The role of miRNA-95 in radiosensitivity of cervical cancer cells

Abstract

Objective To detect the expression of miRNA-95 in cervical cancer tissues and cell lines with different radiosensitivity and study the effect of its regulation on radiosensitivity of cervical cancer cells. Methods Real-time PCR was used to detect the expression of miRNA-95 in cervical cancer tissues of 20 patients with radiosensitivity, 20 patients with radiation tolerance, radioresistant cervical cancer cell lines (HeLa, SiHa), and radiosensitive cervical cancer cell lines (Me180). MiRNA-95 mimics (miRNA-95 mimics group)and miRNA-95 inhibition (miRNA-95 inhibition group)were transfected into radioresistant HeLa and SiHa cells by liposome 2000, miRNA-NC was set as control group. CCk-8 assay was used to detect the proliferation of cervical cancer cells irradiated with 60Co γ-rays at 0, 2, 4, 6, 8, 10 Gy. After 4 Gy irradiation, cell clonal formation ability was detected by plate monoclonal assay, and cell apoptosis was detected by flow cytometry. Dual luciferase activity assay was used to detect the target gene of miRNA-95 in cervical cancer cells. Nude mice were used to detect the changes of tumor formation ability. Results The expression of miRNA-95 in cervical cancer tissues of patients with radiotherapy tolerance was significantly higher than that of patients with radiotherapy sensitivity (t=12.279, P<0.05). The expressions of miRNA-95 in HeLa and SiHa cells were significantly higher those that of Me180 cells (t=5.162, 7.114, P<0.05). When the cells were treated with miRNA-95 inhibition, the expression of miRNA-95 in HeLa and SiHa cell lines was significantly lower than that of microRNA-NC group (t=5.162, 7.114, P< 0.05), the cell proliferation rate decreased significantly (t=8.273, 11.354, 13.489, 15.396 and 6.197, 9.185, 10.994, 12.442, P<0.05), the cell monoclonal formation rate decreased significantly (t=8.378, 7.931, P<0.05), and the apoptosis rate increased significantly (t=10.265, 8.386, P<0.05). The tumorigenic weight of nude mice in the miRNA95 inhibition group was significantly decreased (t=8.881, 10.037, P<0.05). Conclusions The miRNA-95 had low levels in both radiosensitive cervical cancer tissues and cells. Inhibiting the expression of microRNA-95 can significantly improve the radiosensitivity of cervical cancer cells by targeting SGPP1 gene. Key words: miRNA-95; Cervical cancer; Radiotherapy sensitivity; Cell proliferation; Apoptosis