MiR-135a promotes growth and invasion of colorectal cancer via metastasis suppressor 1 in vitro

摘要

MicroRNAs (miRNAs) are small non-coding RNAs that participate in the spatiotemporal regulation of messenger RNA and protein synthesis.Aberrant miRNA expression leads to developmental abnormalities and diseases.The miR-135a is considered to be oncogenic; however,the functions and mechanisms of miR-135a in colorectal cancer (CRC) are largely unknown.Thus,we investigated the functions and mechanisms of miR-135a,especially its relationship with the metastasis suppressor 1 (MTSS1) gene in CRC.The expression of miR-135a was determined by real-time polymerase chain reaction,while its effect on cell proliferation,migration,and invasion was determined by MTT,without and with matrigel,respectively.The expression of MTSS1 was detected by western blot analysis.It was found that miR-135a expression was higher in human CRC samples than in non-tumor control tissue.Using SW480 and SW620 CRC cell lines,increased proliferation was observed in response to miR135a.We also demonstrated that miR-135a promoted mobility and invasion via transwell assay with and without Matrigel,respectively,of CRC cells.In contrast,inhibition of miR-135a reduced their proliferative and invasive capability.MTSS1 was identified as a candidate target gene of miR-135a by luciferase report assay.Western blot analysis showed that the expression of MTSS1 was regulated by miR-135a overexpression and knockdown.Similarly,miR-135a-mediated cell mobility and invasion were reduced after MTSS1 was knocked down by small interfering RNA.These data indicated that miR-135a promotes the growth and invasion of CRC cells,at least partially,through targeting MTSS1.