Radiosensition of a human non-small lung cancer cell line A_(549) by endostatin / 西安交通大学学报(医学版)

ABSTRACT

Objective To study the synergistic effect of endostatin (YH-16) and irradiation on human non-small cell lung cancer (NSCLC) cell line A549 and the expression level of vascular endothefial growth factor. Methods ① A549 cells were exposed to various concentrations of endostatin for different time. The optimal concentration giving ≤20% inhibition concentration (IC20) by MTT assay was selected. ② The cells were divided into 4 groupscontrol group,chemotherapy alone,radiotherapy alone,and radio-chemotherapy group. All groups were exposed in distinct treatment,the cells survival fraction and the plating efficiency of the four groups provided to select the optimal radiotherapy dosage. ③ The radio-chemotherapy group had been exposed to endostatin for 48 hours,followed by irradiation at 48 hours with various doses0,2,4,6,8 Gy. After 14 days,the cell clonogenic survival curves and the SER were evaluated. ④ Detect the different groups' VEGF value by ELISA kit. Results Incubating cells in 200 mg/L endostatin culture medium the value of SER radiated by linear accelerator in 2 Gy after 48 h were 1.61 and 1.04. And endostatin with proper dosage and radio-exposure time could decrease the VEGF level. Conlusion It is suggested that endostatin enhances the radiosensitivity of NSCLC A549 cell line in vitro (SER=1.61,1.04). The enhancement depends on the time of exposure drug. The optimal radiation time should be 48 hour after exposure.