Sea Anemone Heteractis magnifica Toxin Hct-S3 Suppresses the Migration of Solid Ehrlich Adenocarcinoma Cells Inoculated into BALB/C Mice

Malignant tumors represent a serious problem for humanity due to their widespread distribution and severe posttherapeutic consequences. The formation of metastases is the main criterion for tumor malignancy. A search for new compounds with antimetastatic activity remains an urgent problem. In this work, the antitumor activity of a cytolytic toxin Hct-S3 оf the sea anemone Heteractis magnifica was studied in an in vivo model of solid Ehrlich adenocarcinoma. It was established that intraperitoneal administration of Hct-S3 at doses of 0.01 and 0.02 mg/kg has hardly any effect on the tumor growth rate but prevents its metastasis from the primary tumor localization to other tissues. A significant decrease in the proliferative capacity of tumor cells was observed in the groups of mice treated with 0.01 and 0.02 mg/kg Hct-S3: the area of the tumor fluorescence zone decreased by 40 and 48%, and the index of integrated fluorescence density increased by 134 and 146%, respectively, as compared with animals without therapy. The obtained results confirm a high antiproliferative and antimetastatic potential of Hct-S3, which allows it to be considered as a promising compound for creating antitumor drugs.