Thiabendazole: a potential adjuvant in cancer therapy.

This set of experiments was designed to evaluate the effects of thiabendazole (TBZ), a relatively nontoxic thiazole derivative, on the delayed hypersensitivity response of normal mice, tumor-bearing mice, and mice immunosuppressed by radiation and chemotherapy. Normal mice treated with a single intraperitoneal injection (20 mg. per kilogram) of TBZ given on the day of challenge with 2,4 dinitrochlorobenzene (DNCB) had 41 percent greater swelling of the injected foot pad than did control animals. This increased immune reactivity could be transferred with spleen cells from TBZ-treated animals as well as with macrophages incubated in vitro with TBZ. Mice given sublethal radiation (450 r) had almost complete restoration of the delayed hypersensitivity response (90 percent of control) when treated with TBZ. The immunosuppressive effects of Adriamycin also could be reversed in a similar fashion. It is likely that the immune function of more than one population of spleen cells is amplified by TBZ treatment. The observed effects strongly suggest that thiabendazole may have a role as an adjunct in cancer therapy.