Role of Nuclear Factor Erythroid 2-Related Factor 2 (NRF-2) Mediated Antioxidant Response on the Synergistic Antitumor Effect of L-Arginine and 5-Fluro Uracil (5FU) in Breast Adenocarcinoma.

Breast adenocarcinoma (BAC) in glandular tissue cells have excessive metastasis and invasion capability. The major challenges for the chemotherapy used for the management of BAC include chemoresistance and auto-immunosuppression in BAC. The 5-fluro uracil (5-FU) based therapy promotes the immune activation in BAC by targeting the regulatory T cells and myeloid-derived suppressor cells (MDSC). The beneficial effect of the combination of L-Arginine with 5-FU strives to be established in different pre-clinical and clinical conditions and explored in the scientific literature. L-Arginine induces NO production and potentiates the anticancer effect of 5-FU. NO-mediated signaling is regulated by nuclear factor erythroid 2-related factor 2 (NRF-2) mediated antioxidant response. NRF-2 mediated antioxidant mechanism always suppresses the formation of superoxide (O2-) as well as other reactive oxygen species (ROS). Thus the utilization of NO by O2- will be minimum in this combination therapy. The regulatory role of NRF-2 in regulation to Antioxidant Response Element (ARE) mediated cytoprotective gene expression in BAC remains unexplored. The present review summarizes the role of NRF-2 mediated antioxidant response on the synergistic antitumor effect of L-Arginine and 5-FU in BAC. This review brought new insight into the management of BAC and in the same context, a hypothesis is raised on the use of reduced glutathione (GSH) or N-Acetyl Cysteine as it may be an added adjuvant in the combination of 5- FU and L-Arginine for management of BAC.