Expression of lncRNAs in salivary gland malignancies

Abstract

Salivary gland tumors are heterogeneous group of complex neoplastic conditions. Expressions of long non-coding RNA (lncRNAs) have been altered in these malignancies. In the current investigation, we measured five cancer-related lncRNAs, namely TUG1, PANDA, NEAT1, GAS5 and FAS-AS1 in different subtypes of salivary gland tumors. Expression of NEAT1 was lower in total malignant tissues compared with pleomorphic adenoma (PA) samples (expression ratio = 0.29, P value = 0.05). Expression of GAS5 was lower in total tumor tissues compared with PA samples (expression ratio = 0.15, P value = 0.01), adenoid cystic carcinoma (AdCC) samples compared with PA samples (expression ratio = 0.17, P value = 0.04), and in salivary duct carcinoma (SDC) samples compared with PA samples (expression ratio = 0.0.06, P value = 0.03). Finally, expression of FAS-AS1 was lower in total tumor tissues compared with PA samples (expression ratio = 0.18, P value = 0.02), AdCC samples compared with PA samples (expression ratio = 0.12, P value = 0.043), and in SDC samples compared with PA samples (expression ratio = 0.05, P value = 0.01), but higher in PA samples compared with adjacent non-cancerous samples (expression ratio = 7.3, P value = 0.05). Expression levels of PANDA and NEAT1 have been associated with tumor size (P values = 0.03 and 0.05, respectively). For NEAT1, expression levels had an increasing trend as the tumor size increased. Area under receiver operating characteristic curve values were 0.79 and 0.77 for GAS5 and FAS-AS1, respectively. Combination of GAS5 and FAS-AS1 increased AUC value to 0.80. The current study shows that dysregulation of lncRNAs might be used as diagnostic markers for salivary gland tumors.