The function of c-myc in physiology is only partially known. Its product has DNA binding properties and plays a role in the control of proliferation and differentiation. In general, increased c-myc expression leads to proliferation and abolishment of differentiation.
View Article and Find Full Text PDFClonality of myeloid and lymphoid cell fractions obtained from peripheral blood (PB) or bone marrow (BM) of five patients with a myelodysplastic syndrome (MDS), was studied by combined immunophenotypic analysis and DNA in situ hybridization. This novel technique enables quantitative and direct analysis of cytogenetic alterations in nondividing cells of distinct cell lineages. Four patients with a trisomy 8 and one patient with a translocation (1;7) were studied.
View Article and Find Full Text PDFIncreased numbers of TcR gamma delta + T cells are present in the small intestinal epithelium of patients with coeliac disease (CoD). Their function, however, is unknown. In order to facilitate detailed functional studies, intestinal gamma delta T cells have been isolated from small intestinal biopsies of patients with CoD (n = 18) and controls (n = 14).
View Article and Find Full Text PDFGenes Chromosomes Cancer
March 1992
Bone marrow cells of four patients with t(1;7) and myelodysplasia or acute myeloid leukemia were analyzed using nonradioactive in situ hydridisation. As probes, centromeric alphoid DNA sequences of chromosomes 1 and 7, a satellite DNA probe for 1q12, and chromosome-specific libraries of chromosomes 1 and 7 were used. The breakpoints of the t(1;7)(p11;p11) as determined by banding analysis could be studied more accurately, and the recently proposed designation t(1;7)(cen;cen) was confirmed in all four cases.
View Article and Find Full Text PDFThe pathogenesis of pulmonary leukostasis in leukemia was studied in a rat model by investigating the course of its development. Leukemia was induced by inoculating rats with leukemic cells. The earliest stage of leukostasis was found from day 14 onward, when leukemic cells appeared in the peripheral blood, and was characterized by accumulation of leukemic cells at the capillary level.
View Article and Find Full Text PDFTwenty-two diffuse aggressive B-cell lymphomas of the gastrointestinal tract were studied using light microscopic examination, immunohistochemical methods, and Southern blot analysis. The results suggest that diffuse aggressive B-cell gastrointestinal tract lymphomas may be divided into two groups: large cell lymphomas and small noncleaved cell lymphomas. Large cell lymphomas often involve the stomach; commonly express the lymphocyte adhesion molecules CD44, LFA-1 (CD11a and CD18), and CD54; and may express monotypic cytoplasmic immunoglobulin in approximately one third of cases.
View Article and Find Full Text PDFAims: To investigate the feasibility of non-radioactive in situ hybridisation (ISH) for the identification of sex-mismatched plastic embedded bone marrow biopsy specimens.
Methods: After a suspected accidental transposition of two glycol-methacrylate embedded bone marrow specimens, in situ hybridisation with sex chromosome specific probes was performed.
Results: Quantitative analysis of the hybridisation signals established unequivocably the origin of the specimens.
This case report describes a patient with localized hyaline-vascular (H-V) type Castleman's disease with concomitant malignant B-cell lymphoma. Malignant lymphoma has been described in association with multicentric type Castleman's disease, but not in association with the localized H-V type. Evidence for a relation between the two lesions in this patient by means of histologic, flow-cytometric, cytogenetic and gene rearrangement studies was not found.
View Article and Find Full Text PDFThe t(14; 18)(q32;q21) chromosomal translocation, characteristic of follicular lymphoma, couples the bcl-2 protooncogene on chromosome 18 to the immunoglobulin heavy-chain joining region (JH). This results in a deregulated transcription rate of bcl-2, suggesting a major role of the t(14;18) translocation in lymphomagenesis. By using a sensitive polymerase chain reaction technique specific for the major breakpoint region t(14;18), we now demonstrate the presence of bcl-2/JH rearrangements in lymph nodes and tonsils with follicular hyperplasia in 13 of 24 cases (54%).
