Synergism of the combination of Rhopalurus junceus scorpion venom with conventional cytostatics in the ct26 tumor cell line.

Abstract

Introduction: The endemic scorpion venom of Cuba, Rhopalurus junceus (R. junceus), decreases the viability of tumor cells of epithelial origin and has no cytotoxic effect on normal cells. However, its antineoplastic effect on murine colon tumor cells and the type of pharmacological interaction of its combination with conventional chemotherapeutic agents used in the clinic for the treatment of colon cancer have not been evaluated. Objective: To determine the potentiality of the R. junceus scorpion venom to increase the cytotoxic effect of conventional cytostatics on colon tumor cells. Materials and methods: CT26 murine colon tumor cells were treated simultaneously at a constant rate of concentrations equal to or lower than the mean inhibitory concentration (IC50) of the venom of the scorpion R. junceus and the cytostatics: doxorubicin (DOX), cisplatin (CDPP) and paclitaxel (PTX), respectively. Cell viability was determined by the MTT assay, after 72 hours of incubation and the determination of apoptotic cell formation was determined by DAPI staining after 24 hours of combination with ½ of the IC50. The combination and dose reduction rate was determined by the Compusyn software. Results: The combination of venom with CPDX, PTX, and DOX, paclitaxel and doxorubicin significantly reduced the viability of the CT26 tumor line, compared to individual treatments. The type of drug interaction of said combination was synergistic at high concentrations. Individual treatment with ½ of the IC50 of R. junceus scorpion venom or with conventional cytostatics and the combination of each cytostatic with the venom induced morphological changes characteristic of cell death by apoptosis. Conclusion: R. junceus scorpion venom in combination with CDDP, PTX, and DOX paclitaxel, doxorubicin and cisplatin increases the cytotoxicity of these chemotherapeutic agents on colon tumor cells.