Regulation of miRNAs on c-met protein expression in ovarian cancer and its implication.

OBJECTIVE: HGF/c-met signal pathway exerts important roles in tumor pathogenesis. The study of c-met related regulatory mechanism provides the basis for finding anti-tumor molecular drugs. MiRNAs can effectively regulate gene expression and work as gene therapy. The identification of miRNAs for c-met regulation and study of related mechanism are of critical importance.

MATERIALS AND METHODS: Bioinformatics approach was used to search for possible miRNAs with regulatory functions on c-met gene. Using pcDNA3.1-EGFP as the scaffold, miRNAs over-expression and inhibitor plasmids were constructed for electroporation-transfection in ovarian cell line ES-2, and pcDNA3.1-EGFP empty plasmid was used as the control group. qRT-PCR and Western blot were applied to measure c-met mRNA and protein expression, followed by transwell chamber in vitro assay for the evaluation of invasion potency.

RESULTS: Bioinformatics prediction showed favorable regulatory function on c-met gene by miR-204. The differential expressions of EGFP were observed between pcDNA3.1-EGFP-204-up and inhibitor plasmid pcDNA3.1-EGFP-204-down. After transfection for 24 h and 48 h, c-met expression in miR-204 over-expression group gradually decreased (p<0.05 compared to control group), accompanied with reducing cell migration or invasion potency in a time dependent manner (p<0.05). In contrast, no significant difference in the level of c-met was found in the inhibitor group and control group (p>0.05).

CONCLUSIONS: The up-regulation of miR-204 suppressed the expression of c-met in ovarian cancer cells and inhibited cell infiltration. The suppression of miR-204 expression, however, presented no significant impact on cell infiltration potency.