OBJECTIVETo study the expression profile of microRNAs (miRNAs) in peripheral T cell lymphoma, not otherwise specified (PTCL-NOS) and to explore the underlying molecular characteristics.

METHODSTwenty-one cases of PTCL-NOS were enrolled into the study. The tumor presented either as nodal (15/21) or extranodal (6/21) disease. TaqMan low density array was used to assess the expression level of 754 miRNAs in six cases of PTCL-NOS and three control cases of reactive lymphoid hyperplasia. Prediction of target genes for significant and differential expression of miRNAs was carried out using Targetscan and miRanda software. Bioinformatics tools were employed for GO-Analysis and Pathway-Analysis of target genes. The expression patterns of the three miRNAs were further analyzed in the remaining 15 cases of PTCL-NOS and 10 cases of reactive lymphoid hyperplasia, using single tube Taqman miRNA assays.

RESULTSEight miRNAs showed statistically significant difference in expression between PTCL-NOS and reactive lymphoid hyperplasia. miR-886-3p, miR-511, miR-1291, miR-572, miR-27a-3p, miR-25-3p and miR-886-5p were significantly overexpressed in PTCL-NOS while miR-182-5p was significantly underexpressed (P < 0.05). Target gene prediction showed that 1646 candidate genes involved in the pathogenesis and progression of PTCL-NOS. Further GO and Pathway-Analyses found that these genes significantly focused on 63 GO terms and 61 pathways. The results of three miRNA qRT-PCR confirmed that miR-572 and miR-1291 expression in PTCL-NOS had statistical significance.

CONCLUSIONSEight miRNAs are aberrantly expressed in PTCL-NOS, which may be involved in molecular regulation during the development of PTCL-NOS. The underlying mechanism is also related to a number of target genes and signaling pathways.