耐药人白血病细胞GSH含量、GST活力及其同工酶、MRP表达的研究

目的：了解多药耐药基因（ｍｄｒ１）机制以外导致人白血病细胞耐药的因素。方法：采用生化方法，对Ｋ５６２和ＨＬ６０敏感和耐药细胞株谷胱甘肽（ＧＳＨ）含量、谷胱甘肽Ｓ转移酶（ＧＳＴ）活力进行测定；用Ｎｏｒｔｈｅｒｎ杂交对ＧＳＴα、π、μ和多药耐药相关蛋白（ＭＲＰ）ｍＲＮＡ表达进行检测；用Ｗｅｓｔｅｒｎ杂交对ＧＳＴα、π、μ蛋白表达进行检测。结果：与敏感株相比，Ｋ５６２／Ｈ２０和Ｋ５６２／ＶＣＲ的ＧＳＨ含量、ＧＳＴ活力明显增高，ＨＬ６０／Ａｄｒ的ＧＳＨ含量和ＧＳＴ活力无明显增高，Ｎｏｒｔｈｅｒｎ和Ｗｅｓｔｅｒｎ杂交可见ＧＳＴα、π和ＧＳＴπ、μ在Ｋ５６２／Ｈ２０和Ｋ５６２／ＶＣＲ过度表达，ＨＬ６０／Ａｄｒ无ＧＳＴ同工酶过度表达，ＭＲＰ在三种耐药株均有过度表达。结论：ＧＳＨ、ＧＳＴ和ＭＲＰ参与了Ｋ５６２／Ｈ２０和Ｋ５６２／ＶＣＲ耐药，ＨＬ６０／Ａｄｒ耐药与ＧＳＨ、ＧＳＴ无关，与ＭＲＰ有关。在实际应用中，应对多种耐药指标同时进行检测

A study of the GSH contents, GST activity and the expression of GST isoenzyme and MRP in drug-resistant leukemic cell lines]

OBJECTIVE: To understand the non-mdr1 mechanism in multidrug-resistant leukemic cell lines. METHODS: GSH contents and GST activity were measured by biochemical methods, the expression of GST isoenzyme alpha, pi, mu and MRP mRNAs were examined by Northern blot, and the expression of GST alpha, pi, mu proteins were examined by Western blot in sensitive HL-60, K562 and resistant K562/H20, HL-60/Adr, K562/VCR leukemic cell lines, respectively. RESULTS: Compared with K562/S, GSH contents and GST activities were increased in K562/H20 and K562/VCR, and GST alpha, pi or GST mu, pi were overexpressed in K562/H20 or K562/VCR, while there was no difference of GSH contents, GST activities or GST isoenzyme expressions between HL-60/Adr and HL-60/S. The increased expressions of MRP mRNA were revealed in the three resistant cell lines. CONCLUSION: GSH, GST and MRP involved in the drug resistance of K562/H20 and K562/VCR, while only MRP associated with drug resistance of HL-60/Adr.