Correlations between Immunological Phenotype and Karyotype in Malignant Lymphoma1

We have correlated immunological characteristics and karyotypic abnormalities from lymphomas in 118 patients. T-lymphomas differed significantly from B- and non-B-, non-T-lymphomas in having more normal metaphases, trisomy 19, and breaks at 1q21, 2q21, 3q27, 4q21, and 17q21 (P ≦; 0.03). Non-T-lymphomas had breaks in 18q in one-half the cases, but only one of 11 T-lymphomas had such breaks (P = 0.02). Among B-lymphomas, specific chromosome abnormalities were associated with the type of immunoglobulin heavy but not light chain expressed. A break at 14q22 or q24 was associated with surface 5µ-immunoglobulin (P = 0.02); trisomy 22 or a break in 22q and a break at 2q32 was associated with surface γ-immunoglobulin (P <; 0.01); and trisomy 12 and a break at 2pl3 was associated with cytoplasmic γ-immunoglobulin (P <; 0.01). Among B-lymphomas, several cytogenetic abnormalities were associated (Ps 0.02) with expression of CD24 or CD9 surface antigens. Lack of CD24 was associated with breaks in 2p25, 5q, and 6q21; CD9 was associated with a break at 6ql5. Associations with a specific immunological phenotype were not identified for cytogenetic abnormalities involving a band to which genes encoding immunoglobulin or the T-cell receptor have been localized. Breaks were common at 14q32, the genomic site of the immunoglobulin heavy chain loci, in B-, non-B-, non-T-, and T-lymphomas. In T-lymphomas this may be because this is the site of the AKT1 oncogene. Breaks were uncommonly found at the light chain loci or the genomic sites encoding the T-cell receptor. However, the recurring breakpoints associated with T-lymphomas were commonly found on chromosomes to which genes coding for various T-cell antigens have recently been provisionally assigned. copyright.