View Article and Find Full Text PDFLarge cell lymphomas (LCLs) are heterogeneous in morphology, clinical presentation, and behavior. We studied 52 de novo LCLs of B-cell type for rearrangements of the bcl-2 and c-myc oncogenes by Southern blot analysis and related these data to the primary site of presentation, stage, and cytomorphology. Thirteen tumors had comigrating rearrangements of JH and bcl-2, indicative of a t(14;18).
View Article and Find Full Text PDFIn a phase II study, 12 patients with a myelodysplastic syndrome (MDS) and anaemia (nine transfusion-dependent) were treated with recombinant human erythropoietin (rHuEpo) to assess the therapeutic effect on erythropoiesis and on transfusion requirement. Patients with a low risk of developing acute leukaemia were included, i.e.
View Article and Find Full Text PDFThe value of DNA-flow cytometry and clinico-pathological prognostic factors for the prediction of local recurrences after breast-conserving therapy (BCT) were evaluated in a retrospective study. Thirty-one patients with a local recurrence were compared with 31 matched patients without a local recurrence. Morphology and DNA-indices of the local recurrences and their corresponding primary tumours were compared.
View Article and Find Full Text PDFThree cases of de novo acute B-cell lymphoblastic leukemia are presented, all with an unusual phenotype, involvement of translocation t(14;18) and additional chromosomal abnormalities, including translocation t(8;14) and deletion of chromosome 9. In contrast to normal FAB-L2 or FAB-L3 acute lymphoblastic leukemia (ALL), these leukemias did not express cytoplasmatic and membranous immunoglobulin. The combination of translocation t(14;18) and additional chromosomal events on the other chromosome 14 account for the lack of immunoglobulin expression.
View Article and Find Full Text PDFNonrandom chromosomal translocations like the t(14;18), t(8;14), and t(11;14) are found in distinct types of B-cell malignancies. Recent molecular studies concerning their structure and origin showed that many translocations occur in early precursor B cells and may be interpreted as aberrant immunoglobulin gene rearrangements. The available data from in vitro experiments, transgenic mice, and normal human individuals indicate that these translocations are essential but insufficient for full tumorigenesis.
View Article and Find Full Text PDFA retrospective clinical study was performed to determine the clinical impact of neutropenic enterocolitis (NE) in adult patients with acute leukemia and non-Hodgkin's lymphoma treated with cytosine arabinoside (Ara-C)-containing regimens. The diagnosis of NE was restricted to conditions with clinical signs of peritonitis, ileus, or intestinal hemorrhage. Forty episodes of NE were noted during 461 Ara-C-containing courses (8.
View Article and Find Full Text PDFAn unusual case of granulocytic sarcoma with a large retro-orbital tumor mass is described. The tumor had an uncommon cytomorphology and ultrastructure that mimicked a signet ring cell lymphoma. It was negative by chloroacetate esterase (CAE) stain.
View Article and Find Full Text PDFForty-four B-chronic lymphocytic leukemias (CLL) were studied by Southern blot analysis using probes for the Ig genes and bcl-1, bcl-2 (major, minor and 5' breakpoint region), bcl-3, c-myc, and retinoblastoma (Rb) loci. Eight cases had three or more rearranged JH bands, indicating oligoclonality, clonal evolution, or chromosomal translocation. One case had a rearrangement of the bcl-1 locus and three of the bcl-2 locus.
View Article and Find Full Text PDFA spontaneously growing EBV-negative B-cell line (DoHH2) was established from the pleural fluid cells of a 60-year-old man with centroblastic/centrocytic non-Hodgkin's lymphoma, that had transformed into an immunoblastic lymphoma. The pleural fluid cells and the DoHH2 cells expressed IgG lambda, were reactive with CD10 and CD19 monoclonal antibodies, and showed by cytogenetic analysis 48,XY, +7, +del(12)(q24), t(14;18)(q32;q21). Southern blot analysis of mini-satellite DNA patterns, and of rearrangements of the immunoglobulin genes and bcl-2, confirmed that the cell line was derived from the patient's clonal lymphoma cells.
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