Chromosomes of malignant lymphomas. Studies in short-term cultures from lymph nodes of twenty cases

Recent results on the biology of Hodgkin and Reed-Sternberg cells. I. Biopsy material

The most recent sophisticated investigations have provided new and revealing, but also contradictory and controversial information on the biological nature and the cellular origin of Hodgkin and Reed-Sternberg cells (H-RS). Immunophenotypic analyses have shown variable phenotypic antigen expression; but, on balance the data suggest a lymphoid cell expressing T- and/or B-cell-associated markers and certain activation antigens while lacking immunological features of monocytes-macrophages or other lineages. Molecular genetic studies have demonstrated heterogenous findings with respect to rearrangements of T-cell receptor and immunoglobulin genes. Only a small percentage of the cases has rearrangements; this might be due to the threshold of sensitivity of the method combined with the scarcity of the malignant cells. Epstein-Barr virus (EBV) genomes are clonally integrated in the H-RS cells of about half the cases. The significance of these findings--whether EBV is a causative agent or an epiphenomenon--remains to be elucidated. H-RS cells express mRNA and proteins of various cytokines and cytokine receptors implying a predominant role for cytokines in the pathophysiology of HD. The mononuclear and polynuclear H-RS cells are capable of DNA synthesis and nuclear division; the lack of cellular division leads to multinuclearity through the process of endomitosis. Mutations and expression of only a limited number of oncogenes have been tested thus far. Whether the bcl-2 oncogene is involved in HD remains a matter of debate. Aneuploidy and non-random chromosomal abnormalities are the results of cytogenetic analyses of H-RS cells. However, no chromosomal marker specific for HD has yet been found. Thus, while studies of EBV involvement, growth factor production, oncogene expression and chromosomal abnormalities contributed a fair amount of new data on the nature of H-RS cells, only immunophenotyping and genotyping provided some indication of the cellular derivation: an activated lymphoid cell that possibly expresses oncogenes, that probably is infected with EBV, that most likely produces cytokines, that certainly has multiple karyotypic abnormalities.

Karyotypic abnormalities and immunoglobulin gene rearrangements in Hodgkin's disease

Biopsy samples from seven patients with Hodgkin's disease (HD) were examined for cytogenetic abnormalities and rearrangement of the genes encoding the immunoglobulin chains and T-cell receptor chains. Three samples demonstrated clonal rearrangements of both IgH and IgL genes. No rearrangements of the TCR beta genes were detected in any of the samples. Karyotypic abnormalities were also found but only in the three cases where a clonal rearrangement of the immunoglobulin genes was shown. Two of these three cases had multiple karyotypic abnormalities, with the remaining patient being trisomic for chromosome 16 as the sole abnormality. These results are discussed and compared with previous reports in the literature concerning HD.

Cytogenetic studies of Hodgkin's disease. Analysis of involved lymph nodes from 12 patients

Cytogenetic studies were performed on 12 involved lymph nodes from Hodgkin's disease patients utilizing conditioned medium from 12-O-tetradecanoylphorbol-13-acetate-staphylococcus enterotoxin A induced mononuclear cells. The majority of cells analyzed had a normal karyotype. An unusually high rate of nonclonal karyotypic abnormalities was noted in most cultures. Clonal abnormalities involving chromosomes 3 and 21 were noted in two patients. Cytogenetic analysis of cultures stimulated with conditioned medium or specific growth factors may lead to a better understanding of the genetic mechanisms involved in Hodgkin's disease.

Cytogenetic studies in Hodgkin's disease

Cytogenetic analysis was attempted in 20 patients with Hodgkin's disease. No mitoses were found in 2 cases, normal metaphases in 7, and normal metaphases with nonclonal aberrations in 7. Of the 4 cases with clonal aberrations, one had +16 as the sole change, whereas the remaining tumors had multiple numerical and structural changes.

Cytogenetic investigations in Hodgkin's disease: I. Involvement of specific chromosomes in marker formation

Cytogenetic studies were performed in five Hodgkin-derived permanently growing cell lines, as well as in bone marrow cells from two Hodgkin patients, one of which suffering from acute myeloid leukemia after Hodgkin's disease. No consistent and common marker chromosome was found, but certain chromosome regions seemed to be nonrandomly involved in marker formation. These are chromosome bands 7q22, 7q32, 7q36, 2q33, 1p22, 11q21/23, 14q32, 15p12, and 21q21. The importance and significance of these chromosomal findings are discussed in reference to data from the literature.

A new characteristic karyotypic anomaly in lymphoproliferative disorders

A new characteristic chromosome anomaly t(11;14)(q14;q32?) in lymphoproliferative disorders (LPD) is described in 4 cases. The extra material was found on a "14 chromosome (14q+) and belonged to the long arm of one "11 chromosome in 3 cases and to the long arm of a "14 in the other case. These cases confirm that the distal end of chromosome 14q may function as a "receptor site," according to the hypothesis of Kaiser-McCaw et al. and also tend to indicate that chromosome "14 may not be unique in showing so-called "donor" and "receptor sites," and that other chromosomes, in casu chromosome "11, may behave similarly.

Origin of the translocated segment of the 14q+ marker in non-Burkitt lymphomas

The cytogenetic findings by G-banding in two histiocytic lymphomas are described. Both tumors had a stemline with a 14q+ marker. The origin of the extra segment on No. 14 was determined, and it was different in the two cases. These observations, and those from non-Burkitt lymphomas with 14q+ markers reported in the literature, indicate an inconsistent pattern for the origin of the extra material on No. 14. The only feature in common for all cases is instability of the distal region of the long arm of No. 14, and liability of this region to be involved in structural rearrangements, particularly translocations.