[Effect of costus root oil in murine tumors].

Costus root oil is a new primary sensitizer for examination of the delayed cell-mediated immune system. Histologic findings of skin producing a positive reaction to costus root oil show accumulation of lymphoid cells. If the delayed hypersensitivity reaction caused by costus root oil were to be used as a means of aggregating lymphoid cells, these cells would attack cancer cells in a non-specific manner. In the present study, BALB/c mice were injected with 20% costus root oil. Fourteen days later, Meth-A tumor cells were transplanted subcutaneously, 3% costus root oil was injected around the transplanted tumor, and the effects on suppression of tumor growth were studied. The results indicated that the challenge of costus root oil had inhibited growth of the tumor in the sensitized group compared with the controls. It is anticipated that costus root oil will be quite promising as a non-specific agent for cancer immunotherapy.