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Query: UMLS:C0026986 (myelodysplastic syndrome)
 14,926 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Clonal analysis of lymphocytes from patients with myelodysplastic syndrome (MDS) has been carried out using X-chromosome inactivation patterns detected by the probe M27 beta, and by polymerase chain reaction amplification of the immunoglobulin heavy chain gene hypervariable region, CDR3. Of 32 female patients heterozygous for M27 beta only seven (22%) demonstrate monoclonality of peripheral blood lymphocytes. 12 (37%) give unequivocal polyclonal results and the remaining cases give patterns of X-inactivation which cannot be interpreted either way. A study of 68 MDS patients showed five (7%) with a population of B-cells with a monoclonal rearrangement of CDR3 compared with none out of 60 normal individuals, none out of 15 with B-non Hodgkin lymphoma (B-NHL) in remission and 19 out of 25 (75%) of cases of B-chronic lymphocytic leukaemia (B-CLL). Monoclonal lymphocytes were found by both techniques in only two females with MDS. We conclude that the presence of polyclonal lymphocytes is a common finding in patients with MDS.
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PMID:Clonal lymphocytes are detectable in only some cases of MDS. 139 Feb 7

The arrangement of the immunoglobulin and T-cell receptor genes has been analysed in 72 cases of primary myelodysplastic syndrome and 17 cases of acute nonlymphocytic leukemia. DNA was extracted from bone marrow aspirates, digested with at least two restriction enzymes, and hybridised with probes for the joining region of the immunoglobulin heavy chain gene, the constant region of the T-cell receptor beta chain gene, and the joining region of the T-cell receptor gamma chain gene. All cases showed germline arrangements of the immunoglobulin and the T cell receptor genes. Thus, true interlineage infidelity, myeloid to lymphoid, is a rare occurrence in myelodysplasia and in myeloid leukemias.
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PMID:Absence of immunoglobulin and T-cell receptor gene rearrangements in myelodysplastic syndromes and acute nonlymphocytic leukemias. 329 39

The clinical and biological characteristics of myelodysplastic syndrome (MDS) in acute leukemic transformation were studied in 23 patients. All had myeloid transformation according to FAB criteria, but coexpression of lymphoid-associated antigens was detected in five of the 20 patients who underwent an immunophenotypic study. Rearrangement of the immunoglobulin heavy chain gene was also observed in one of the five patients who coexpressed lymphoid markers and that of the T-cell receptor beta chain gene in another one. None had pure lymphoid transformation. Clonal chromosomal abnormalities were noted in 12 (63%) of the 19 patients who underwent cytogenetic study, most commonly - 7 (six patients or 32%). In the 18 patients who underwent serial analyses both at MDS diagnosis and at acute transformation, seven (39%) underwent karyotypic evolution. The most common new or additional aberrations were +8 and +21. N-ras gene mutation was detected in two of the nine patients at acute leukemic transformation. The median interval from diagnosis of MDS to onset of acute transformation was 10 months (1-36 months). Patients with a normal karyotype at diagnosis had a significantly longer chronic phase duration than those with chromosomal abnormalities (median of 20 months vs. 5 months). However, all had a short survival time after diagnosis of acute leukemia, whether chromosomal anomalies were present or not.
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PMID:Acute leukemic transformation of myelodysplastic syndrome--immunophenotypic, genotypic, and cytogenetic studies. 756 69

Aplastic anaemia (AA) can be associated with disorders that are known to exhibit clonal haematopoiesis, like paroxysmal nocturnal haemoglobinuria (PNH), myelodysplastic syndrome (MDS) and acute myeloid leukaemia (AML). It appears that the long term survivors of severe AA treated with immunosuppressive agents such as ATG have a continuing, late mortality caused by the evolution of clonal disorders which are not usually seen when bone marrow transplant is used. In children, typical AA may precede the onset of acute lymphoblastic leukemia (ALL). The aplastic phase is often transient and remission may be spontaneous or rapidly induced by steroid, and followed a few months later by acute leukaemia. This modality of presentation may be observed in up to 2-3% of all cases of paediatric ALL. A 13-year old girl who presented with two spontaneously reversible episodes of marrow aplasia has been reported recently. She developed ALL 8 months later. Southern analysis showed identical clonal immunoglobulin heavy chain gene rearrangement bands in her leukaemic cells as well as the marrow cells obtained at the two aplastic episodes. Hypoxanthine phosphoribosyltransferase polymorphism studies showed that all the ALL blast cells, bone marrow and peripheral cells during the two aplastic episodes all exhibited clonal haematopoiesis with the same X-chromosome inactivated. This case provides strong evidence that AA and ALL can represent evolution of the same abnormal clone.
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PMID:Childhood acute lymphoblastic leukaemia and aplastic anaemia. 806 86

