[Vincristine inhibits the proliferation of ovarian cancer cells by regulating the demethylation of RASSF2A].

ABSTRACT

Objective: To investigate the effect of vincristine on the proliferation of ovarian cancer cells by regulating RASSF2A demethylation. Methods: SKOV3 cells were infected with control (LV-NC) and RASSF2A lentivirus (LV-RASSF2A) and treated with or without vincristine. Cell counting kit-8 (CCK-8) was used to detect the activity of ovarian cancer cells (SKOV3) treated with different doses of vincristine. Colony formation assay was used to detect the proliferation of SKOV3 cells. Flow cytometry was used to detect the apoptosis of SKOV3 cells. Real time polymerase chain reaction (RT-PCR) was used to examine the mRNA expression of RASSF2A in IOSE-29 and SKOV3 cells. Western blot was used to examine the protein expression of RASSF2A in IOSE-29 and SKOV3 cells. Methylation-specific PCR was used to detect methylation and demethylation levels of RASSF2A gene in IOSE-29 and SKOV3 cells. Results: The cell viabilities of SKOV3 cell treated with 6.25 nmol/L, 12.5 nmol/L, 25 nmol/L, 50 nmol/L and 100 nmol/L vincristine were (87.19±4.49)%, (73.67±8.62)%, (66.35±6.04)%, (50.32±6.00)% and (34.92±6.11)%, respectively, lower than (100.46±4.69)% of control group (P<0.05). The half maximal inhibitory concentration of vincristine at 48 hours was 50.02 nmol/L. The proliferation abilities of SKOV3 cells in vincristine 12.5 nmol/L group, 25 nmol/L group and 50 nmol/L group were (41.70±2.21)%, (32.15±1.80)% and (23.00±2.01)%, respectively, significantly lower than (100.78±5.66)% in the control group (all P<0.05). The apoptotic rates of SKOV3 cells in vincristine 12.5 nmol/L group, 25 nmol/L group and 50 nmol/L group were (3.65±0.27)%, (5.21±0.76)% and (10.46±1.00)%, respectively, significantly higher than (2.12±0.23)% in the control group (all P<0.05). Compared with the IOSE-29 group (1.00±0.07 and 0.68±0.04), the mRNA expression (0.32±0.04) and protein expression (0.24±0.02) of RASSF2A were down-regulated in SKOV3 cells (P<0.05). Compared with the LV-NC group [(101.60±4.39)%, (100.73±3.29)%, (4.06±0.30)%], over-expression of RASSF2A down-requlated cell viability (68.92±3.94)%, inhibited proliferation (16.38±2.16)%, and promoted apoptosis (8.65±0.56)%, (P<0.05). Conclusion: Vincristine can increase RASSF2A expression and inhibit ovarian cancer cell proliferation by promoting the demethylation of RASSF2A promoter.