Aim: Although aberrant miRNA expression has been documented, altered miR-101 expression in cervical cancer and its carcinogenic effects and mechanisms remain unexplored. The aim of our study was to investigate the role of miR-101 alteration in cervical carcinogenesis.
Methods: Expression of miR-101 was examined by quantitative real-time reverse transcriptase PCR (qRT-PCR) in Hela cells. After modulating miR-101 expression using miR-101 mimics, cell growth, apoptosis and proliferation, and migration were tested separately by MTT or flow cytometry and cell wound healing assay and protein expression was detected by qRT-PCR. The expression of COX-2 in Hela cell was also examined by immunohistochemical staining and the correlation with miR-101 expression was analysed.
Results: The miR-101 demonstrated significantly low expression in Hela cell. When we transfected miR-101 mimics into Hela cells, the modulation of miR-101 expression remarkably influenced cell proliferation, cycling and apoptosis: 1) The expression of microRNA-101 tended to increase after transfection; 2) Overexpression of miR-101 was able to promote cell apoptosis, the apoptosis rate being markedly higher (97.6%) than that seen pre-transfection (12.2%) (P <0.05); 3) The miR-101 negatively regulates cell migration and invasion, scratch results being lower (42.7um±2um) than that observed pre-transfection (181.4 um±2 um); 4) miRNA-101 inhibits the proliferation of Hela cells as well as the level of COX-2 protein, which was negatively correlated with miR-101 expression.
Conclusions: Overexpression of miR-101 has obvious inhibitory effects on cell proliferation, migration and invasion. Thus reduced miR-101 expression could participate in the development of cervical cancer at least partly through loss of inhibition of target gene COX-2, which probably occurs in a relative late phase of carcinogenesis. Our data suggest an important role of miR-101 in the molecular etiology of cancer and indicate potential application of miR-101 in cancer therapy.