MicroRNA-301a promotes migration and invasion by targeting TGFBR2 in human colorectal cancer

Background: micrornas (mirnas) have been reported to play crucial roles in regulating a variety of genes pivotal for tumor metastasis. microrna-301a (mir-301a) is overexpressed and displays oncogenic activity in many cancers. however,little is known about the potential roles of mir-301a in colorectal cancer (crc). methods: taqman probe stem-loop real-time pcr was used to quantitatively measure the expression level of mir-301a in 48 cases of crc tissues and the matched adjacent non-tumor mucosa as well as in crc cell lines. mir-301a mimics and inhibitors were used to up-regulate and down-regulate mir-301a in crc cells,respectively; lentivirus was used to construct mir-301a stably up- and down-regulated crc cell lines. metastasis ability was evaluated by transwell and wound healing assays while invasion was measured by transwell coated with matrix gel in vitro; in vivo metastasis was performed on nude mice model. the target of mir-301a was predicted by targetscan software and validated by qrt-pcr,immunohistochemistry,western blot and luciferase reporter gene assay. results: the expression of mir-301a was significantly higher in lymph node metastasis positive crc samples compared with negative ones. downregulation of mir-301a significantly inhibited the migration and invasion both in vitro and in vivo while forced up-regulation of mir-301a promoted migration and invasion. tgfbr2 was identified to be the downstream target of mir-301a. knockdown of tgfbr2 in cells treated by mir-301a inhibitor elevated the previously abrogated migration and invasion. conclusions: our data indicated that mir-301a correlated with the metastatic and invasive ability in human colorectal cancers and mir-301a exerted its role as oncogene by targeting tgfbr2. © 2014 zhang et al.; licensee biomed central.