LncRNA SSTR5-AS1 Predicts Poor Prognosis and Contributes to the Progression of Esophageal Cancer.

Abstract

Esophageal cancer (ESCA), as a common cancer worldwide, is a main cause of cancer-related mortality. Long noncoding RNAs (lncRNAs) have been shown in an increasing number of studies to be capable of playing an important regulatory function in human malignancies. Our study is aimed at delving into the prognostic value and potential function of lncRNA SSTR5-AS1 (SSTR5-AS1) in ESCA. The gene expression data of 182 ESCA samples from TCGA and 653 nontumor specimens from GTEx. The expressions of SSTR5-AS1 were analyzed. We investigated whether there was a correlation between the expression of SSTR5-AS1 and the clinical aspects of ESCA. In order to compare survival curves, the Kaplan-Meier method together with the log-rank test was utilized. The univariate and multivariate Cox regression models were used to analyze the data in order to determine the SSTR5-AS1 expression's significance as a prognostic factor in ESCA patients. In order to investigate the level of SSTR5-AS1 expression in ESCA cells, RT-PCR was utilized. CCK-8 trials served as a model for the loss-of-function tests. In this study, we found that the expressions of SSTR5-AS1 were increased in ESCA specimens compared with nontumor specimens. According to the ROC assays, high SSTR5-AS1 expression had an AUC value of 0.7812 (95% CI: 0.7406 to 0.8217) for ESCA. Patients who had a high level of SSTR5-AS1 expression had a lower overall survival rate than those who had a low level of SSTR5-AS1 expression. In addition, multivariate analysis suggested that SSTR5-AS1 was an independent predictor of overall survival for ESCA patients. Moreover, RT-PCR experiments indicated that SSTR5-AS1 expression was distinctly increased in three ESCA cells compared with HET1A cells. CCK-8 experiments indicated that silence of SSTR5-AS1 distinctly inhibited the proliferation of ESCA cells. Overall, ESCA patients with elevated SSTR5-AS1 had a worse chance of survival, suggesting it could be used as a prognostic and diagnostic biomarker for ESCA.