miR-519d靶向p21调控宫颈癌细胞增殖的初步研究

IM：To explore the regulatory effect of miR-519d on cell proliferation, cell cycle and the expression of its target gene p21 in cervical cancer cells. METHODS: The miR-519d inhibitor was used to regulate the endogenous expression of miR-519d, and its expression levels in cervical cancer cells were determined by quantitative real-time PCR. Then, the effects of miR-519d inhibitor on proliferation were evaluated by MTT assay, while cell cycle distributions were measured by flow cytometry. Moreover, luciferase reporter assays were used to confirmed whether p21 is a target of miR-519d. And changes in mRNA and protein levels of p21 were assessed in HeLa and SiHa cells with over-expression of miR-519d by quantitative real-time PCR and Western blot, respectively．RESULTS: The results showed that miR-519d expression level exhibited a significant decrease after transfection with miR-519d inhibitor. While suppression of miR-519d markedly attenuated the proliferation of HeLa and SiHa cells. Furthermore, flow cytometrical analysis indicated that transfection of miR-519d inhibitor augmented the proportion of cells in G1 phase, whereas reduced cells in S phase. In addition, the results of dual luciferase assays validated p21 as a novel target gene of miR-519d in cervical cancer cells. Transfection with miR-519d mimics led to apparent downregulation of p21 both at the mRNA and protein levels. CONCLUSION: Our findings suggest that miR-519d could promote cell proliferation, accelerate cell cycle progression by targeting p21, hence highlighting its potential as an oncogene in cervical cancer cells.