The Effect of Snail1 Gene Silencing by siRNA in Metastatic Breast Cancer Cell Lines

BACKGROUND Breast cancer is the most common diagnosed cancer among women in the world. Snail1 plays a role in the development of the invasive phenotypes of cancer, neural cell differentiation, cell division and apoptosis in tumor cells. Traces of snail1 in metastasis of breast cancer to bone are observed. The aim of this study was to investigate the effect of specific snail1 siRNAs on the proliferation, migration, induction of apoptosis and cell cycle arrest of MDA-MB-468 cells. METHODS In 2015, this experimental study was performed on the MDA-MB-468 cell lines in Immunology Research Center, Tabriz University of Medical Sciences. After the design and construction of siRNA, transfection was performed with transfection reagent. The expression levels of mRNA and protein were measured by qRT-PCR and western blot analysis, respectively. The survival of cells was determined by using MTT assay cells, apoptosis using Tunel assay, Cell migration using scratch assay, Cell cycle analysis by Propidium Iodide (PI) DNA staining method using flow cytometry on the MDA-MB-468. RESULTS Transfection with siRNA significantly suppressed the expression of snail1 gene in dose-dependent manner after 48 h (P<0.0001). Surprisingly, treatment with snail1 siRNA arrested cell cycle in S phases (P<0.0001). Moreover, siRNA transfection had effects on breast adenocarcinoma cells and inhibited the migration (P<0.0001), proliferation (P<0.0001) and induced apoptosis (P<0.0016). CONCLUSION The snail1 can be considered as a potent adjuvant in breast cancer therapy.