Radiosensitizing Effect Of 4-HPR On Human Cholangiocarinoma Cell Line QBC939

Objective:To study and discuss the mechanism of radiosensitization of fenretinide (4-HPR) on human cholangiocarinoma cell line QBC939.Provide abasis for treatment in the treatment of cholangiocarinoma.Methods:MTT assay was used to determine the IC50 (half maximal inhibitory concentration) of 4-HPR on QBC939 cells. Radiosensitization of 4-HPR was measured by clone formation assay, and survival curve was described. Alterations in cell apoptosis was tested by flow cytometry. The apoptosis associated protein were analyzed by western blot.Results:4-HPR inhibition of QBC939 cell proliferation dependent on the concentration. Compared with group Radiotherapy Alone, cells in the 4-HPR+Radiotherapy group showed a lower overall survival rate. The mean lethal radiation dose (Do) of the two group were 2.72 and 1.93Gy, prospective domain dose (Dq) were 2.06 and 0.94Gy, respectively. To the 4-HPR, the gain ratio of radiotherapy (SER) was 1.41. The cells apoptosis rate was higher after 4-HPR treatment, determined by flow cytometry and western blot.Conclusion:The 4-HPR inhibits the QBC939 cell growth and enhances the radiosensitivity of QBC939 cells in vitro. The radiosensitizing mechanisms might be related to apoptosis.