Recurrent deletions of the TNFSF7 and TNFSF9 genes in 19p13.3 in diffuse large B-cell and Burkitt lymphomas.

A single nucleotide polymorphism-chip analysis of 98 cases of aggressive B-cell lymphomas revealed a recurrent deletion at 19p13 in nine of the cases. Six further cases with deletions encompassing this region were found in array-comparative genomic hybridization data of 295 aggressive B-cell lymphomas from a previous study. Three cases even showed a homozygous deletion, suggesting a tumor suppressor gene in the deleted region. Two genes encoding members of the tumor necrosis factor superfamily (TNFSF) were located in the minimally deleted region, that is, TNFSF7 and TNFSF9. As no mutations were found within the coding exons of the remaining alleles in the lymphomas with heterozygous deletions, we speculate that the deletions may mostly function through a haploinsufficiency mechanism. The cases with deletions encompassed both diffuse large B-cell lymphomas and Burkitt lymphomas, and a deletion was also found in a Hodgkin lymphoma cell line. Thus, TNFSF7 and TNFSF9 deletions are recurrent genetic lesions in multiple types of human lymphomas.