Nanda Dutta – [email protected]; Smarajit Pal – [email protected]; Pratima Mukherjee – [email protected]; Thomas order Aviptadil efferth – [email protected]; Syamal Roy – [email protected]; Soumitra K Choudhuri* – [email protected] * Corresponding authorPublished: 15 November 2006 BMC Cancer 2006, 6:267 doi:10.1186/1471-2407-6-Received: PubMed ID:https://www.ncbi.nlm.nih.gov/pubmed/28242652 27 July 2006 Accepted: 15 NovemberThis article is available from: http://www.biomedcentral.com/1471-2407/6/267 ?2006 Mookerjee et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.AbstractBackground: In search of a suitable GSH-depleting agent, a novel copper complex viz., copper N-(2hydroxyacetophenone) glycinate (CuNG) has been synthesized, which was initially found to be a potential resistance modifying agent and later found to be an immunomodulator in mice model in different doses. The objective of the present work was to decipher the effect of CuNG on reactive oxygen species (ROS) generation and antioxidant enzymes in normal and doxorubicin-resistant Ehrlich ascites carcinoma (EAC/ Dox)-bearing Swiss albino mice. Methods: The effect of CuNG has been studied on ROS generation, multidrug resistance-associated protein1 (MRP1) expression and on activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). Results: CuNG increased ROS generation and reduced MRP1 expression in EAC/Dox cells while only temporarily depleted glutathione (GSH) within 2 h in heart, kidney, liver and lung of EAC/Dox bearing mice, which were restored within 24 h. The level of liver Cu was observed to be inversely proportional to the level of GSH. Moreover, CuNG modulated SOD, CAT and GPx in different organs and thereby reduced oxidative stress. Thus nontoxic dose of CuNG may be utilized to reduce MRP1 expression and thus sensitize EAC/Dox cells to standard chemotherapy. Moreover, CuNG modulated SOD, CAT and and GPx activities to reduce oxidative stress in some vital organs of EAC/Dox bearing mice. CuNG treatment also helped to recover liver and renal function in EAC/Dox bearing mice. Conclusion: Based on our studies, we conclude that CuNG may be a promising candidate to sensitize drug resistant cancers in the clinic.Page 1 of(page number not for citation purposes)BMC Cancer 2006, 6:http://www.biomedcentral.com/1471-2407/6/BackgroundOxidative stress is linked to carcinogenesis as well as to sensitivity or resistance of cancer cells to anticancer drugs [1]. The involvement of reactive oxygen species (ROS) in induction of apoptosis of various cancer cells, especially drug resistant cancers is well known [2-4]. Often, the ability of a therapeutic agent to induce apoptosis of cancer cells depends upon the ability of cancer cells to generate ROS [5]. Moreover, low levels of ROS favor the expression of ABC transporters like P-gp [6]. Drug resistant cancers often show very low levels of ROS. This is usually due to high intracellular reduced glutathione (GSH) levels [7,8] and enhanced activities of antioxidant enzymes like glutathione peroxidase (GPx), catalase (CAT) and superoxide dismutase (SOD) [9]. On the other hand, GSH is also required for phase II detoxification reactions, for example phase II enzymes like glutathione S-transferase (GST) isozy.
