The effects of YSL plus low-dose doxorubicin on tumor growth in nude mice bearing human hepatocellular carcinoma BEL-7402 tumors. BEL-7402 cell (1 × 107/every mouse) was subcutaneously inoculated into the right back of every nude mouse. When the tumors had reached an average volume of 100 mm3, the tumor-bearing nude mice were randomly divided into different groups (n = 12). The mice were administrated i.p. 60 days. At the next day of the last administration, tumor tissue were stripped and three diameter which were vertical each other were measured. The tumor volume was calculated by V (cm3) = (1/6)π ABC, and A, B, C was three diameter of tumor. Then we weigh the tumor and calculated the tumor inhibition rate by tumor inhibition rate= (average weight of control group-average weight of experimental group)/average weight of control group × 100%. All data were analyzed by one-way analysis of variance using SPSS. The difference between two groups was analyzed by the Student-Newman-Keuls test. Standard deviation was represented by error line. *P < 0.05 as compared to the saline group. ADM, doxorubicin or adriamycin; YSL, tripeptide tyroserleutide.