The method of establishing the hypoxic SKOV3 cellular model in the research of radiotherapy sensitizer

Objective: To investigate the suitable method of establishing the hypoxic SKOV3 cellular model in the research of radiotherapy sensitizer. Methods: Human ovarian cancer cell line SKOV3 were divided into three groups: normoxic control group, cobalt chloride group and environmental hypoxia group. Cell proliferation of each group 72 h after single X-ray irradiation (0, 2, 4, 6, 8 Gy) were detected by MTT assay. Results: Cell proliferation of non-irradiated cells in cobalt chloride group and environmental hypoxia group were significantly lower than that in normoxic control group (t = 24.789, 196.960, both P < 0.01). Cell viability of the cells in normoxic control group and cobalt chloride group were significantly decreased after receiving a single X-ray irradiation of different doses compared with non-irradiated cells in the same group (F = 2263.039, 3672.044, both P < 0.01) and their cell viability were decreased with the increase of radiation dose, while environmental hypoxia group had no significant change (F = 1.412, P > 0.05). The cell viability of irradiated cells in environmental hypoxia group were significantly higher than the irradiated cells with the same radiation in normoxic control group and cobalt chloride group (2 Gy: F = 61.125; 4 Gy: F = 181.825; 6 Gy: F = 373.830; 8 Gy: F = 2425.510, all P < 0.01). Conclusions: Cells in environmental hypoxia group were very resistant to radiation. Their radiation sensitivity strikingly decreased and the killing effect of radiation on them was weak. The hypoxic cellular model of environmental hypoxia group was obviously superior to cobalt chloride group. Environmental hypoxia method was more suitable to establish the hypoxic SKOV3 cellular model in the research of radiotherapy sensitizer compared with cobalt chloride. (authors)