Diagnostic and prognostic significance of long noncoding RNA SSTR5-AS1 in patients with gastric cancer.

OBJECTIVE Long noncoding RNAs (lncRNAs) display a functional effect on the pathogenesis of several diseases, including various tumors. Herein, we aimed to reveal the role of lncRNA somatostatin receptor 5 antisense RNA 1 (SSTR5-AS1) in gastric cancer (GC). PATIENTS AND METHODS qRT-PCR was utilized for testing the SSTR5-AS1 expression in 158 paired primary GC tissues and corresponding normal gastric specimens. Receiver operating characteristic (ROC) curves were established to determine the diagnostic values of overexpression of SSTR5-AS1 in GC. A chi-square test was performed to analyze the correlation between SSTR5-AS1 expressions and several clinicopathological features in GC patients. Kaplan-Meier survival curve was constructed to estimate the overall survival (OS) and disease-free survival (DFS). Multivariate analyses were conducted to examine the prognostic value of SSTR5-AS1. RESULTS We observed that SSTR5-AS1 expression was highly expressed in GC specimens compared with adjacent non-tumor specimens (p < 0.01). High SSTR5-AS1 expression was correlated with an advanced pathologic stage. The ROC curves showed that areas under the ROC curve (AUC) for SSTR5-AS1 is 0.8419. Moreover, high expression of SSTR5-AS1 was observed to be associated with distant metastasis (p = 0.021) and TNM stage (p = 0.042). Besides, survival analysis showed that GC patients with high SSTR5-AS1 expression suffered poorer OS (p = 0.020) and DFS (p = 0.0007). Multivariate assays demonstrated that increased expressions of SSTR5-AS1 could be an independent prognostic marker of OS and DFS of GC patients. CONCLUSIONS Our findings indicate that SSTR5-AS1 served as a promising novel prognostic biomarker for GC.