Objective: To observe the inhibitory effect of dendritic cells (DCs) activated cytotoxicity T lymphocyte (CTL) combined with MAGE-1 nonapeptide on transplanted human hepatocyte carcinoma (HCC) in nude mice.
Methods: A model of HCC transplanted tumor was established by injecting BEL-7402 cell line HCC cells subcutaneously on the back of nude mice. Successful transplantation rate was 73%. Specific CTLs (1 x 10(6)), which were activated by DCs combined with MAGE-1 nonapeptide, were injected into the site of transplanted tumor (group A, n = 5). Another group of 17 mice were treated with same amounts of different kinds of cells, and they were divided into groups B, C, D, E, and F. The growth of tumor was observed, and pathological examination was also done.
Results: (1) The activated lymphocytes induced by DCs combined with MAGE-1 nonapeptide could suppress the growth of tumor and reduce the tumor size. In group A, 5/5 mice survived for at least two weeks, while the tumors grew rapidly and the majority of the mice died within two weeks in other groups (groups B, C, D, E, F) (P < 0.01). (2) Extensive necrosis and apoptosis were found in transplanted tumors in group A.
Conclusions: The DCs combined with MAGE-1 nonapeptide could not only inhibit the growth of HCC, but also result in produce death and apoptosis of HCC, hence preventing tumor metastasis and recurrence. The mechanism underlying tumor immunization resulted from DCs might be enhanced in apoptosis of tumor cells. MAGE-1 nonapeptide combined with DCs might be a potential novel tumor vaccine for the treatment of HCC.