en علوم پزشکی Medical Sciences مقاله پژوهشی Original Research Article New natural substances obtained from scorpion venoms could be promising approaches for the treatment of cancers. Scorpion venom is a fully mixed compound that containing enzymes, non-enzymes, ions, and other organic compounds that induces apoptosis and necrosis in mammalian cells. In this study, the cytotoxicity effects, redox potential, and the ability of apoptosis induction of <em>Odontobuthus bidentatus</em> scorpion venom on MCF-7 cells were investigated. To do this, the MCF-7 cells were treated with the scorpion venom. MTT and neutral red assays was used to evaluate the cytotoxicity. Catalase, GSH and NO assays are used to determine the cells redox potential. Caspase-3 and cytochrome c release assays were exploited to investigate the apoptosis. The results of MTT and neutral red tests showed that <em>O. bidentatus</em> crude venom has cytotoxic effects on MCF-7 cells. Moreover, the results of catalase, GSH and NO assays showed that the crude venom could change the redox potential of MCF-7 cells, dose dependently which eventually lead to apoptosis. Also, the results of caspase-3 and the release of cytochrome c confirmed cell apoptosis. These results suggest that <em>O. bidentatus</em> venom is a suitable source of apoptosis-inducing compounds. Odontobuthus bidentatus scorpion venom, MCF-7 cell line, Redox potential, Apoptosis induction 28 35 http://modernmedlab.com/browse.php?a_code=A-10-73-7&slc_lang=en&sid=1 Hani Keshavarz Alikhani hani.keshavarz865@gmail.com 10031947532846001787 10031947532846001787 No Department of Biology, Razi University, Kermanshah, Iran. Jamil Zargan jazrgan@ihu.ac.ir 10031947532846001788 10031947532846001788 Yes Department of Biology, Imam Hossein University, Tehran, Iran. Ali Bidmeshkipour abidmeshki@razi.ac.ir 10031947532846001789 10031947532846001789 No Department of Biology, Razi University, Kermanshah, Iran. Ehsan Zamani meshkat110@chmail.ir 10031947532846001790 10031947532846001790 No Department of Biology, Isfahan University, Isfahan, Iran. Mohsen Mosavi smohsenmousavi71@gmail.com 10031947532846001791 10031947532846001791 No Department of Biology, Imam Hossein University, Tehran, Iran. Ahmad Heidari ag.heidari@gmail.com 10031947532846001792 10031947532846001792 No Department of Production Engineering and Plant Genetic, Faculty of Agriculture, University of Zanjan, Zanjan, Iran. Ashkan Hajinoormohammadi kpahaji@ihu.ac.ir 10031947532846001793 10031947532846001793 No Department of Biology, Imam Hossein University, Tehran, Iran.