Deciphering of The Effect of Chemotherapeutic Agents on Human Glutathione S-Transferase Enzyme and MCF-7 Cell Line

Abstract

Background: Cancer is the disease that causes the most death after cardiovascular diseases all over the world these days. Breast cancer is the most common type of cancer among women and ranks the second among cancer-related deaths after lung cancer. Chemotherapeutics act by killing cancer cells, preventing their spread and slowing their growth. Recent studies focus on the effects of chemotherapeutics on cancer cells and new chemotherapy approaches that targeting enzymes that catalyze important metabolic reactions in the cell. Objective: The aim of this study was to investigate the effects of chemotherapeutic agents, Tamoxifen and 5-FU, on MCF-7 cell line and human erythrocyte GST, an important enzyme of intracellular antioxidant metabolism. Methods: In this study, it was investigated that the effect of chemotherapeutic agents, Tamoxifen and 5-FU, on MCF-7 breast cancer cell line and performed ROS analyzes. In addition, it was purified glutathione S-transferase (GST), one of the important enzymes of intracellular antioxidant mechanism, from human erythrocytes by using ammonium sulfate precipitation and glutathione agarose affinity chromatography, and investigated in vitro effects of chemotherapeutic agents, 5-FU and Tamoxifen, on the activity of this enzyme for the first time. Results: It was determined that Tamoxifen and 5-FU inhibited cellular viability and 5-FU increased intracellular levels of ROS, whereas Tamoxifen reduced intracellular levels of ROS. In addition, human erythrocyte GST enzyme with 16.2 EU/mg specific activity was purified 265.97-fold with a yield of 35% using ammonium sulfate precipitation and glutathione agarose affinity chromatography. The purity of the enzyme was checked by the SDS-PAGE method. In vitro effects of chemotherapeutics, 5-FU and Tamoxifen, on GST activity purified from human erythrocytes were investigated. The results showed that 5-FU increased the activity of GST in the concentration range of 77 to 1155 µM and that Tamoxifen increased the activity of GST in the concentration range of 0.54 to 2.70 µM. Conclusion: In this study, the effects of tamoxifen and 5-FU chemotherapeutic agents on both MCF-7 cell line and human GST enzyme were examined together for the first time. Our study showed that chemotherapeutic agents (5-FU and Tamoxifen) inhibited cellular viability and Tamoxifen reduced intracellular levels of ROS whereas 5-FU increased intracellular levels of ROS. In addition, 5-FU and Tamoxifen were found to increase the activity of GST enzyme purified from the human erythrocyte.

The in vitro effect of 5-FU and Tamoxifen Chemotherapeutics on penthose phosphate pathway enzymes

“…The results of this study showed that both 5-FU and tamoxifen increase the GST enzyme activity. The results of this study are similar to the results of our study [6]. In a different study, it was determined that 5-FU coumarin derivatives showed a potent and totally selective inhibitory action against the target CA IX/XII enzyme activities [40].…”

“…Chemotherapeutics inhibit the growth and proliferation of the tumor and other rapidly growing cells [2]. However, chemotherapeutics can damage organs such as the liver and kidneys during the treatment process, cause inhibition of various metabolic enzymes, prolong the treatment process and negatively affect the patient's well-being [3][4][5][6][7]. The fluoropyrimidine 5fluorouracil (5-FU) and its prodrug Capecitabine are widely used chemotherapeutic agent in the treatment of gastrointestinal, breast, head and neck cancers.…”

Bortezomib ile Kalp Hasarı Oluşturulan Ratlarda Berberinin Oksidatif ve Nitrozatif Stres Üzerine Etkisi

“…Tümör hücrelerinde hayati hücresel yolları hedefleyen yeni ilaçların kullanımı, neoplastik hastalıklar için tedavi sonuçlarını önemli ölçüde iyileştirmiştir [27,28]. Bcr-Abl antagonistleri, monoklonal antikorlar ve proteazom inhibitörleri gibi ilaçlarla hematolojik malignitelerin tedavilerinde iyi sonuçlar elde edilmiştir.…”

“…Önceki çalışmalarda çeşitli toksik ajanların ROS üretimine bağlı olarak lipid peroksidayonu meydana getirdiğini ve buna bağlı olarak MDA seviyelerinde artışların olduğu bildirilmiştir [40][41][42][43][44]. Artan MDA seviyelerinin oksidatif stresin önemli bir göstergesi olduğunu ve oksidatif stresin de kalp dahil çeşitli dokularda toksisiteye yol açtığı yapılan çalışmalarda kanıtlanmıştır [28,[45][46][47] [15]. Biyolojik sistemlerdeki serbest radikallerin ortadan kaldırılması, serbest radikallere karşı önemli savunma sistemleri olarak işlev gören enzimatik ve enzimatik olmayan antioksidanlar tarafından sağlanır [48][49][50][51][52].…”

Characterization of glutathioneS‐transferase enzyme from brown meagre (Sciaena umbra) and inhibitory effects of heavy metals

“…One of the most significant antioxidant defense systems is the glutathione (GSH) mechanism. GSH metabolism, including GST enzyme, contains a variety of enzymatic antioxidant components that are reported in several studies [5][6][7]. GST has a vital role in xenobiotic metabolism.…”