Cytotoxicity Effect of Shigella flexneri Fraction on Breast Cancer Cell as a New Compound for Cancer Therapy

Breast cancer is a major cause of death among women worldwide. Accordingly, conventional medical treatments using high levels of cytotoxic drugs have some side effects for patients. Different secondary metabolites and enzymes from Shigella are considered in this case. This research aimed to study the effect of Shigella flexneri lysate on the induction of cell death in breast cancer cell line. For this purpose, Shigella lysate was prepared at different concentrations. 4T1 breast cancer cells were treated with different concentrations of bacterial lysate and sediment. The cell death was evaluated by PI color and cell viability was also measured by MTT assay. Analysis of bacterial lysate (IC50 250 μg/ml) for 24 hours has shown the cytotoxic effect on 4T1 breast cancer cells. Moreover, the sediment of bacteria (IC50 500 μg /ml) for 24 hours has shown a cytotoxic effect on 4T1 breast cancer cells. The cell death was confirmed using PI staining. Additionally, the bacterial lysate has shown a direct toxic effect on breast cancer cells. This protein may be used as a new therapy for cancer in future.