Genetic rearrangements result in altered gene expression and novel fusion transcripts in Sézary syndrome

• Published in: Oncotarget Vol. 8; no. 24; pp. 39627 - 39639
• Main Authors: Iżykowska, Katarzyna, Przybylski, Grzegorz K, Gand, Claudia, Braun, Floriane C, Grabarczyk, Piotr, Kuss, Andreas W, Olek-Hrab, Karolina, Bastidas Torres, Armando N, Vermeer, Maarten H, Zoutman, Willem H, Tensen, Cornelis P, Schmidt, Christian A
• Format: Journal Article
• Language: English
• Published: United States Impact Journals LLC 13.06.2017
• Subjects: Adult; Aged; Aged, 80 and over; Case-Control Studies; Chromosomes, Human; DNA Copy Number Variations; Female; Follow-Up Studies; Gene Expression Regulation, Neoplastic; Gene Rearrangement; High-Throughput Nucleotide Sequencing; Humans; Male; Middle Aged; Oncogene Proteins, Fusion - genetics; Prognosis; Research Paper; Sezary Syndrome - genetics; Sezary Syndrome - pathology; Skin Neoplasms - genetics; Skin Neoplasms - pathology; NGS; Sézary syndrome; RNASeq; rearrangement; whole genome
• ISSN: 1949-2553; 1949-2553
• DOI: 10.18632/oncotarget.17383

Sézary syndrome (SS) is an aggressive, leukemic cutaneous T-cell lymphoma variant. Molecular pathogenesis of SS is still unclear despite many studies on genetic alterations, gene expression and epigenetic regulations. Through whole genome and transcriptome next generation sequencing nine Sézary syndrome patients were analyzed in terms of copy number variations and rearrangements affecting gene expression. Recurrent copy number variations were detected within 8q (MYC, TOX), 17p (TP53, NCOR1), 10q (PTEN, FAS), 2p (DNMT3A), 11q (USP28), 9p (CAAP1), but no recurrent rearrangements were identified. However, expression of five genes involved in rearrangements (TMEM244, EHD1, MTMR2, RNF123 and TOX) was altered in all patients. Fifteen rearrangements detected in Sézary syndrome patients and SeAx resulted in an expression of new fusion transcripts, nine of them were in frame (EHD1-CAPN12, TMEM66-BAIAP2, MBD4-PTPRC, PTPRC-CPN2, MYB-MBNL1, TFG-GPR128, MAP4K3-FIGLA, DCP1A-CCL27, MBNL1-KIAA2018) and five resulted in ectopic expression of fragments of genes not expressed in normal T-cells (BAIAP2, CPN2, GPR128, CAPN12, FIGLA). Our results not only underscored the genomic complexity of the Sézary cancer cell genome but also showed an unpreceded large variety of novel gene rearrangements resulting in fusions transcripts and ectopically expressed genes.