Clonality, in MDS, can only be assessed in patients with chromosomal rearrangements or in females heterozygote for X chromosome restricted polymorphisms. "Illegitimate" rearrangements of the immunoglobulin heavy chain (IgH) gene and incomplete rearrangements involving V delta 2 and D delta 3 segments of the T-cell receptor delta (TcR delta) gene are seen in some cases of AML, and AML post-SMD, and can be detected by a sensitive PCR method. In order to analyse clonality in additional cases in MDS, we looked for Ig H and TcR delta gene rearrangement by PCR in 95 cases of MDS. A rearrangement of the Ig H gene was seen in 2 of the 95 patients: in the circulating blood of 2 of the 36 cases of chronic myelomonocytic leukaemia (CMML) and in none of the marrow samples of the other 59 MDS. A rearrangement of the TcR delta gene (involving V delta 2 and D delta 3 segments) was seen in three cases (in the circulating blood of two other CMLL patients, and in the bone marrow of another MDS patient). Twenty-five of the 90 cases of MDS with negative PCR findings, in addition to the five cases with positive PCR findings underwent Southern blot analysis of Ig H and TcR delta genes, and PCR analysis of V delta 1 and J delta 1 segments of the TcR delta gene. Those examinations were normal in all the cases tested. In patients with positive PCR findings for Ig H or V delta 2 D delta 3 rearrangements, the proportion of rearranged cells was evaluated at 1-5% in four cases, and 5-10% in the remaining patient. Because the analysis was performed on total circulating leukocytes or total nucleated marrow cells, the nature of the clonal population in positive cases (lymphoid cells? myeloid cells? blasts?) could not be determined. From a practical point of view, Ig H and TcR delta gene rearrangements seem to very rare in MDS, and cannot be used as clonality markers in most cases.
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PMID:Immunoglobulin and T-cell receptor delta gene rearrangements are rarely found in myelodysplastic syndromes in chronic phase. 818 27

Because human lymphotoxin (LT) was originally isolated from a lymphoblastoid cell line, we investigated the role of this molecule in three newly established Epstein-Barr virus (EBV)-infected human B cell lines. These lines were derived from acute lymphoblastic leukemia (Z-6), myelodysplastic syndrome (Z-43), and acute myelogenous leukemia (Z-55) patients who had a prior EBV infection. Each lymphoblastoid cell line had a karyotype that was different from that of the original parent leukemic cells, and all expressed B cell, but not T cell or myeloid surface markers. In all three lines, rearranged immunoglobulin heavy chain joining region (JH) bands were found, and the presence of EBV DNA was confirmed by Southern blotting. Z-6, Z-43, and Z-55 cell lines constitutively produced 192, 48, and 78 U/ml LT, respectively, as assessed by a cytotoxicity assay and antibody neutralization. Levels of tumor necrosis factor (TNF) were undetectable. Scatchard analysis revealed that all the cell lines expressed high-affinity TNF/LT receptors with receptor densities of 4197, 1258, and 1209 sites/cell on Z-6, Z-43, and Z-55, respectively. Furthermore, labeled TNF binding could be reversed by both unlabeled TNF, as well as by LT. Studies with p60 and p80 receptor-specific antibodies revealed that the three lines expressed primarily the p80 form of the TNF receptor. When studied in a clonogenic assay, exogenous LT stimulated proliferation of all three cell lines in a dose-dependent fashion at concentrations ranging from 25 to 500 U/ml. Similar results were obtained with [3H]TdR incorporation. Monoclonal anti-LT neutralizing antibodies at concentrations of 25-500 U/ml inhibited cellular multiplication in a dose-dependent manner. It is interesting that in spite of a common receptor, TNF (1,000 U/ml) had no direct effect on Z-55 cell growth, whereas it partially reversed the stimulatory effect of exogenous LT. In addition, TNF inhibited Z-6 and Z-43 cell proliferation, and its suppressive effect was reversed by exogenous LT. Both p80 and p60 forms of soluble TNF receptors suppressed the lymphoblastoid cell line proliferation and their inhibitory effect was partially reversed by LT. Our data suggest that (a) LT is an autocrine growth factor for EBV-transformed lymphoblastoid B cell lines; and (b) anti-LT antibodies, soluble TNF/LT receptors, and TNF itself can suppress the growth of lymphoblastoid cells, probably by modulating or competing with LT.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Lymphotoxin is an autocrine growth factor for Epstein-Barr virus-infected B cell lines. 838 56

