Anaplastic large cell lymphoma with the t(2;5)(p23;q35) NPM/ALK chromosomal translocation and duplication of the short arm of the non-translocated chromosome 2 involving the full length of the ALK gene.
This report describes a case of anaplastic large cell lymphoma with the canonical t(2;5)(p23;q35) translocation in association with duplication of the short arm of the non-translocated chromosome 2, as demonstrated by two colour fluorescence in situ hybridisation. Because the tumour cells were tetraploid, these abnormalities were in duplicate, with four copies of the full length ALK gene and two copies of the t(2;5)(p23;q35) translocation. Despite multiple copies of the normal ALK gene, immunohistochemical, reverse transcriptase polymerase chain reaction, and western blot analysis demonstrated that only the fusion gene NPM/ALK was expressed and that normal ALK genes remained silent. Although based on a single case, these data indicate that structural rather than numerical abnormalities of the ALK gene are implicated in the pathogenesis of anaplastic large cell lymphomas.
Greenland
C
C
Department of Pathology and Groupe d'Etude des Lymphomes Malins CNRS/UPR2163 CHU Purpan, 31300 Toulouse, France.
Dastugue
N
N
Touriol
C
C
Lamant
L
L
Delsol
G
G
Brousset
P
P
D000077548:Anaplastic Lymphoma Kinase; D002648:Child; D002889:Chromosomes, Human, Pair 2; D002895:Chromosomes, Human, Pair 5; D020440:Gene Duplication; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D016403:Lymphoma, Large B-Cell, Diffuse / Q000235:genetics*; D008297:Male; D011505:Protein-Tyrosine Kinases / Q000235:genetics*; D020794:Receptor Protein-Tyrosine Kinases; D014178:Translocation, Genetic
C000626173:ALK protein, human; D000077548:Anaplastic Lymphoma Kinase; D011505:Protein-Tyrosine Kinases; D020794:Receptor Protein-Tyrosine Kinases