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Background & objectives: Cancer is the leading cause of death worldwide. In this study, the cytotoxic effect of hydroalcoholic extract of Colutea persica leaf and its synergic effect with doxorubicin were investigated on MCF-7, LNCaP and SKM (as control) cell lines.
Methods: Hydroalcoholic leaf extract of Colutea persica was prepared using maceration method and ethanol 70%. Breast cancer (MCF7), prostate (LNCaP) and fibroblast (SKM) cell lines were cultured in microplates (96 wells) and exposed to various concentrations (10, 7.5, 5, 2.5, 1.25, 0.625, 0.312 and 0.156 mg/ml) of plant extract and doxorubicin (20, 80, 320 and 640 nM) solution. The synergistic effect of 20 nanomol of drug and 0.156 mg / ml of the plant extract was investigated. MTT assay was employed to evaluate the cytotoxic effects of the extract on cell lines at different time intervals (24, 48 and 72 hours). Staining with annexin V and propidium iodide (PI) was used to identify different types of cell death either necrosis or apoptosis.
Results: The plant extracts had cytotoxic effect and cell viability rate was lower than fibroblasts. At different times, the concentration of 10 mg /ml of the extract showed the most growth inhibition of breast and prostate cell lines. The combination effect of plant extract with doxorubicin on cells was not significant (p<0.01). The Annexin V/PI flow cytometry results showed that the percentage of initial apoptosis, delayed apoptosis and necrosis in treated cells increased compared to untreated cell.
Conclusion: Hydroalcoholic extract of Colutea persica leaf inhibits the growth of cancer cells and induce apoptosis in breast and prostate cancer cells.