MicroRNA-26a inhibits cell migration and invasion in cervical cancer through targeting high mobility group protein A1(HMGA1)

Objective To investigate the role of microRNA-26a (miR-26a) in cell migration and invasion in cervical cancer and its regulatory effects on high mobility group protein A1 (HMGA1). Methods Both HeLa and SiHa cells were divided into four groups: miR-26a mimic group, mimic control group, miR-26a inhibitor group and inhibitor control group. MiR-26a expression was evaluated by quantitative real-time polymerase chain reaction (qRT-PCR). Target genes for miR-26a-5p were predicted by bioinformatics and verified by dual-luciferase reporting system. HMGA1 expression was evaluated by Western blot and qRT-PCR. Cell migration and invasion were analyzed by in vitro assays. Results (1) HMGA1 was predicted as one of the potential targets of miR-26a by TargetScan. Results of dual-luciferase activity assay further confirmed that HMGA1 was directly regulated by miR-26a. (2) Expression of miR-26a and HMGA1 at mRNA level was respectively enhanced and inhibited in miR-26a mimic-transfected HeLa as well as SiHa cells as compared with those in the corresponding mimic control groups (P<0.05). On the contrary, expression of miR-26a and HMGA1 at mRNA level was respectively reduced and increased in miR-26a inhibitor groups as compared with those in the corresponding inhibitor control groups (P<0.05). (3) Expression of HMGA1 in miR-26a mimic-transfected HeLa and SiHa cells was lower than that in the corresponding mimic control groups (P<0.05). But expression of HMGA1 in miR-26a inhibitor groups was higher than that in the corresponding inhibitor control groups (P<0.05). (4) Abilities of cell migration and invasion were suppressed in miR-26a mimic groups as compared with those in the corresponding mimic control groups, but were enhanced in miR-26a inhibitor groups as compared with those in the corresponding inhibitor control groups (P<0.05). Conclusion MiR-26a can inhibit the proliferation and invasion of HeLa and SiHa cells through targeting HMGA1, suggesting that miR-26a is closely related to cervical cancer and might be associated with chemotherapy resistance in cervical cancer. This study might provide a new strategy for the prevention and treatment of cervical cancer. Key words: Cervical cancer; MiR-26a; Migration; Invasion; HMGA1