ABSTRACT
<p><b>BACKGROUND</b>Overexpression of breast cancer-specific gene 1 (SNCG) is associated with poor prognosis in advanced breast cancer patients. This study aimed to determine the effects of SNCG knockdown in breast cancer cells by using small hairpin RNA (shRNA).</p><p><b>METHODS</b>Four different SNCG shRNA oligonucleotides were designed and chemically synthesized to construct mammalian expression vectors. These vectors were then stably transfected into a breast cancer MCF-7 cell line to knockdown SNCG expression. After SNCG knockdown was confirmed, the stable cell lines were inoculated into nude mice. SNCG mRNA and protein expressions were analyzed by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry, respectively in both the stable cell lines and xenografts.</p><p><b>RESULTS</b>All four SNCG shRNA constructs significantly reduced SNCG mRNA and protein levels in MCF-7 cells, as compared to the unrelated sequence control shRNA and the liposome control mice (P < 0.05). SNCG-knockdown MCF-7 cells formed significantly smaller tumor masses than cells expressing the unrelated sequence control or the liposome control mice (P < 0.05).</p><p><b>CONCLUSION</b>SNCG shRNA effectively suppressed breast cancer cell formation in vivo and may be a useful clinical strategy to control breast cancer.</p>