CONSIDERATIONS FOR THE USE OF CYTOKINE-SECRETING TUMOR-CELL PREPARATIONS FOR CANCER-TREATMENT

Limited efficacy of chemotherapy in most solid tumors has revived inte rest in immunotherapeutic approaches for cancer. One novel form of imm unotherapy is the use of cancer vaccines consisting of tumor cells gen etically engineered to secrete cytokines. The rationale for this immun ization strategy is based on the existence of tumor-specific antigens, on the importance of the cellular arm of the immune system in mediati ng an effective antitumor response, and on the role of cytokines in re gulating the cellular immune response. Such tumor vaccines showed cons iderable promise in various animal models and induced potent antitumor immunity in the host, which led to regression of established tumors a nd, moreover, produced immunological memory protecting animals from a subsequent tumor challenge at a distant site. Translated to the human patient, this implies that genetically modified tumor vaccines may be able to eradicate or reduce existing tumor deposits to subclinical lev els as well as provide long-term protection from regrowth of tumor cel ls. This report will review and discuss the concept and rationale for the use of cytokine-secreting tumor vaccines for the treatment of huma n malignancies.