HT-29 암세포 이종이식으로 유발된 종양에 대한 18β-Glycyrrhetinic Acid의 치료효과

Therapeutic Effect of 18β-Glycyrrhetinic Acid on HT-29 Cancer Cell in a Murine Xenograft Model

In the present study, we determined the effect of 18β-glycyrrhetinic acid (18β-GA) in the mice model bearing xenografts of HT-29 human colon cancer cell line. Data from the cytotoxicity assay displayed that 18β-GA induced cell death in HT-29. The cytotoxicity was enhanced as the 18β-GA treatment was prolonged. In case of 72 hrs treatment, LD50 of 18β-GA was approximately 90 μM, and the efficacy at 100 μM of 18β-GA appeared to be equivalent to that of doxorubicin at 1 μM. Based on the in vitro data, we tested the anti-tumor effect of 18β-GA in thymic mice (Balb/c strain). Xenograft tumors were generated by subcutaneous injection of HT-29 (3×106 cells/mouse) to mice and the mice were treated intraperitoneally with 18β-GA (50 μg/time/mouse) every other day for 4 times. The tumor volumes were measured for a period of 14 days. Data displayed that the 18β-GA treatment reduced the tumor volumes (P < 0.05) as compared to control mice. However, this activity was demolished when athymic mice (Balb/c nu/nu) were used instead of thymic mice. This observation appeared that T lymphocyte played an important role in the anti-tumor activity. In conclusion, our results indicate that 18β-GA has anti-tumor activity in HT-29 tumor-bearing mice, which may be associated with T cells.