Ganguly Avishek, Basu Soumya, Banerjee Kaushik, Chakraborty Paramita, Sarkar Avijit, Chatterjee Mitali, Chaudhuri Soumitra Kumar
Department of In vitro Carcinogenesis and Cellular Chemotherapy, Chittaranjan National Cancer Institute, 37 SP Mukherjee Road, Calcutta 700 026, India.
Mol Biosyst. 2011 May;7(5):1701-12. doi: 10.1039/c0mb00306a. Epub 2011 Mar 15.
Multidrug resistance (MDR) mediated by the over expression of drug efflux protein P-glycoprotein (P-gp) is one of the major impediments to successful treatment of cancer. P-gp acts as an energy-dependent drug efflux pump and reduces the intracellular concentration of structurally unrelated drugs inside the cells. Therefore, there is an urgent need for development of new molecules that are less toxic to normal cell and preferentially effective against drug resistant malignant cells. In this preclinical study we report the apoptotic potential of copper N-(2-hydroxyacetophenone) glycinate (CuNG) on doxorubicin resistant T lymphoblastic leukaemia cells (CEM/ADR5000). To evaluate the cytotoxic effect of CuNG, we used different normal cell lines (NIH 3T3, Chang liver and human PBMC) and cancerous cell lines (CEM/ADR5000, parental sensitive CCRF-CEM, SiHa and 3LL) and conclude that CuNG preferentially kills cancerous cells, especially both leukemic cell types irrespective of their MDR status, while leaving normal cell totally unaffected. Moreover, CuNG involves reactive oxygen species (ROS) for induction of apoptosis in CEM/ADR5000 cells through the intrinsic apoptotic pathway. This is substantiated by our observation that antioxidant N-acetyle-cysteine (NAC) and PEG catalase could completely block ROS generation and, subsequently, abrogates CuNG induced apoptosis. On the other hand, uncomplexed ligand N-(2-hydroxyacetophenone) glycinate (NG) fails to generate a significant amount of ROS and concomitant induction of apoptosis in CEM/ADR5000 cells. Therefore, CuNG induces drug resistant leukemia cells to undergo apoptosis and proves to be a molecule having therapeutic potential to overcome MDR in cancer.
由药物外排蛋白P-糖蛋白（P-gp）过表达介导的多药耐药性（MDR）是癌症成功治疗的主要障碍之一。P-gp作为一种能量依赖性药物外排泵，可降低细胞内结构不相关药物的浓度。因此，迫切需要开发对正常细胞毒性较小且对耐药恶性细胞优先有效的新分子。在这项临床前研究中，我们报告了甘氨酸铜N-（2-羟基苯乙酮）（CuNG）对多柔比星耐药的T淋巴细胞白血病细胞（CEM/ADR5000）的凋亡潜力。为了评估CuNG的细胞毒性作用，我们使用了不同的正常细胞系（NIH 3T3、Chang肝细胞和人外周血单个核细胞）和癌细胞系（CEM/ADR5000、亲本敏感的CCRF-CEM、SiHa和3LL），得出结论：CuNG优先杀死癌细胞，尤其是两种白血病细胞类型，无论其MDR状态如何，而对正常细胞完全无影响。此外，CuNG通过内源性凋亡途径涉及活性氧（ROS）来诱导CEM/ADR5000细胞凋亡。我们观察到抗氧化剂N-乙酰半胱氨酸（NAC）和聚乙二醇过氧化氢酶可以完全阻断ROS的产生，随后消除CuNG诱导的凋亡，这证实了这一点。另一方面，未络合的配体N-（2-羟基苯乙酮）甘氨酸（NG）未能在CEM/ADR5000细胞中产生大量ROS并伴随诱导凋亡。因此，CuNG诱导耐药白血病细胞凋亡，证明是一种具有克服癌症MDR治疗潜力的分子。
