Decreased expression of microRNA-625 is associated with tumor metastasis and poor prognosis in patients with colorectal cancer

Background MicroRNAs (miRNAs) play an essential role in colorectal cancer (CRC) development and progression. Aberrant miR-625 expression has been reported in several cancers. However, the clinical significance of miR-625 in human CRC has not been addressed. Methods miR-625 expression was determined in 96 pairs of primary CRC and their corresponding adjacent nontumor tissues by quantitative reverse transcriptase-polymerase chain reaction. Associations of miR-625 expression with demographic and clinicopathologic features were determined. Additionally, the effects of ectopic expression of miR-625 on cell migration and invasion were investigated in vitro and in vivo. Results miR-625 was significantly downregulated in CRC tissues and cell lines. In addition, the decreased expression of miR-625 was positively associated with advanced lymph node metastasis (P = 0.038), liver metastasis (P = 0.031), poor overall survival (P = 0.002), and an unfavorable prognosis for CRC patients, as determined through a multivariate analysis (P = 0.034). Moreover, functional assays demonstrated that ectopic miR-625 expression inhibits the invasion and migration of HCT116 CRC cells both in vitro and in vivo. Conclusions Our results suggest that miR-625 may serve as an efficient clinical biomarker and a therapeutic tool for the inhibition of metastasis in CRC. J. Surg. Oncol. 2013 108:230–235. © 2013 Wiley Periodicals, Inc.