ANTITUMOR EFFECT OF SNAKE VENOMS

R. J. DA SILVA(1), D. FECCHIO(2), B. BARRAVIERA(1,3)

1 Center for the Study of Venoms and Venomous Animals - CEVAP-UNESP, State of São Paulo, Brazil; 2 Department of Pathology of the School of Medicine of Botucatu, State of São Paulo, Brazil, 3 Department of Tropical Diseases of the School of Medicine of Botucatu, State of São Paulo, Brazil.

ABSTRACT. The search for biological antitumor agents has been pursued for over half a century. Snake venom has been shown to possess a wide spectrum of biological activities. The objectives of the present review are to evaluate the existing controversies on this subject published in a number of papers and to propose probable explanations for the phenomena observed.  We reported our results obtained in a study, in which we evaluated the action of the venoms of Crotalus durissus terrificus and Bothrops jararaca on Ehrlich ascites tumor cells.  We noticed an important antitumor effect, mainly with Bothrops jararaca venom, as well as an increase in the functional activity of macrophages.  We also observed an increase in the number of mononuclear and polymorphonuclear cells with Bothrops jararaca venom. Considering these findings, we postulate that both Bothrops jararaca and Crotalus durissus terrificus venoms can act directly on tumor cells.  In addition, we propose an indirect mechanism, based on the stimulation of the inflammatory response, to inhibit tumor growth and to promote its rejection.

KEY WORDS: cancer, inflammation, venom, snakes, Crotalus durissus terrificus, Bothrops jararaca.

CORRESPONDENCE TO:

R. J. DA SILVA - Caixa Postal 577, CEP 18.618-000, Botucatu, São Paulo, Brasil. Email cevap@cevap.org.br