Glycyrrhetinic Acid Induces Apoptosis in Leukemic HL60 Cells Through Upregulating of CD95/ CD178

Acute leukemia is characterized by the accumulation of neoplastic cells in the bone marrow and peripheral blood. Currently, chemotherapy and differentiating agents have been used for the treatment of leukemia. Recently, plant extracts, either alone or in combination with chemo agents, have been proposed to be used for the treatment of cancers. The aim of the present research was to study the cytotoxicity and apoptosis effects of an active licorice-derived compound, glycyrrhetinic acid (GA), on human leukemic HL60 cells. HL60 cells were cultured in RPMI1640 containing 10% fetal bovine serum. Cells were treated with different doses of GA and their viability and proliferation were detected by dye exclusion and 3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) assays. Apoptosis induction and expression of CD95 and CD178 were analyzed by flow cytometry. We observed that GA decreases cell viability and suppresses cells proliferation in a dose- dependent manner. In addition, our flow cytometry data show that GA not only induces apoptosis in HL60 cells, but also upregulates both CD95 and CD178 expression on the cell surface of these cells in a dose-dependent manner. The combination of GA with cytotoxic drugs and differentiation agents requires further investigation.