Effects of levamisole (NSC-177023) and tetramisole (NSC-102063) in experimental tumor systems.

Levamisole and tetramisole had no antitumor effect against the following transplantable syngeneic murine tumors: L1210 leukemia, P388 leukemia, B16 melanoma, Madison 109 lung tumor, and Lewis lung carcinoma. In the Lewis lung carcinoma system there was no effect on primary tumor growth, metastasis, or survival. Tetramisole had a variable effect on the growth of rhabdomyosarcomas and the survival of BALB/c mice following intramuscular inoculation of Moloney sarcoma virus. In two experiments treatment with tetramisole either prior to or following inoculation of Moloney sarcoma virus increased the number of mice with tumor regression as opposed to progressive tumor growth, incrneased the number of long-term survivors, and prolonged the lifespan of mice that died of tumor. In two further tests neither levamisole nor tetramisole had an effect in this system. In mice immunosuppressed with cyclophosphamide prior to virus inoculation, there was not effect of treatment with levamisole or tetramisole.