. The Cell Counting Kit-8 assay was performed to determine cell proliferation. The cell cycle was examined by performing a propidium iodide staining assay. RESULTS: Our results indicated that DLC1 overexpression markedly suppressed the proliferation and cell cycle progression of LNCaP cells. Moreover, DLC1 expression was negatively correlated with Rho-associated protein kinase (ROCK) expression in LNCaP cells. Importantly, this study showed that the ROCK inhibitor Y27632 restored the function of DLC1 in LNCaP cells and reduced the tumorigenicity of LNCaP cells in vivo. CONCLUSION: Our results indicated that DLC1 overexpression markedly suppressed the proliferation and cell cycle progression of PCa cells and negatively correlated with ROCK expression in PCa cells and tissue.