title: PAX5 deletion is common and concurrently occurs with CDKN2A deletion in B-lineage acute lymphoblastic leukemia.
abstract: The PAX5 is essential in normal B-cell lymphopoiesis and deregulation of PAX5 function is believed to contribute to leukemogenesis in B-ALL. We performed a comprehensive study using FISH, G-banding and IHC to identify PAX5 deletion and expression in 102 CD19+ clinical B-ALL cases (79 children and 33 adults) and investigated its relationship with common cytogenetic changes including BCR-ABL1, ETV6-RUNX1 and MLL rearrangements, and CDKN2A deletion. The incidences of translocations and deletions were 2.5% and 10.0% in children, and 0.0% and 18.2% in adults, respectively. The incidence of PAX5 deletion was higher than those of BCR-ABL1 (8.9%) or MLL rearrangements (5.1%) in children and than that of MLL rearrangement (3.1%) in adults. Most patients with PAX5 deletion (83.3% of children and 100.0% of adults with PAX5 deletion) had concurrent CDKN2A deletion. PAX5 deletions were detected both in patients with positive and negative PAX5 expression. In this study, we found that PAX5 is a common target in leukemogenesis of B-ALL along with CDKN2A. Owing to its frequent deletion in B-ALL, PAX5 could be used as one of the molecular markers in diagnosis and monitoring of the disease. No correlation between expression of PAX5 and deletion of PAX5 suggests allele-specific regulation.
authors.affiliation: Department of Laboratory Medicine, Seoul National University Hospital, Seoul, South Korea.
authors.forename: Miyoung
authors.initials: M
authors.lastname: Kim
authors.forename: Jung Eun
authors.initials: JE
authors.lastname: Choi
authors.forename: Cha Ja
authors.initials: CJ
authors.lastname: She
authors.forename: Sang Mee
authors.initials: SM
authors.lastname: Hwang
authors.forename: Hee Young
authors.initials: HY
authors.lastname: Shin
authors.forename: Hyo Seop
authors.initials: HS
authors.lastname: Ahn
authors.forename: Sung-Soo
authors.initials: SS
authors.lastname: Yoon
authors.forename: Byoung Kook
authors.initials: BK
authors.lastname: Kim
authors.forename: Myoung Hee
authors.initials: MH
authors.lastname: Park
authors.forename: Dong Soon
authors.initials: DS
authors.lastname: Lee
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D002871:Chromosome Banding; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000235:genetics*; D005260:Female; D017353:Gene Deletion; D015973:Gene Expression Regulation, Leukemic / Q000235:genetics; D015321:Gene Rearrangement / Q000235:genetics; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007223:Infant; D008297:Male; D008875:Middle Aged; D051757:PAX5 Transcription Factor / Q000235:genetics*; D015452:Precursor B-Cell Lymphoblastic Leukemia-Lymphoma / Q000175:diagnosis / Q000235:genetics*; D011379:Prognosis; D014178:Translocation, Genetic / Q000235:genetics; D055815:Young Adult
chemical_list: D019941:Cyclin-Dependent Kinase Inhibitor p16; D051757:PAX5 Transcription Factor; C497281:PAX5 protein, human