A comparison between the expression of tumorigenic LncRNAs in circulating exosomes and the tumor tissue in patients with the nonsmall-cell lung carcinoma: promising findings as to the novel biomarkers

Abstract

Different types of lung cancer, such as nonsmall-cell lung carcinoma (NSCLC), show the specificexpression of long non-coding ribonucleic acids (LncRNAs). There is evidence showing the possiblecorrelation between the expression of LncRNAs in tumor tissues and plasma exosomes. The presentstudy aimed to evaluate the expression level of LncRNAs in NSCLC patients in the cancerous tissues andadjacent non-cancerous tissue and the circulating exosomes. The tumor and adjacent non-canceroustissue samples of 142 patients with NSCLC were collected. Extracellular vesicles were isolated by theultracentrifuge method, and the nanoparticle tracking and the flow cytometry analysis were performedto identify the exosome fraction. The relative expression of the five LncRNAs, including AFAP1-AS1,BANCR, ANRIL, CCAT1, and GAS5, between tumor tissue, adjacent non-cancerous tissue, and plasmaexosomes were evaluated by quantitative real-time RT-PCR. Among 142 NSCLC samples, the expressionof lncRNA-GAS5 in tumor tissue was correlated with lncRNA-ANRIL in tumor tissue (p=0.035, C=0.177),while the rest of the lncRNAs did not show a significant correlation in tumor tissue. Expression of thefive different lncRNAs did not show any correlation in normal tissue and exosome content. Among thefive lncRNAs, only lncRNA-BANCR expression in ANCT was correlated with the exosomal expression(p=0.027, C=0.186). In conclusion, the present research demonstrated that a panel consisting of these fivelncRNAs could be helpful in the diagnosis of NSCLC