Comparative genomic hybridization study of nasal-type NK/T-cell lymphoma

Background: Nasal-type NWT-cell lymphoma is a rare type of non-Hodgkin's ly mphoma, The genetic changes associated with pathogenesis have not been well defined, This study investigates the nonrandom genetic alteration of nasal -type NWT-cell lymphoma, Methods: Nine cases were studied, Comparative geno mic hybridization (CGH) was carried out using fresh tumor tissues of seven nasal-type NWT-cell lymphomas, To complement the data by CGH, loss of heter ozygosity (LOH) of chromosomes 6q, 1p, and 17p using polymorphic markers an d p53 gene mutation by polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) were analyzed. Results: The DNA copy number change s of seven nasal-type NWT-cell lymphomas were gains on chromosomes 2q(5), 1 3q(4), 10q(3), 21q(2), 3q(2), 5q(2), and 17q(2), and losses involving chrom osomes 1p(4), 17p(4), 12q(3), 13q(2), and 6q(1), One of six cases informati ve for at least two markers for chromosome 6q showed LOH at D6S300, D6S1639 , D6S261, D6S407, and D6S292, Two cases showing loss of 1p and 17q by CGH r evealed LOH at D1S214, D1S503, and D17S559. P53 mutation was detected in ex on 8 in one of nine cases, Conclusion: Frequent DNA losses at 1p, 17p, and 12q and gains at 2q, 13q, and 10q suggested that these regions could be tar gets for further molecular genetic analysis to investigate tumor suppressor genes or oncogenes associated with tumorigenesis of NWT-cell lymphoma. Inf requent alteration of 6q contrary to previous studies raises doubt about an implication of 6q loss in the pathogenesis of early-stage NWT-cell lymphom a, Further studies on more defined cases are required to verify their assoc iation. (C) 2001 Wiley-Liss, Inc.