A comparison of the inhibitory effects of anti-cancer drugs on thioredoxin reductase and glutathione S-transferase in rat liver

PubMed: 30198440Background: While Thioredoxin Reductase (TrxR) plays an important role in regulation of the intracellular redox balance and various signalling pathways, Glutathione S-Transferase (GSTs) enzymes belong to the detoxification family that catalyse the conjugation of glutathione with various endogenous and xenobiotic electrophiles. Since TrxR and GSTs are overexpressed in many cancer cells, they have been identified as potential targets to develop chemotherapeutic strategies. Method: The mitochondrial TrxR (TrxR2) enzyme and the cytosolic GST enzyme was purified from rat liver via affinity chromatography. After the purification, the in vitro inhibition effects of some anticancer drugs (cisplatin, calcium folinate, carboplatin, epirubicin hydrochloride, doxorubicin hydrochloride, paclitaxel, etoposide, fluorouracil, and methotrexate) were investigated on both enzymes. Since only methotrexate inhibits both enzymes among all the anticancer drugs, a molecular docking study was performed to determine the binding site and the binding affinity of methotrexate to the enzymes. Results: Firstly, TrxR2 and GST were found to have a specific activity of 0.436, 1765 EU/mg proteins with a yield of 39.20%, 31.28% and 207.6, 3516.6 of purification fold, respectively. While TrxR2 was strongly inhibited by all of the anticancer drugs, GST was not inhibited by any of the anticancer drugs except methotrexate. Conclusion: Both enzymes were inhibited by only methotrexate in rat liver, and methotrexate was well placed in the active sites of both proteins. Therefore, it may be argued that methotrexate may be a more effective anticancer drug than all other drugs used in this study against the multi drug resistance that will occur during chemotherapy. © 2018 Bentham Science Publishers.PRJ2015/357, PRJ2015/97This work was financially supported by Ataturk University Scientific Research Projects Coordination Commission (ATAUNI-BAP) with project number PRJ2015/97 and PRJ2015/357. The author(s) have no potential conflict of interest with respect to the research, authorship, and/or publication of this article. Conceived and designed the experiments: Harun Budak gro(up eadler) nda Ilknur Ozgencli. Performed the experiments: Harun Budak, Ilknur Ozgencli, Deryanur Kilic, Ugur Guller, Mehmet Ciftci, and Omer I. Kufrevioglu. Analysed the data: Harun Budak, Ilknur Ozgencli, Deryanur Kilic, and Ugur Guller. Contributed reagents/materials/ analysis tools: Harun Budak. Wrote the paper: Harun Budak, Ilknur Ozgencli, Deryanur Kilic, and Ugur Guller. All authors read and approved the final manuscript

A Comparison of the Inhibitory Effects of Anti-Cancer Drugs on Thioredoxin Reductase and Glutathione S-Transferase in Rat Liver

WOS: 000458732100013PubMed: 30198440Background: While Thioredoxin Reductase (TrxR) plays an important role in regulation of the intracellular redox balance and various signalling pathways, Glutathione S-Transferase (GSTs) enzymes belong to the detoxification family that catalyse the conjugation of glutathione with various endogenous and xenobiotic electrophiles. Since TrxR and GSTs are overexpressed in many cancer cells, they have been identified as potential targets to develop chemotherapeutic strategies. Method: The mitochondrial TrxR (TrxR2) enzyme and the cytosolic CYST enzyme was purified from rat liver via affinity chromatography. After the purification, the in vitro inhibition effects of some anticancer drugs (cisplatin, calcium folinate, carboplatin, epirubicin hydrochloride, doxorubicin hydrochloride, paclitaxel, etoposide, fluorouracil, and methotrexate) were investigated on both enzymes. Since only methotrexate inhibits both enzymes among all the anticancer drugs, a molecular docking study was performed to determine the binding site and the binding affinity of methotrexate to the enzymes. Results: Firstly, TrxR2 and GST were found to have a specific activity of 0.436, 1765 EU/mg proteins with a yield of 39.20%, 31.28% and 207.6, 3516.6 of purification fold, respectively. While TrxR2 was strongly inhibited by all of the anticancer drugs, GST was not inhibited by any of the anticancer drugs except methotrexate. Conclusion: Both enzymes were inhibited by only methotrexate in rat liver, and methotrexate was well placed in the active sites of both proteins. Therefore, it may be argued that methotrexate may be a more effective anticancer drug than all other drugs used in this study against the multi drug resistance that will occur during chemotherapy.Ataturk University Scientific Research Projects Coordination Commission (ATAUNIBAP)Ataturk University [PRJ2015/97, PRJ2015/357]This work was financially supported by Ataturk University Scientific Research Projects Coordination Commission (ATAUNIBAP) with project number PRJ2015/97 and PRJ2015/357. The author(s) have no potential conflict of interest with respect to the research, authorship, and/or publication of this article. Conceived and designed the experiments: Harun Budak (group leader) and Ilknur Ozgencli. Performed the experiments: Harun Budak, Ilknur Ozgencli, Deryanur Kilic, Ugur Guller, Mehmet Ciftci, and Omer I. Kufrevioglu. Analysed the data: Harun Budak, Ilknur Ozgencli, Deryanur Kilic, and Ugur Guller. Contributed reagents/materials/analysis tools: Harun Budak. Wrote the paper: Harun Budak, Ilknur Ozgencli, Deryanur Kilic, and Ugur Guller. All authors read and approved the final manuscript