Wu D Z, Zhang Y Q, Keng P, Sutherland R M, Lasagna L
Int J Radiat Oncol Biol Phys. 1985 Dec;11(12):2125-31. doi: 10.1016/0360-3016(85)90093-8.
Chinese hamster ovary (CHO) cells were exposed to various concentrations of bleomycin (BLM) for 0.5, 1, 2, 4, 6, or 24 hours, followed with graded doses (0 to 800 rad) or radiation. The response to this chemotherapy-radiation combination treatment was measured by cell survival studies and DNA damage as determined by alkaline elution assay. Isobolograms for 1 and 2 log cell kills showed that cytotoxicity from BLM and from radiation were additive at 4, 15 and 75 milliunit/ml (mu/ml) for 1 or 4 hour exposure. When the exposure time of BLM was extended to 24 hours, slightly supraadditivity of lethality was found for the combination treatment with pharmacologically pertinent concentrations of 4 or 15 mu/ml. Therefore 4, 15 and 75 mu/ml concentrations of BLM all interacted positively with all doses of radiation to give enhanced cell kill. The alkaline elution patterns from the BLM-radiation combination also showed an enhancing effect on single strand breaks of DNA from treated cells. A human oat cell carcinoma cell line (MEMAR cells) was also studied and found to be more sensitive to BLM than were CHO cells.
将中国仓鼠卵巢（CHO）细胞暴露于不同浓度的博来霉素（BLM）中0.5、1、2、4、6或24小时，随后给予分级剂量（0至800拉德）的辐射。通过细胞存活研究和碱性洗脱试验测定的DNA损伤来衡量对这种化疗 - 放疗联合治疗的反应。1和2个对数细胞杀伤的等效线图表明，对于1或4小时的暴露，在4、15和75毫单位/毫升（mu/ml）时，BLM和辐射的细胞毒性是相加的。当BLM的暴露时间延长至24小时时，发现与4或15 mu/ml的药理学相关浓度联合治疗时，致死率有轻微的超相加性。因此，4、15和75 mu/ml浓度的BLM均与所有剂量的辐射产生正向相互作用，从而增强细胞杀伤。BLM - 辐射联合处理后的碱性洗脱模式也显示对处理细胞的DNA单链断裂有增强作用。还研究了一种人燕麦细胞癌细胞系（MEMAR细胞），发现其对BLM比CHO细胞更敏感。
