Upregulation of T-Cell-Specific Transcription Factor Expression in Pediatric T-Cell Acute Lymphoblastic Leukemia (T-ALL)

• Published in: Turkish journal of haematology Vol. 29; no. 4; pp. 325 - 333
• Main Authors: Sayitoğlu, Müge, Erbilgin, Yücel, Hatırnaz Ng, Ozden, Yıldız, Inci, Celkan, Tiraje, Anak, Sema, Devecioğlu, Omer, Aydoğan, Gönül, Karaman, Serap, Sarper, Nazan, Timur, Cetin, Ure, Umit, Ozbek, Uğur
• Format: Journal Article
• Language: English
• Published: Turkey Galenos Publishing 01.12.2012; Galenos Publishing House
• Subjects: expression; pediatric; prognosis; t-all; transcription factor; Transcription factor; Expression; Pediatric; T-ALL; prognosis
• ISSN: 1300-7777; 1308-5263; 1308-5263
• DOI: 10.5505/tjh.2012.13540

T-cell acute lymphoblastic leukemia (T-ALL) is associated with recurrent chromosomal aberrations andabnormal ectopic gene expression during T-cell development. In order to gain insight into the pathogenesis of T-ALLthis study aimed to measure the level of expression of 7 T-cell oncogenes (LMO2, LYL1, TAL1, TLX1, TLX3, BMI1, andCALM-AF10) in pediatric T-ALL patients Material and Methods: LMO2, LYL1, TLX1, TLX3, BMI1, TAL1, and CALM-AF10 expression was measured usingquantitative real-time PCR in 43 pediatric T-ALL patients. A high level of expression of LMO2, LYL1, TAL1, and BMI1 genes was observed in a large group of T-ALL.Several gene expression signatures indicative of leukemic arrest at specific stages of normal thymocyte development(LYL1 and LMO2) were highly expressed during the cortical and mature stages of T-cell development. Furthermore,upregulated TAL1 and BMI1 expression was observed in all phenotypic subgroups. In all, 6 of the patients had TLX1and TLX3 proto-oncogene expression, which does not occur in normal cells, and none of the patients had CALM-AF10fusion gene transcription. Expression of LYL1 alone and LMO2-LYL1 co-expression were associated with mediastinalinvolvement; however, high-level oncogene expression was not predictive of outcome in the present pediatric T-ALLpatient group, but there was a trend towards a poor prognostic impact of TAL1 and/or LMO2 and/or LYL1 protooncogeneexpression. Poor prognostic impact of TAL1 and/or LMO2 and/or LYL1 proto-oncogene expression indicate the needfor extensive study on oncogenic rearrangement and immunophenotypic markers in T-ALL, and their relationship totreatment outcome. None declared.