Biotoxins in Cancer Therapy

The search for biological antitumor agents has been pursued for over half a century. Among the biological agents which have antitumoral activity, snake and scorpion venoms have been shown to possess a wide spectrum of biological activities. Venom components exhibit an antitumoral activity by means of direct cytolytic and cytostatic effects or indirect mechanisms such as amplifying of immune response against cancerous cells. These peptides constitute a potent antitumoral activity throughout their thrapeutic usages while they cause any significant side effects. Therefore it has been emphasized that natural venom peptides or their synthetic analogues will be valuable agents in replacement of classical antineoplastic drugs in cancer therapy in the future.