title: Differences in T-cell-receptor gene rearrangement and transcription in nasal lymphomas of natural killer and T-cell types: implications on cellular origin.
abstract: Although nasal lymphomas showing midfacial destructive lesions had been classified as T-cell lymphomas, their exact cellular origin is still unclear. Although they usually express a restricted number of T-cell-related antigens, namely, CD2, CD43, and CD45RO, other pan-T or subset-T-lineage antigens, such as CD3 (membrane), CD5, CD4, CD8, and CD7, are frequently absent. Conversely, they often express a natural killer (NK) cell-associated antigen, CD56, but lack other mature NK markets. To study their cellular origin further, the authors analyzed T-cell receptor (TCR) gene transcription in three cases of nasal lymphomas and correlated the findings with the phenotype and gene rearrangement data. Two cases of nasal lymphomas with CD2+CD3(Leu4)-CD19-CD56+ phenotype were shown to express truncated 1.0-kb Tbeta and multiple unrearranged Tdelta transcripts with germline TCR beta, gamma, delta, and immunoglobulin heavy-chain joining region (JH) genes, consistent with NK cell lineage. In contrast, one case of nasal lymphoma with CD2+CD3(Leu4)+CD8+CD19-CD56+ phenotype expressed full-length Talpha, Tbeta, and Tgamma transcripts rearranged TCR beta, gamma, and deleted TCR delta genes, indicating T-lineage, These results support the view that nasal lymphomas can separated into NK-cell and T-cell neoplasms, based on differences genotypic characteristics. The possibility of these tumors being derived from a putative common precursor cell merits further investigation.
authors.affiliation: Department of Pathology, University of Hong Kong, Pokfulam, Hong Kong.
authors.forename: A K
authors.initials: AK
authors.lastname: Chiang
authors.forename: G
authors.initials: G
authors.lastname: Srivastava
authors.forename: P W
authors.initials: PW
authors.lastname: Lau
authors.forename: F C
authors.initials: FC
authors.lastname: Ho
mesh_terms: D015329:Gene Rearrangement, T-Lymphocyte; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology* / Q000473:pathology; D008223:Lymphoma / Q000235:genetics* / Q000276:immunology* / Q000473:pathology; D016399:Lymphoma, T-Cell / Q000235:genetics* / Q000276:immunology* / Q000473:pathology; D009669:Nose Neoplasms / Q000235:genetics* / Q000276:immunology* / Q000473:pathology; D010641:Phenotype; D011948:Receptors, Antigen, T-Cell / Q000235:genetics*; D014158:Transcription, Genetic
chemical_list: D011948:Receptors, Antigen, T-Cell