OBJECTIVETo investigate the effects of Scutellaria barbata extract (ESB) in suppressing tumor growth and modulating the immune functions in mice bearing tumors derived from hepatocarcinoma H22 cells.

METHODSFifty mice inoculated subcutaneously with H22 cells were equally divided into the model group, high-, moderate-, and low-dose ESB groups, and 5-Fu group, with corresponding treatments for 10 days. Another 10 mice with only saline injection served as the normal control group. The body weight, tumor mass, thymus index and spleen index of the mice were measured, and the lymphocyte proliferation activity, NK cell activity and interleukin-2 (IL-2) production by the splenocytes were detected.

RESULTSModerate- and high-dose ESB significantly suppressed the tumor growth with tumor inhibition rate of 28.68% and 36.98%, respectively. ESB treatment at moderate and high doses significantly increased the thymus index and spleen index (P < 0.01), which were decreased significantly in 5-Fu group. The lymphocyte proliferation activity, NK cell activity and IL-2 production by the splenocytes were significantly lower in the model group than in the normal group (P < 0.05). Compared with the model group, ESB at the high dose obviously increased the three indexes above mentioned. The NK cell activity was also significantly improved in moderate-dose ESB group (P < 0.05).

CONCLUSIONESB can suppress the growth of H22 implant tumor and enhance the immune function of the tumor-bearing mice.