Tanabe M, Godat D, Kallman R F
Int J Radiat Oncol Biol Phys. 1987 Oct;13(10):1523-32. doi: 10.1016/0360-3016(87)90320-8.
The interaction of cis-diamminedichloroplatinum II (c-DDP) and a course of 5 daily irradiations was investigated in the SCCVII/St tumor and normal tissues (duodenal crypt cells and lung) of the C3H mouse. Two schedules with daily doses of 2.4 mg/kg c-DDP given immediately before 4 Gy X ray on 5 consecutive days and a single 12 mg/kg c-DDP dose followed 24 hr later by the first of 5 daily 4 Gy X ray doses produced the most consistent and significant supra-additive effects on the SCCVII tumor. This supra-additive effect was also achieved with lower and much less toxic drug doses. These schedules produced high enhancement ratios (dose effect factors DEF) for mouse duodenal crypt cells, but the degree of enhancement was less than that for the SCCVII tumor. Schedules with a 72-hr interval between drug and radiation treatments, which produced low enhancement ratios for the SCCVII tumor and duodenal crypt cells, gave high enhancement ratios for the lung. It is concluded that c-DDP has the potential of enhancing the radiation effect on normal tissues, and the degree of enhancement depends upon the interval between X ray and c-DDP. The enhancement ratios for the SCCVII tumors are greater than for normal tissues, and this results in high therapeutic gain factors (TGF). Comparing the effects on tumor with those on normal tissues, it may be seen that there is clinical usefulness in simultaneous combination treatments and perhaps moreso in the administration of a single drug dose 24 hr before the first of 5 daily X ray fractions.
研究了顺二氯二氨铂（c-DDP）与连续5天每日照射方案在C3H小鼠的SCCVII/St肿瘤及正常组织（十二指肠隐窝细胞和肺）中的相互作用。两种方案产生了最一致且显著的超相加效应：一种是连续5天，每天在4 Gy X射线照射前立即给予2.4 mg/kg的c-DDP；另一种是单次给予12 mg/kg的c-DDP，24小时后给予5次每日4 Gy X射线照射中的第一次。较低且毒性小得多的药物剂量也能实现这种超相加效应。这些方案对小鼠十二指肠隐窝细胞产生了高增强率（剂量效应因子DEF），但增强程度低于SCCVII肿瘤。药物与放疗间隔72小时的方案，对SCCVII肿瘤和十二指肠隐窝细胞产生的增强率较低，对肺则产生高增强率。结论是，c-DDP有增强对正常组织辐射效应的潜力，增强程度取决于X射线与c-DDP的间隔时间。SCCVII肿瘤的增强率高于正常组织，这导致了高治疗增益因子（TGF）。比较对肿瘤和正常组织的影响可以看出同时联合治疗具有临床实用性，或许在5次每日X射线分次照射中的第一次之前24小时给予单次药物剂量更具实用性。
