Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 14 6 2015 11 29 605 614 EN Zohreh Safari Department of Animal Biology, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran AND Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran Reza Safaralizadeh Department of Animal Biology, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran Mir Hadi Seyedzadeh Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran Ayla Valinezad Orang Department of Animal Biology, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran Ahad Zare Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran Mohammad Ali Hosseinpour Feizi Department of Animal Biology, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran Gholam Ali Kardar Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran AND Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran 2015 10 20 2015 10 20 It is aimed to evaluate the actual anti-cancerous effects of metformin on cancer cells in hypoxic condition. Non-cancerous cells (HEK293) and cancer cells (MCF-7) were cultured in both hypoxia and normoxia conditions and treated with different concentrations of metformin. The proliferation, apoptosis, and necrosis rate were assessed using MTT test and Annexin V assay. The S6K1 phosphorylation was assessed using western blotting. Zymography was used to measure the activity of metalloproteinase-9 (MMP-9). Metformin treatment inhibited proliferation of cancer cells in the optimal concentration of 10 mM under hypoxia condition, while it showed no effects on non-cancerous cell viability. The statistical analysis of MTT assay indicated that the pro-apoptotic function of metformin for cancer cells under hypoxia condition compared to normoxia was significant with different metformin concentrations (p<0.01). However, the effect of metformin treatments for non-cancerous cells under hypoxia condition compared to normoxia was not significant. Western-blot analysis indicated a significant decrease in S6K1 phosphorylation in cancer cells under hypoxia condition (p<0.05). Nevertheless, there was no considerable difference between normoxia and hypoxia conditions in non-cancerous cells. MMP-9 zymography analysis revealed that the highest inhibition of MMP-9 activity was observed in hypoxia condition by 20mM of metformin concentration only in cancer cell. The results indicate that in hypoxia condition metformin exerts its anti-cancerous function by inhibiting proliferation and tumor progression and inducing cell apoptosis more effectively than normoxia condition. In line with cancer cell conditions, most importantly hypoxic condition, metformin can be considered as a potential anti-cancerous drug. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/614 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/614/580