A methylnitrosourea antineoplastic antibiotic isolated from the bacterium Streptomyces achromogenes. Streptozocin alkylates DNA, forming inter-strand DNA cross-links and inhibiting DNA synthesis. Due to its glucose moiety, this agent is readily taken up by pancreatic beta cells, inducing diabetes mellitus at high concentrations. Unlike other nitrosoureas, streptozocin causes little myelosuppression. Check for active clinical trialsusing this agent. or An anticancer drug that belongs to the family of drugs called alkylating agents.