The effect of Oscillatoria sp. cyanobacterium extract on MCF-7 breast cancer cell line and CASP3 gene expression

Breast cancer is the most common cancer and the second leading cause of cancer death in women after lung cancer. Many efforts, including surgery, radiation and chemotherapy, have been made to treat breast cancer. Due to some drawbacks of chemotherapy such as toxicity and drug resistance, some other strategies, including use of marine resources, have recently been developed. Cyanobacteria have some effective compounds that can induce the process of cell death in cancer cells and might be promising candidate for cancer therapy. In the present study, the effect of hydro-alcoholic extract of Oscillatoria cyanobacterium on the viability and gene expression of caspase 3 (CASP3) in MCF-7 breast cancer cell line was examined. Breast cancer cell lines were treated with concentrations of 0.075, 0.15, 0.3, 0.6, 1.2, 2.5, 5 and 10 mg/mL of Oscillatoria extract. The effect of extracts on the viability of cells was evaluated by MTT assay and alteration of caspase 3 gene expression was checked out by Real Time PCR. The results showed that the MCF7 cell viability was reduced in the presence of increasing concentration of the extract with significant differences compared to the control samples. The results of Real Time PCR showed that the expression of caspase 3 significantly increased after 24 h in comparison with the control group.