Oxidative Stress Modulation and Radiosensitizing Effect of Quinoxaline-1,4-Dioxides Derivatives.

Background: Quinoxaline-1,4-dioxide (QNX) derivatives are synthetic heterocyclic compounds with multiple biological and pharmacological effects. Objective: In this study, we investigated the oxidative status of quinoxaline-1,4-dioxides derivatives in modulating melanoma and glioma cell lines, based on previous results from the research group and their capability to promote cell damage by the production of Reactive Oxygen Species (ROS). Methods: Using in vitro cell cultures, the influence of 2-amino-3-cyanoquinoxaline-1,4-dioxide (2A3CQNX), 3-methyl-2-quinoxalinecarboxamide-1,4-dioxide (3M2QNXC) and 2-hydroxyphenazine-1,4-dioxide (2HF) was evaluated in metabolic activity, catalase activity, glutathione and 3-nitrotyrosine (3-NT) quantitation by HPLC in malignant melanocytes (B16-F10, MeWo) and brain tumor cells (GL-261 and BC3H1) submitted to radiotherapy treatments (total dose of 6 Gy). Results: 2HF increased the levels of 3-NT in non-irradiated MeWo and glioma cell lines and decreased cell viability in these cell lines with and without irradiation. Conclusion: Quinoxaline-1,4-dioxides derivatives modulate the oxidative status in malignant melanocytes and brain tumor cell lines and exhibited a potential radiosensitizer in vitro action on the tested radioresistant cell lines.