Background: The main types of thyroid neoplasms, follicular adenoma (FA), follicular thyroid carcinoma (FTC), classical and follicular variants of papillary carcinoma (clPTC and fvPTC), anaplastic thyroid carcinoma (ATC), are differ in the prognosis, rate of progression and metastatic behavior. It can be supposed that there are specific patterns of lncRNAs involved in the development of clinical and morphological features. The lncRNA landscapes within distinct benign and malignant histological variants of thyroid neoplasm are unknown.
Methods: Comprehensive set of Microarray and RNA-Seq datasets was analyzed for the expression of lncRNAs in FA, FTC, fvPTC, clPTC and ATC. The potential biological functions were evaluated via coexpression and enrichment analysis.
Results and conclusion: Abberant expression of lncRNA in FA, FTC, fvPTC, clPTC and ATC was established. The lncRNAs common for benign and malignant neoplasms, specific for papillary carcinomas, specific for clPTC, fvPTC and ATC are determined. The determined common and specific lncRNAs are found to be putatively involved into L1CAM interactions; processing of capped intron-containing pre-mRNA; Tryptophan metabolism; PCP/CE pathway and Beta-catenin independent WNT signaling; extracellular matrix organization and cell cycle and mitotic. The patterns of lncRNA expression in FA and FTC are appeared to be similar with no genes significantly differentially expressed within these subtypes. Previously known oncogenic and supressor lncRNAs (NR2F1-AS1, LINC00511, SLC26A4-AS1, CRNDE, LINC01116, RMST) are found aberrantly expressed in thyroid carcinomas. The findings enhance the understanding of lncRNA landscape in thyroid neoplasms and its role in thyroid cancer progression.