[Polyamines, polyamine antimetabolites and urogenital tumors. State of research and clinical results].

The polyamine metabolism is pathologically changed in tumor tissues, and especially putrescine and spermidine demonstrate abnormally high values in kidney, bladder, and prostate cancer. The inductive processes which activate the biosynthetic polyamine enzymes in cancer are completely unknown. Of therapeutic interest is the fact that increased enzyme activities through irreversible inhibitors become significantly reduced, which consequently slows the tumor growth. Experimental therapy, especially in transplantable bladder and prostate cancer, displayed a 50% tumor destruction. In clinical studies using inhibitors of the polyamine biosynthesis, the dose had to be significantly reduced because of expressed toxicity. Additional investigations which tried a combination of reversible and irreversible inhibitors proved a similar antitumor activity, but less severe side effects.