Antitumor effect of dicyclohexylammonium sulfate, a potent inhibitor of spermidine, synthase.

The antitumor effect of dicyclohexylammonium sulfate (DCHA), a potent inhibitor of spermidine synthase, was tested on mice inoculated with Ehrlich ascites carcinoma, Ehrlich solid carcinoma and solid sarcoma-180. DCHA prolonged the survival time of mice bearing Ehrlich ascites carcinoma at doses of 50 approximately 100 mg/kg/day X 5. For Ehrlich solid carcinoma and solid sarcoma-180 the tumor growth was suppressed significantly at doses of 2 approximately 50 mg/kg/day X 10. The spermidine concentration of the tumor cells was lowered, while the spermine concentration hardly changed. The depletion of spermidine in the tumor cells might be a cause of the suppression of tumor growth.