Hu X, Chen W Y
Cancer Institute, Zhejiang Medical University, Hangzhou, China.
Zhongguo Yao Li Xue Bao. 1994 Sep;15(5):422-6.
Our purpose was to test whether drug sensitivity and drug accumulation in MDR cell erythroleukemic K562r could be restored by incubating cells with 3 anthracycline antibiotics in combination. Drug sensitivities of cells were assessed with MTT assay, in which doxorubicin, epirubicin, daunorubicin, or the 3-drug mixture was applied with concentrations ranging from 1 to 3125 ng.ml-1. The IC50 of K562r cells were 1.0, 1.0, 0.1, and 0.2 microgram.ml-1, respectively, about 22, 16, 10, and 20 times higher than those of K562 cells. After cells were exposed to doxorubicin (2-32 micrograms.ml-1) for 1 h, the drug concentrations in K562r cells were all higher than those in K562 cells. Similar results were obtained for epirubicin or daunorubicin. After 1-h incubation of cells with the 3-drug mixture (3 to 192 micrograms.ml-1), there were no considerable differences of drug accumulation between K562r and K562 cells with only 3 exceptions in 21 groups. It is concluded that restoration of intracellular drug accumulation in MDR cell line K562r was not correlated with reversal of its drug resistances.
我们的目的是测试将多药耐药（MDR）细胞系红白血病K562r与3种蒽环类抗生素联合孵育，是否能恢复其药物敏感性和药物蓄积。采用MTT法评估细胞的药物敏感性，其中阿霉素、表柔比星、柔红霉素或这3种药物的混合物的应用浓度范围为1至3125 ng.ml-1。K562r细胞的半数抑制浓度（IC50）分别为1.0、1.0、0.1和0.2 μg.ml-1，分别比K562细胞高约22、16、10和20倍。细胞暴露于阿霉素（2至32 μg.ml-1）1小时后，K562r细胞中的药物浓度均高于K562细胞。表柔比星或柔红霉素也得到了类似结果。细胞与3种药物的混合物（3至192 μg.ml-1）孵育1小时后，K562r细胞和K562细胞之间的药物蓄积没有显著差异，21组中只有3个例外。得出的结论是，MDR细胞系K562r细胞内药物蓄积的恢复与其耐药性的逆转无关。
