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We have examined three cases of human lymphoma bearing a t(2;18)(p11;q21) chromosome translocation. The bcl-2 gene appeared to be rearranged in all three cases and breakpoints were clustered in the 5' flanking region of the gene. In all three cases, bcl-2 was juxtaposed to J segments of the Ig kappa gene. This juxtaposition of the bcl-2 and Ig kappa genes is very similar to the variant chromosome translocations of Burkitt lymphoma that juxtapose the c-myc locus to IgL genes.

In our series of 134 patients with a diagnosis of non-Hodgkin's lymphoma (NHL) and clonal chromosomal abnormalities, three were found to show an identical t(3;22)(q28;q11) translocation. All were old patients with isolated lymphadenomegaly and diffuse large noncleaved cell lymphoma. All expressed a B cell immunophenotype, and all entered a complete remission when treated with aggressive chemotherapy. This translocation could, therefore, delineate a particular subtype of diffuse large cell NHL.

Most human follicular lymphomas bear the specific t(14;18) translocation that juxtaposes the 3' region of bcl-2 to the IgH gene on chromosome 14q+. In some rare cases, t(2;18) and t(18;22) translocations have been observed that involve bcl-2 and either Ig kappa or lambda genes. Strikingly, in these cases all the breakpoints on chromosome 18 are located in the 5' end the bcl-2 gene. These rearrangements are very similar to those recently found in a significant proportion of CLL. Thus, bcl-2 rearrangements in malignant lymphomas cluster in at least three regions: the so-called major breakpoint region (mbr) and minor cluster region (mcr) in more than 85% of t(14;18) translocation, and the newly characterized region 5' of the gene. We propose to call this new cluster region vcr (for variant cluster region).

The monoclonal IgM kappa protein from a patient with Waldenström's macroglobulinaemia displayed antibody like activity against muscle and alpha-actinin. An Epstein-Barr virus associated lymphoid cell line, spontaneously established from blood lymphocytes, has been continuously secreting an immunoglobulin of the same isotype, isoelectric focusing spectrotype and reactivity; the cell line is probably leukaemic in origin since all cells display the translocation t (1; 19) and are aneuploid. We suggest these two monoclonal immunoglobulins have a common malignant origin.

In order to study the antitumour activity of taxol (a diterpene of the taxane type) isolated from Yew: Taxus baccata L. (Taxacae), human tumours implanted as xenografts in athymic Mice were used. Swiss nude mice were treated subcutaneously (12.5 mg/kg/injection/day for 5 consecutive days out of 7, over a period of 3 weeks). Treatment by taxol of a liver metastasis of a breast tumour, a tongue primary tumour and a skin metastasis of bronchial carcinoma gave statistically significant results (0,01 greater than P greater than 0,001 and P less than 0,001). However, taxol showed a very moderate antitumour activity against a transplanted primary tumour of the colon.

A significant decrease of sister chromatid exchange (SCE) frequencies was observed in Bloom's syndrome(BS) fibroblasts by cocultivation with normal fibroblasts at 5:1, 1:1, 1:5 ratios, and by culture in medium previously used to support normal fibroblasts. On the other hand, the SCE rate of normal fibroblasts was not modified. These results are compared with those from other studies and discussed.

One of the children of a t(15;22) (q111;p11) woman has lost the minute metacentric der(15) without any clinical consequence, indicating the inocuity of the 15pter----q111 and 22pter----p11 monosomies. The segregation mechanism of this monosomy and, from this family, the relation between reciprocal translocations and Robertsonian translocations are discussed. Another subject with r(22) in the same family questions on an hypothetic common origin.

The authors studied a series of 25 rheumatoid wrists, stages II and III according to Steinbrocker or Larsen, treated between 1981 and 1983 by realignment-stabilization synovectomy. The mean follow-up period was 2 1/2 years. The different steps of the operation--articular and tenosynovectomy, tendon transfers associated with dorsal ligamentoplasty--have an additive effect in achieving relief of pain, with preservation of the pre-existing mobility and long-term stability in both the frontal and sagittal planes. In other studies, resection of the ulnar head results in a 40 p. cent increment in instability with notably aggravation of ulnar sliding. Preservation of the distal radioulnar articulation according to Sauve-Kapandji's operation constitutes a new approach to rheumatoid arthritis and, in our opinion, appears to be simple and is very efficient in stabilizing the wrist immediately, thus allowing early rehabilitation of these patients. Long-term stability is affirmed by clinical and roentgenologic follow-up.

Cytogenetic study of a case of Bloom's syndrome (number 46 of the international registry) confirms the excess of exchanges in all cellular types with the exception of a minority of lymphocytes and of two lymphoblastoid cell lines. These exchanges are produced in an X or U fashion between sister chromatids or between homologous chromatids and produce both simple and complex figures for which symmetry is the common feature. Some of these structures are rearranged secondarily, producing centric or acentric fragments and marker chromosomes. Triradial configurations are considered to be the result of exchanges rather than of partial endoreduplication. Chromatid and chromosome breaks are interpreted to result from incomplete exchanges. It is suggested that the general propensity for exchanges is the primary event responsible directly or indirectly for the cytogenetic observations rather than a defect in one of the DNA-repair mechanisms. No increase in mitomycin C sensitivity appears in vitro. The excess of SCEs is partially correlated by contact in vitro with normal cells and to a lesser degree by the culture medium in which the cells were grown.

The human cell line U 937 spontaneously expresses monocytic maturation and can be induced into macrophage-like cells when treated with retinoic acid, sodium butyrate, or 2,3-O-tetra decanoylphorbol-13-acetate. We have selected a subclone, designated UM 384, that expresses granulocytic characteristics and can be induced to mature to granulocytes after exposure to retinoic acid, actinomycin D, and dimethylsulfoxide, and to monocyte-like cells when treated with sodium butyrate and phytohemagglutinin-stimulated leukocyte-conditioned medium. These cells retain the same constitutive markers as the parent line including histocompatibility leukocyte antigens and karyotype but share numerous chromosomal abnormalities, mainly t(X;8) (p21;q12).

A cell line (LAMA-84) has been established from the blood of a patient with chronic myeloid leukemia in acute phase. LAMA-84 cells retained the patient's chromosome abnormalities, i.e., triplication of all chromosomes except chromosome 18, the presence of Philadelphia (Ph) chromosome in 4-5 copies, and the presence of chromosome markers. LAMA-84 cells have morphological features of undifferentiated blast cells, but analyses have indicated that they belong to the megakaryocytic lineage; platelet peroxidase (PPO) was found in 8.5% of cells; LAMA-84 cells reacted spontaneously with poly- and monoclonal antibodies against the platelet glycoproteins (GP) IIb, IIIa, and the GPIIb/IIIa complex, whose presence was confirmed by crossed immunoelectrophoresis. LAMA-84 cells lack the membrane characteristics of lymphoid and mature granulocytic cells but do, however, react with certain antibodies to immature myeloid cells. Furthermore, they are positive with an antiglycophorin antibody, and contain alpha- and gamma-globin mRNA, thus demonstrating erythroid marker expression. Thus LAMA-84 is a tripotent, megakaryocytic, erythroid, and granulocytic cell line. The megakaryocytic and erythroid markers were enhanced by the addition of DMSO, butyrate, TPA, and hemin. The LAMA-84 cell line represents an interesting tool for the study of megakaryocytic and erythroid differentiation and the mechanisms of neoplastic growth.