Expression of OCT-4 in cervical cancer patients with different radiosensitivity and effect of OCT-4 knockdown on radiosensitivity of cervical cancer cells

Abstract

Objective To study the expression of OCT-4 in tumor tissues of cervical cancer patients with different radiosensitivity, and to explore the effect of OCT-4 knockdown on radiosensitivity of human cervical squamous carcinoma Siha cells and its mechanism. Methods Real-time PCR and Western-blot were used to determine the mRNA and protein expression of OCT-4, respectively, in tumor tissues of cervical cancer patients with different radiosensitivity. The Siha cells were transfected with OCT-4-SiRNA to construct the OCT-4 knockdown cell line (OCT-4 SiRNA group). The control group and NC transfection group were also set up. The Siha cells in each group were exposed to different doses of X-ray. The MTT assay and colony formation assay were used to evaluate cell proliferation and colony formation ability in each group, respectively. Flow cytometry was used to assess apoptosis and cell cycle in each group. Western blot was used to measure the expression of cleaved caspase-3 and p-Akt in each group. Results With the decrease in radiosensitivity of patients with cervical cancer, the mRNA and protein expression of OCT-4 in tumor tissues were significantly increased (P<0.05). Compared with the control group and the NC group, the OCT-4 SiRNA group had a significantly increased cell proliferation inhibition rate, significantly weaker colony formation ability, significantly enhanced apoptosis and cell cycle inhibition, significantly higher expression of cleaved caspase-3, and significantly lower expression of p-Akt after exposure to different doses of X-ray (all P<0.05). Conclusions OCT-4 expression is negatively correlated with the radiosensitivity of patients with cervical cancer. OCT-4 knockdown enhances the radiosensitivity of human cervical squamous carcinoma Siha cells by promoting the expression of cleaved caspase-3 and inhibiting the expression of p-Akt. Key words: OCT-4 gene; Cervical neoplasms/radiotherapy; Siha cells line; OCT-4 gene silence; Radiosensitivity