Combination of Sodium Cantharidinate with Cisplatin Synergistically Hampers Growth of Cervical Cancer

BACKGROUND: Sodium cantharidinate (SC) has been broadly applied in lung cancer treatment in China, while its specific function in cervical cancer (CC), a great contributor to death of female reproductive system cancers, remains unclear. Our research evaluated the anti-tumor effects of SC in CC and the mechanism involved. METHODS: First, cisplatin (DDP)-resistant Caski-1 and ME180 cell lines were developed and treated with SC. The effects of SC on CC cell growth were then evaluated. Subsequently, the genes targeted by SC were predicted via the bioinformatics website. The correlations between PTPN1 expression and tumor stage, lymph node metastasis and tumor differentiation were examined. We further conducted rescue experiments by overexpressing PTPN1 in CC cells, followed by SC and cisplatin treatments. The activation of the PI3K/AKT pathway in CC cells, and the effect of SC on the growth and drug resistance of Caski-1 cells in vivo were investigated. RESULTS: The sensitivity of Caski-1 and ME180 cells to DDP was increased after SC treatment, which also enhanced the inhibitory effect of DDP on the cell growth. By prediction, we found that SC could target PTPN1. Patients with high expression of PTPN1 had higher clinical stage, lymph node metastasis and lower tumor differentiation. SC inhibited PTPN1 expression. Overexpression of PTPN1 attenuated the effect of SC. Furthermore, PTPN1 activated the PI3K/AKT pathway. Moreover, SC treatment inhibited the growth and drug resistance of Caski-1 cells in vivo. CONCLUSION: SC promotes drug sensitivity of CC cells to DDP by targeting PTPN1, thereby impairing the PI3K/AKT pathway.