Abstract: Objective To construct an ovarian cancer cell line stably overexpressing XAF1 gene and observe the effects of XAF1 gene overexpression on proliferation, apoptosis, cell cycle and sensitivity to paclitaxel of the cells. Methods Ovarian cancer A2780 cells were transfected with the plasmids pcDNA3.1(+) or pcDNA3.1(+)-XAF1, and the cells stably Over expressing XAF1 (A2780/XAF1 cells) were screened using G418. Cell clone formation assay and CCK8 assay were used to evaluate the changes in proliferation and paclitaxel sensitivity of the transfected cells, and cell cycle and apoptosis of the cells were analyzed using flow cytometry. Results We successfully obtained A2780/XAF1 cells stably overexpressing XAF1, which exhibited no significant changes in cell morphology. Compared with the negative control cells (A2780/NC), A2780/XAF1 cells had lowered clone formation ability (P=0.0016) and attenuated proliferative activity on the first (P=0.009) and third (P=0.0035) days after cell adherence with also a significantly increased percentage of cells in G2-M phase (P<0.001). A2780/XAF1 cells showed significantly higher apoptosis rates than A2780/NC cells in the absence of apoptotic stimulation, in serum-free culture or following paclitaxel induction (P<0.001). The proliferative activity of A2780/XAF1 cells was significantly lower than that of A2780/NC cells after exposure to different paclitaxel concentrations (P<0.001). The half inhibitory concentration of paclitaxel was significantly lower in A2780/XAF1 than in A2780/NC cells. Conclusion Overexpression of XAF1 significantly inhibits the proliferation, induces cell cycle arrest, promotes apoptosis, and increases paclitaxel sensitivity in ovarian cancer cells.

Key words: ovarian cancer; XAF1 gene; cell proliferation; paclitaxel; cell apoptosis; cell cycle