Arteether Exerts Antitumor Activity and Reduces CD4+CD25+FOXP3+ T-reg Cells in Vivo

Chemo-immunotherapy is one of the new achievements for treatment of cancer, by which the success of anti-cancer therapy can be increased. In vitro studies have been shown that Arteether (ARE) induces apoptosis in tumor cells, but not in normal cells. To investigate the cytotoxic and immunomodulatory properties of Arteether invivo and in-vitro. In this study, we used MTT assay for evaluation of cytotoxicity of Arteether on tumor cell line and Peripheral Blood Mononuclear Cells (PBMCs) from healthy individuals. Balb/c mice were subcutaneously transplanted with tumor tissue taken from Spontaneous Mouse Mammary Tumor (SMMT) bearing female mice. Arteether was administered to breast tumor-bearing Balb/c mice at a dose of 6mg/kg/day intraperitoneally. Tumor sizes, lymphocyte proliferation, cytokines production, and the percentage of splenic Treg cells were measured. We observed that ARE could reduce the cell growth of 4T1 cell line in a dose-dependent manner but it had no cytotoxic effect on the growth of peripheral blood lymphocytes. ARE administered intraperitoneally to tumor-bearing Balb/c mice could reduce the tumor growth rate and splenic T-reg cells. No difference in the IFN-γ, IL-10 and IL-4 production was observed between tumor antigen-stimulated splenocytes of mice treated with ARE and control mice. These results underscore antitumor properties of Arteether that may aid in development of more effective antitumor agents.