In our current study, which seeks to determine the clinical significance and functions of dysregulated lncRNAs in gastric carcinogenesis, we investigated lncRNA GAS5 (Growth Arrest-Specific Transcript 5), which was previously shown to be consistently downregulated and identified as a tumor-suppressor lncRNA in prostate cancer cells, renal cell carcinoma cells and breast cancer cells[19-21], though its functional significance has not yet been established. The gene discussed is GAS5; the disease is breast cancer.