[Receptor-mediated cancer therapy--tumoricidal cytokines, adoptive therapy of LAK, TIL]

Three modes of receptor-mediated cancer therapy were reviewed presenting our own data. Employment of tumoricidal cytokines (IFN, TNF, LT) to this type of therapy has been expected to be the most promising approach. However, preclinical and clinical results so far obtained, revealed that they were useful only for the very limited diseases including renal cancer or some hematological malignancies. Second approach is to utilize growth factors conjugated with toxin or carzinostatin which are readily internalized into tumor cells. In this context, transferrin-neocarzinostatin was examined in our laboratory both in vitro and in vivo for its anticancer activity and was found to suppress tumor growth more significantly than neocarzinostatin alone on the basis of molar ratio. Thus this approach may be worthy to be clinically investigated. Adoptive therapy of lymphokine activated killer (LAK) or tumor infiltrating lymphocyte (TIL) may also be categorized into receptor mediated cancer treatment since both are activated by signals through IL-2 receptor. Although clinical evaluation is still on going, the therapy appears to be effective only when effector cells are administered locally to tumors.