ObjectiveTo investigate the inhibitory effect of the inhibition of antigen-presentation attenuators (iAPA)-based dendritic cells (DC) and cytotoxic T lymphocytes (CTL)-iAPA-DC/CTL on SMMC-7721 xenograft in nude mice. MethodsUsing the human hepatic carcinoma cell line SMMC-7721 on nude mice to establish a transplanted tumor model of human hepatocellular carcinoma (HCC).Twelve nude mice were divided into two groups randomly: normal saline control group (control group) and iAPA-DC/CTL group (n=6, each).After four times treatment with iAPA-DC/CTL (once a week), all mice were sacrificed.Tumor growth was calculated by measuring the long/short diameters and the tumor growth curve was delineated.The tumors were weighed and the tumor inhibition rate was calculated.In addition, the histopathological examination was conducted. ResultsThe SMMC-7721 xenograft model was successfully established in 85.71% (12/14) of all mice.The tumor volume was (3 661.48±322.59) mm3 and (2 725.36±252.65) mm3 in control group and iAPA-DC/CTL group, respectively.The tumor growth was significantly inhibited in iAPA-DC/CTL group (t=5.62, P < 0.05).The tumor weight was (1.97±0.21) g and (1.38±0.14) g in control group and iAPA-DC/CTL group, respectively.The tumor weight in iAPA-DC/CTL group was significantly reduced (t=5.73, P < 0.05), and the tumor inhibition rate was 29.95%.After immunohistochemical staining T lymphocyte counts was 0 cell/HPF and (54.24±4.31) cells/HPF in control group and iAPA-DC/CTL group, respectively.The number of T lymphocytes in iAPA-DC/CTL group was significantly increased (t=25.02, P < 0.05). ConclusioniAPA-DC/CTL could effectively inhibit the growth of subcutaneously implanted HCC.