Combination of gallic acid and cisplatin inhibits esophageal cancer by downregulating COX-2
ZHANG Zhong-wei,LI Zhi-gang,LI Cai-xia
Abstract:
Objective This study aimed to understand whether (Gallic acid, GA) and DDP could generate a synergistic antitumor effect on ESCC cells. Methods Human esophageal carcinoma cell KYSE150 cells were subcutaneously injected into the mice. When the tumor grew to about 5-7 mm in diameter, the nude mice were randomly divided into control group, GA group, DDP group and combined group. The body weight and tumor volume were measured once a week. Nude mice were sacrificed 4 weeks after injection，and the tumor tissues and serum were collected. The expression of COX-2 and its derivative PGE2 were detected by RT-qPCR, Western blot and ELISA. In vitro, esophageal cancer cell lines EC9706 and KYSE150 were treated with GA, DDP and the combined group for 24 h and 48 h. Cell viability were detected by MTT assay; The expression of COX-2 and PGE2 were detected by RT-qPCR, Western blot and ELISA. Results Compared with the control group, the body weight of each treatment group was increased during feeding, but there was no significantly difference. The tumor volume of GA group, DDP group and combined group were all significantly lower than that of control group, and the expression of COX-2 in esophageal cancer tissues and the content of PGE2 in serum were significantly decreased (P<0.05). Among these, the combination induced the most significant difference compared to the GA or DDP alone (P<0.05). In vitro, GA and DDP are demonstrated to restrain ESCC cell proliferation in a time- and dose-dependent mode. GA and DDP could significantly reduce the expression of COX-2 and the content of PGE2 in the supernatant (P<0.05). The inhibition was more pronounced in the combined group compared to the GA or DDP alone (P<0.05). Conclusion GA combined with DDP has synergistic activity against esophageal cancer in vitro and in vivo, and may become a very promising clinical treatment strategy for esophageal cancer.
