应用DNA损伤与修复测定法研究肿瘤细胞的放射敏感性

The Studies of Radiation Sensitivity of Tumor Cells by Using Determinating Method of DNA Damage and Repair

摘要: 应用硷洗脱法研究了⁶⁰Cor射线及其联合高温对L(5178Y)细胞的DNA链断裂与修复的影响。结果表明, 43℃加温30min能显著抑制r射线引起DNA断裂后的修复, 照前加温的增敏效果更好。又应用羟基磷灰石层析法分析HL-60细胞和HL-60(VCR)细胞受照后两者DNA单链断裂程度无显著差异, 而DNA断链的修复能力有非常显著差异, 反映HL-60(VCR)细胞的重接修复能力高, 提示耐药的白血病细胞对辐射的敏感性较低。

Abstract: The effects of ⁶⁰Co r-rays and its combination with hyperthermia on DNA strand breaks and their repair in L5078Y cells were studied using alkaline elution technique. When cells were heated at 43℃ for 30 min there was obvious inhibition of its repair in DNA damage caused by r-irradiation. The inhibiting effect of hyperthermia before irradiation was better. The effects of radiation on DNA strand breaks and its repair in HL-60 cells and HL-60(VCR) cells were analyzed by using technique of hydroxylapatite chromatography. The extent of DNA strand breaks in HL-60 cells and HL-60(VCR) cells induced by irradiation was no markedly different. But the repair ratio of strand breaks in HL-60(VCR) cells was higher than that in HL-60 cells, The difference was obvious. The results suggest that the heterogeneity of radiosensitivity of leukemia cells is correlated with its drug resistance.