Synergistic effects of Cassia fistula extract combination with cisplatin on the regulation of microRNA-145 and gene expression in colon cancer cell line SW480

Abstract

Abstract Background: Combination therapy is an effective strategy for inhibiting cancer cells and stimulating the apoptosis gene, so the potential synergistic effects of combining Cassia fistula extract with cisplatin chemotherapy used in clinical practice have been studied. Objective: The study aimed to investigate the anticancer effects of C. fistula extract in vitro as well as the precise molecular mechanisms. Materials and Methods: For 24 h, the human colon cancer cell line SW480 was given a variety of doses of cisplatin and plant extract, as well as cisplatin with various concentrations of C. fistula. MTT assay was used to assess the cytotoxicity of the cisplatin, plant extract, half maximal inhibitory concentration (IC50) of cisplatin with plant, and combination of cisplatin and plant against colon cancer cells. The expression of microRNA, BAX, and BCL2 was analyzed using real-time polymerase chain reaction (qPCR). Results: The results showed that C. fistula extract exhibited higher cytotoxicity against colon cancer cells compared with untreated cells and showed synergistic effects when combined with cisplatin (CDDP). Cassia fistula extract induced cell apoptosis via the intrinsic (Bax and Bcl-2) apoptotic pathways and regulated the level expression of microRNA-145. In the SW480 cell line of colon cancer studies, C. fistula extract suppressed tumor growth through the inhibition of proliferation and induction of apoptosis. Our results showed synergistic effects when combined with IC50 of CDDP with Cassia extract through increasing the level of gene expression of Bax and reduced level expression of Bcl2. Also the regulated expression of microRNA-145. Conclusion: This study indicated that the synergistic of C. fistula extract and cisplatin significantly induce apoptosis by regulating the microRNA-145 gene, which is related to Bax and Bcl2 expression. Therefore, C. fistula, according to its cytotoxic and apoptotic activities, might be considered as a novel finding for the treatment of colon cancer.