MicroRNA‑122 downregulates Rho‑associated protein kinase 2 expression and inhibits the proliferation of prostate carcinoma cells.

Abstract

MicroRNA‑122 (miR‑122) has been reported to be involved in the pathogenesis of several types of malignancies; however, its role in prostate carcinoma remains unknown. Thus, the current study aimed to investigate the functionality of miR‑122 in prostate carcinoma. Clinical data of 54patients with prostate carcinoma who were diagnosed and treated in Union Hospital (Wuhan, China) between January 2011 and January 2013 were retrospectively analyzed. The expression levels of miR‑122 and Rho‑associated protein kinase 2 (ROCK2) in prostate tumor and adjacent healthy tissues of patients, as well as in the serum of prostate carcinoma patients and healthy controls, were detected by reverse transcription‑quantitative polymerase chain reaction. Receiver operating characteristic curve and survival curve analyses were used to examine the diagnostic and prognostic values of serum miR‑122 for prostate carcinoma. In addition, miR‑122 mimic was transfected into prostate carcinoma cells, and the effects on cell proliferation and ROCK2 expression were explored by Cell Counting Kit‑8 and western blot assays, respectively. It was observed that miR‑122 was downregulated and ROCK2 was upregulated in tumor tissues as compared with their levels in adjacent healthy tissues. miR‑122 level in the serum was also markedly lower in prostate carcinoma patients in comparison with that in healthy controls. Furthermore, a low serum level of miR‑122 was found to effectively distinguish the prostate carcinoma patients from healthy controls and to be an indicator of poor survival. In prostate carcinoma cells, miR‑122 overexpression inhibited the proliferation and the expression of ROCK2. Taken together, miR‑122 may inhibit the proliferation of prostate carcinoma cells possibly by downregulating ROCK2 expression.