The effect of the Substance P/NK1R system on thioredoxin and its target gene, miR-325-3p, in MCF-7 breast cancer cells

Abstract

Abstract Purpose Breast cancer (BC) is the most frequent malignancy with a high morbidity and mortality rate among women that can be initiated and be progressed through activating the neurokinin-1 receptor (NK1R) by substance P (SP), a highly conserved member of the tachykinin peptide family. The oxidative stress-mediated role of the SP/NK1R system results in BC pathogenesis is not entirely understood. Therefore, this study was designed to shed light on the link between SP/NK1R and cellular redox state in MCF-7 breast cancer cells. Methods Aprepitant IC50 was measured by resazurin assay. Reactive oxygen species were assessed utilizing DCFDA assay. Thioredoxin (Txn) and miR-325-3p genes expression were determined through Real-Time PCR. To evaluate the Txn protein expression, western blot analysis was performed. Results We found that SP elevated ROS production in these cells. furthermore, SP leads to a remarkable down-regulation of miR-325-3p and thioredoxin (Trx) target genes and protein expression of Trx in MCF-7 cells. In addition, aprepitant inhibited SP's effects; therefore, it decreased ROS accumulation, and up-regulated Trx and miR-325-3p genes, suggesting that aprepitant may render antioxidant properties through Trx. Conclusion Oxidative stress could have an essential role in BC pathogenesis via activating the NK1R by SP. SP can decrease the BC cell's antioxidative capacity by reducing the Trx gene and protein and miR-325-3p gene. Therefore, it causes an increase in ROS production and oxidative damage. the present investigation indicates that the SP/NK1R system might be an appealing and promising therapeutic target against BC.