Decreased expression of long non-coding RNA WT1-AS promotes cell proliferation and invasion in gastric cancer.

Tumor recurrence and metastasis remain the major obstacles for the successful treatment of patients diagnosed with gastric cancer. In recent years, long non-coding RNAs (lncRNAs) have been considered as key regulators of tumor behavior. In this study, we investigated the expression and biological role of a newly-identified cancer-related lncRNA, WT1-AS. We found that WT1-AS expression was significantly down-regulated in tumor tissues compared to matched adjacent non-tumor tissues. The WT1-AS expression level was also associated with tumor size and the clinicopathological stage. Cell proliferation, migration, and invasion were inhibited, and the proportion of G0/G1 cells increased when WT1-AS was ectopically-expressed in gastric cancer cells. Furthermore, ectopic expression of WT1-AS was demonstrated to inhibit tumor growth and metastasis in vivo. Finally, we found that WT1-AS overexpression could decrease ERK protein phosphorylation. Our study indicates that WT1-AS is significantly down-regulated in gastric cancers and may be correlated with tumor progression.