Upregulated expression of long noncoding RNA SNHG15 promotes cell proliferation and invasion through regulates MMP2/MMP9 in patients with GC.

Accumulation of data indicates that misregulated long noncoding RNAs (lncRNAs) are implicated in cancer tumorigenesis and progression and might be served as diagnosis and prognosis biomarker or potential therapeutic targets. Identification of cancer-associated lncRNAs and investigation of their biological functions and molecular mechanisms are significant for understanding the development and progression of cancer. In this study, we identified a novel lncRNA SNHG15, whose expression was upregulated in tumor tissues in 106 patients with gastric cancer (GC) compared with those in the adjacent normal tissues (P < 0.001). Furthermore, increased SNHG15 expression was positively correlated with invasion depth (P < 0.001), advanced tumor node metastasis (TNM) stage (P = 0.001), and lymph node metastasis (P = 0.019). SNHG15 levels were robust in differentiating GC tissues from controls (area under the curve (AUC) = 0.722; 95 % confidence interval (CI) = 0.657-0.782, P < 0.01). Kaplan-Meier analysis demonstrated that elevated SNHG15 expression contributed to poor overall survival (P < 0.01) and disease-free survival (P < 0.01) of patients. A multivariate survival analysis also indicated that SNHG15 could be an independent prognostic marker. Furthermore, knockdown of SNHG15 expression by siRNA could inhibit cell proliferation and invasion and induce apoptosis, while ectopic expression of SNHG15 promoted cell proliferation and invasion in GC cells partly via regulating MMP2 and MMP9 protein expression. Our findings present that elevated lncRNA SNHG15 could be identified as a poor prognostic biomarker in GC and regulate cell invasion.