Expression assessment of a panel of long non-coding RNAs in gastric malignancy

Long non-coding RNAs (lncRNAs) have several important functions in the regulation of cell homeostasis and cell fate. Consequently, abnormal transcription of lncRNAs has been correlated with malignant transformation of cells. These human transcripts have been shown to participate in the progression of gastric cancer. In the current project, we evaluated expression of a panel of lncRNAs including HULC, MALAT1, FAS-AS1, GAS5, PVT1, OIP5-AS1 and THRIL in 30 gastric cancer tissues and paired adjacent non-cancerous tissues (ANCTs) using quantitative real-time PCR. HULC, OIP5-AS1 and THRIL transcription quantities were significantly lower in gastric tumors compared to ANCTs (P values = .02, 0.02 and 0.007, respectively). Relative transcription quantities of HULC, MALAT1, OIP5-AS1, PVT1, FAS-AS1 and THRIL were associated with the site of the primary tumor (P values = .002, 0.003, 0.002, 0.002, 0.002, and 0.001, respectively). Moreover, relative expression levels of PVT1 were associated with history of smoking (P value = .04). Correlations were identified between transcript quantities of these lncRNAs in both tumor samples and ANCTs. Receiver operating characteristic curve assessment demonstrated that THRIL had the highest diagnostic power among the mentioned lncRNAs (area under curve (AUC) = 0.72, P value = .001). HULC and OIP5-AS1 ranked afterwards (AUC values of 0.69 and 0.68; P values = .005 and 0.007, respectively). The current investigation underscores the dysregulation of these transcripts in gastric cancer specimens and suggests a number of these transcripts for further assessments of their suitability as cancer biomarkers.