Abstract: Objective To investigate the expression of lncRNA GASL1 in breast cancer and the effect of lncRNA GASL1 on proliferation and apoptosis of breast cancer. Methods RT-qPCR was used to measure the expression of lncRNA GASL1 in breast cancer tissue and cells. pcDNA3.1 plasmid and siRNA were used to over-express and knockdown the expression of lncRNA GASL1 respectively in MCF-7 cells, and then measured the proliferation through MTT method, caspase 3 Activity Assay Kit was used to measure the caspase 3 activity. Moreover, the protein levels of Bax and Bcl-2 were tested by Western-blot. Results Lower lncRNA GASL1 levels in breast cancer tissue and cells compared with paracancerous normal tissues and normal breast cell HBL-100, respectively (P＜0.05). Overexpression of lncRNA GASL1 inhibited MCF-7 proliferation and promoted apoptosis (P＜0.05), while knockdown of lncRNA GASL1 increased proliferation and suppressed apoptosis (P＜0.05). Conclusions The expression of lncRNA GASL1 is lower in breast cancer, which is involved in development of breast cancer through the regulation on breast cancer cell proliferation and apoptosis.

Key words: Breast cancer, lncRNA GASL1, MCF-7, proliferation, apoptosis