miR-205 is frequently downregulated in prostate cancer and acts as a tumor suppressor by inhibiting tumor growth

Abstract

The purpose of this study was to elucidate the molecular mechanisms of microRNA-205 (miR-205) as a tumor suppressor in prostate cancer (PCa). In the present study, microRNA microarray analysis suggested that the expression of miR-205 was significantly decreased in advanced PCa compared with early PCa. Real-time PCR analysis also indicated that miR-205 expression was significantly decreased in PCa tissues compared with non-cancerous tissues. Moreover, the expression of miR-205 has been demonstrated to be associated with the clinicopathological stage and total/free prostate-specific antigen (PSA) level of PCa. Functional analyses showed that both the overexpression of miR-205 and the knockdown of c-SRC in PCa cell lines could inhibit cell growth, colony formation, migration, invasion and the cell cycle as well as induce cell apoptosis in vitro. Furthermore, over-expressing miR-205 reduced tumorigenicity in vivo. Through a luciferase activity assay and Western blotting, c-SRC was identified as a target of miR-205 in cells. The overexpression of miR-205 suppressed c-SRC and its downstream signaling molecules, including FAK, p-FAK, ERK1/2 and p-ERK1/2, and attenuated cell proliferation, invasion and tumor growth.

miR-205 in Situ Expression and Localization in Head and Neck Tumors - a Tissue Array Study

“…miR-205 expression is dysregulated in many human cancers, influenced various cancer cell properties in cell lines and also regulated several major cancer pathways (Xie et al, 2012;Lei et al, 2013;Su et al, 2013;Wang et al, 2013). However, pattern of miR-205 expression in head and neck cancers demonstrated conflicting results.…”

Microdissecting the role of microRNAs in the pathogenesis of prostate cancer

“…This MET and the acquisition of a more epithelial phenotype is concomitantly accompanied by an increase in epithelial markers and a significant concurrent reduction of various cell invasive markers, including ERBB3, PRKCE (PKCe), ZEB2, E2F1, E2F5, and CHN1 (N-chimaerin) (60). Wang and his colleagues (61) have recently shown that the ectopic expression of miR-205 in PCa cells inhibits tumor growth and invasion through suppression of the c-SRC gene and its various downstream signaling molecules. Furthermore, miR-205 together with miR-31 promote apoptosis induced by chemotherapeutic agents via the repression of various antiapoptotic genes, including BCL2L2 and E2F6 (62).…”

MiR-205 promotes motility of ovarian cancer cells via targeting ZEB1

“…expression [31]; miR-205 has been indicated as a novel regulator of the anti-apoptotic protein Bcl2 in prostate cancer [32]; miR-205 has also been reported to affect infiltration and metastasis of breast cancer by post-transcriptional inhibition of HER3 expression [18]. These findings show the conflicting functions of miR-205 in different cancers.…”