Expression profile of long noncoding RNAs in human papillary thyroid carcinoma.

Long noncoding RNAs (lncRNAs) are strongly associated with cancer biology. The objective of this study was to investigate the expression profile of lncRNAs in human papillary thyroid carcinoma (PTC), and to understand the biological role of lncRNAs and their involvement in the oncogenesis of PTC. The lncRNAs and messenger RNAs (mRNAs) expression in human PTC and paired adjacent noncancerous thyroid (NCT) tissues were studied using microarray. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to validate five differentially expressed lncRNAs. We identified 2925 significantly differentially expressed lncRNAs (absolute fold change >2.0; P< 0.05) with potential roles in PTC, among which 1922 were up-regulated and 933 were down-regulated. The qRT-PCR results agreed with the microarray results. Gene ontology (GO) enrichment and pathway analysis were additionally used to investigate the gene function. Significantly enriched pathways among those mRNAs that were differentially expressed were identified. Many of these pathways were related to cancer, such as "pathways in cancer" (60 genes were associated) and "proteoglycans in cancer" (34 genes were associated). Co-expression network and target prediction analysis of lncRNAs showed that TCONS_00020457 might play important roles in PTC. The results of this study indicated that lncRNAs might be the important regulators in the tumorigenesis of PTC and lay the basis for understanding the function and mechanism of lncRNAs related to PTC.