RESUMO
PURPOSE: Antitumor effect of granulocyte macrophage colony-stimulating factor (GM-CSF)- producing murine colon cancer cells was elucidated against intrahepatic challenge of parental cancer cells, which is clinically relevant tumor model. MATERIALS AND METHODS: Using a model of liver metastasis by intrahepatic challenge of CT-26 murine colon carcinoma cells to syngeneic BALB/c mice, GM-CSF producing cells were given as a intradermal vaccine either 14 days prior to hepatic challenge, or in animals with established tumors. Tumor volume and survival were determined. RESULTS: Animals receiving vaccination showed significant systemic protection against the hepatic challenge of parental tumor cells, and in animals with established hepatic tumors significant response was observed with some prolongation in survival. CONCLUSION: It is concluded that GM-CSF-producing autologous tumor vaccine was effective for the protection of host agaisnt the metastatic hepatic tumor model. Even though its efficacy against the established tumor was not as significant as in protection, GM-CSF producing autologous tumor vaccine can provide support for the specific immunotherapy for the metastatic liver cancer.