Antiangiogenic Properties of Scorpion Venom: A Novel Approach in Colon Cancer Therapy

Colorectal cancer (CRC) induced angiogenesis is the most harmful stage in the tumor’s growth, and invasion. Scorpion venom (SV) is a natural source that has a promising approach for the development of new pharmaceuticals. The study aimed to evaluate the anti-angiogenesis efficacy of the scorpion Leiurus quinquestratus venom (LQV) and Androctonus bicolor venom (ABV). Sprague Dawley rats were divided into four groups: Group 1 (Gp 1) (n=10) as a control group. Gp 2, 3, and 4 (15/each) were subcutaneously (S.C.) injected with 1,2-dimethylhydrazine (DMH) (40 mg/kg/ week) for 4 weeks. Gp 2 served as the DMH-induced cancer group, Gp 3 and 4 were intraperitoneally (i.p.) injected with 1/20 LD50 of LQV or ABV for 19 wks. At the end of the experiment, the colon was analyzed for histopathology, immunohistochemistry of CD34, vascular endothelial growth factor (VEGF), and VEGF protein expression via enzyme-linked immunosorbent antibody (ELISA). Microvessel density (MVD) and VEGF expression were quantified. The histological data of the colon demonstrated aberrant microvessel size and quantity in DMH group. Conversely, LQV and ABV treatments reduced neoplasia. The IHC staining of CD34 showed a reduction in the MVD, from 37 ± 11.7 in the DMH group to 10 ± 3.5, and 20 ± 6.5 in LQV and ABV treated groups, respectively. VEGF expression was strong in the DMH group, becoming only moderately stained in LQV or ABV groups. Moreover, decreased expression in the colonic VEGF protein levels was reported. Collectively, LQV and ABV, have a distinctive anti-angiogenesis capacity against CRC.