Introduction: Chronic Myelogenous Leukemia (CML) is a malignant disease. Different drugs have been suggested for the treatment of leukemia, but none of them has resulted in complete remission. Recently scorpion toxins have been reported to have anticancer activity on several cell lines. In the present study, the effects of Hemiscorpius Lepturus scorpion was evaluated on K-562 cell line as an experimental model of CML.

 Methods: In this experimental trial to determine IC50, K-562 cells were cultured in RPMI media with 10% Fetal Bovine Serum (FBS), and 1% penicillin/streptomycin. Then they were treated with different concentrations of Hemiscorpius lepturus scorpion venom (1.95-1000µg/ml). Cytotoxic effect of venom against K-562 cancer cells was evaluated by MTT method. The data was an alyzed by the Graph Pad Prism 6.

Results: After the treatment of K-562 cells with different concentrations of venom, the MTT assay determined the IC50 value of 62.5 µg/ml of scorpion venom. The results of this study indicated that the treatment of the K-562 cells with scorpion venom was time-dependent compared to the untreated cells.  Compared with untreated cells (control), survival rates of the cells after 48-hour treatment with concentrations of 125, 62.5 and 32.25 µg/ml were 40.69±1.12, 54.92±10.5 and 53.58±9.43 respectively.

Conclusion: According to results of the study, this venom can be considered as a potential drug candidate for further studies on inhibitor treatment for CML.