Immunotherapy of tumor metastasis via gene therapy.

Active cellular immunotherapy of cancer, via gene-modified tumor cells, may develop to an effective treatment modality. Here we discuss some of the cytokines used in gene transfer, the importance of MHC class I expression on tumor cells used as vaccines, the relevance of experimental tumor systems to human tumors, and the use of live versus irradiated vaccines. Possible methods for effective gene transfer and possible protocols for immunotherapy studies are presented. Our studies in two highly metastatic murine tumors, the Lewis lung carcinoma (3LL) and the B16 melanoma, and immune mechanisms involved in immunotherapy of metastasis are summarized.