Identification of key long non-coding RNAs in gastric adenocarcinoma.

BACKGROUND: Gastric cancer is the third leading cause of cancer-related deaths worldwide. OBJECTIVE: The present study aims to identify key long non-coding RNAs (lncRNAs) and their potential roles in the pathogenesis of gastric adenocarcinoma. METHODS: The lncRNA and mRNA expression profile between gastric adenocarcinoma and adjacent non-tumor tissues were obtained from The Cancer Genome Atlas (TCGA). Differentially expressed lncRNAs (DElncRNAs) and mRNAs (DEmRNAs) between gastric adenocarcinoma and adjacent non-tumor tissues were identified after bioinformatics analysis. DElncRNADEmRNA co-expression network and DElncRNA-nearby DEmRNA interaction network were constructed, respectively. Functional annotation for DEmRNAs interacted with DElncRNAs was performed. Receiver operating characteristic (ROC) analysis of selected DElncRNAs was conducted. RESULTS: Based on TCGA, the mRNA and lncRNA expression profiles of 375 gastric adenocarcinoma and 32 adjacent nontumor tissues were downloaded. A total of 1502 DEmRNAs and 928 DElncRNAs between gastric adenocarcinoma and adjacent non-tumor tissues were identified. HOXC-AS3 might involve with gastric adenocarcinoma by regulating a set of HOX genes (HOXC8, HOXC9, HOXC10, HOXC11, HOXC12 and HOXC13) with cis-effect. AC115619.1-APOA4/APOB and AP006216.2APOA1/APOA4 integrations might play roles in gastric adenocarcinoma through regulating pathways of Fat digestion and absorption and Vitamin digestion and absorption. Six lncRNAs including (HOTAIR, C20orf166-AS1, PGM5-AS1, HOXC-AS3, HOXC-AS2 and AC012531.1) have excellent diagnostic value for gastric adenocarcinoma. CONCLUSIONS: This study identifies key lncRNAs in gastric adenocarcinoma which provides clues for exploring the pathogenesis and developing potential biomarkers for gastric adenocarcinoma.