Anti-tumoral Effects of Crotalus Venom.

¹Soares, M.A.; ¹Pujatti, P.B. and ¹Gouvêa dos Santos R.

1 Lab. Radiobiologia, Centro de Desenvolvimento da Tecnologia Nuclear/CNEN, Belo Horizonte 

Patients with benign pituitary adenoma can have hypersecretion of growth hormone (GH). The long term hypersecretion of GH induces the development  of a debilitating disorder: acromegaly. Currently, gamma knife radiosurgery is predominantly used to treat failed pituitary surgery. However,  radiosurgery has the risk of  radiation damage to the visual pathways. Several snake venom toxins have been referred to inhibit cancer cell adhesion, migration, tumor growth and metastases induced in experimental mice models. In this study we examined  the anti-proliferative and cytotoxic effects of the venom of Crotalusdurissus terrificus on pituitary adenoma cells (GH3).

GH3 cells were treated with different concentrations of crotalic venom and gamma irradiation at doses ranging from 3 to 12 Gy.  Following treatments, monolayer cells acquired round shapes, detached and formed cells suspension. Cytotoxicity effect of the venom was remarkably increased at concentrations higher than 1mg/ml. This cytotoxicity was time dependent. Crotalic venom seems to have a metabolism stimulating effect in lower concentration and a slight cytotoxic effect at these concentrations. However, at the micromolar range the venom inhibited mitochondria metabolism, clonogenic proliferation, and increase cytotoxicity. Gamma irradiation toxicity was also observed at dose as low as 3Gy (almost 50% cytotoxicity after 24h). Proliferation rate was also decreased.

These results suggest the potential use of the components of crotalic venom in tumor therapy. Further studies are in development to verify the anti-tumoral effects of the components of this venom and the combined treatment with radiotherapy.

Support : FAPEMIG, CDTN, Probic-PUC/MG

Correspondence to: priscillapujatti@ig.com.br