Synergistic Effect of Zuo Jin Wan on DDP-Induced Apoptosis in Human Gastric Cancer SGC-7901/DDP Cells

A traditional Chinese medicine (TCM) formula, Zuo Jin Wan (ZJW), has been found as an anticancer drug in human cancer. In this study, we investigated the synergistic effect of ZJW extracts on DDP-induced apoptosis in human gastric cancer SGC-7901/DDP cells. Our results demonstrated that ZJW extracts could increase the sensitivity of SGC-7901/DDP cells to DDP by increasing the concentration of DDP in cytoplasm and enhance the proapoptosis of DDP by upregulating the JNK and Bax expression, downregulating the Bcl-2 expression, increasing the accumulation of Cytochrome C in cytoplasm, and promoting the activities of caspase-3 and caspase-9. In vivo, ZJW extracts enhanced the inhibiting effect of DDP on tumor growth in SGC-7901/DDP xenograft model and upregulated the expression of p-JNK and Bax but downregulated the Bcl-2 expression in xenograft tumors. In conclusion, in vitro and in vivo, ZJW extracts could enhance the proapoptotic effect of DDP by promoting the activation of JNK and the expression of Bcl-2, inhibiting the Bax expression, followed by increasing the release of Cytochrome C from mitochondria to cytoplasm, and finally activating the caspase cade reaction. Our results implied that ZJW might serve as a synergistic drug with chemotherapeutic drugs DDP in the treatment of gastric cancer.