We report two cases of marginal zone B-cell lymphoma in two patients 6 and 18 years of age, respectively (cases 1 and 2) who had no clinical evidence of immunodeficiency or risk factors for human immunodeficiency virus (HIV) infection. Histologic analysis in both cases revealed diffuse nodal effacement by a monotonous population of atypical lymphoid cells with abundant pale cytoplasm and round to oval nuclei, with very infrequent mitotic activity. The neoplastic cells in both cases were of B-cell lineage (CD20 and CD79a positive), with CD43 coexpression. One case showed monoclonal light chain expression, and polymerase chain reaction analysis demonstrated clonal rearrangements of the immunoglobulin heavy chain gene in both cases. Abnormal cytogenetic findings were detected in case 2, in which metaphase spreads revealed trisomy 13 (karyotype 47, XY, +13). Although trisomy 13 has been described in association with acute nonlymphocytic leukemias and myelodysplastic syndromes, this case represents the first documented association of trisomy 13 with marginal zone B-cell lymphoma. Interphase cytogenetics analysis for trisomy 3, reported to be associated with mucosa-associated lymphoid tissue (MALT) lymphomas, was negative in both cases. Although low-grade lymphomas of the MALT type have been reported in HIV-positive patients, the two cases reported here are unique in that they occurred in young patients without HIV infection or any other evidence of immunodeficiency.
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PMID:Marginal zone B-cell lymphoma with monocytoid B-cell lymphocytes in pediatric patients without immunodeficiency. A report of two cases. 898 Mar 74

The development of myelodysplastic syndrome (MDS) and/or acute myeloid leukemia (AML) has rarely been observed in patients with chronic B-lymphocytic leukemia (B-CLL). So far, the discussion concerning the pathogenesis of the simultaneous occurrence of these two malignancies has been speculative, opposing the theory of two separate malignant clones to the theory of a common stem cell malignancy. We describe the case of a 77-year-old woman who developed MDS after 8 years of an indolent course of B-CLL. The diagnosis of MDS was based on bone marrow (BM) morphology, showing the typical picture of a refractory anemia with excess of blasts (RAEB). The clinical course of MDS was aggressive, terminating in AML within only 6 months. Immunophenotyping of BM and peripheral blood (PB) cells revealed a CD34+/ CD13+/CD33-/CD19-blast cell population and a CD19+/CD5+ B-cell population with kappa light chain restriction. Molecular analysis of PB and BM demonstrated the presence of an immunoglobulin heavy chain (IgH) gene rearrangement by polymerase chain reaction (PCR) amplification of genomic DNA with three different pairs of consensus primers. Cell-sorting experiments showed that the IgH gene rearrangement was present only in the CD19+/CD34- B-cell population, but not in the CD34+/CD19- blast cells. Furthermore, X-chromosome inactivation pattern analysis revealed two differently methylated cell populations. These experiments demonstrate the concomitant existence of two different clones in a patient with CLL-MDS/AML.
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PMID:Myelodysplastic syndrome/acute myeloid leukemia supervening previously untreated chronic B-lymphocytic leukemia: demonstration of the concomitant presence of two different malignant clones by immunologic and molecular analysis. 917 49

Case history of a seventy year old man with myelodysplastic syndrome is presented. The disease terminated into acute leukaemia in 22 months. The pure, B lymphoid stem cell nature of the leukaemic cells has been proved, beside morphology and cytochemistry, by detailed flow cytometric phenotyping and PCR amplification as well as sequencing of the immunoglobulin heavy chain gene CDR3 region.
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PMID:[A case of myelodysplastic syndrome transforming into acute B-cell lymphoid leukemia]. 926 46

The case history of a 70-year-old man with myelodysplastic syndrome terminated into acute leukemia in 22 months is presented. The leukemic cells exhibited multifocal acid phosphatase positivity and expressed TdT, CD45, CD34 and HLA-DR but not myeloid, monocytic or megakaryocytic differentiation antigenes. The genotypic analysis revealed clonal immunoglobulin heavy chain gene rearrangement. These phenotypic and genotypic analyses of the blastic cell population suggest that myelodysplastic syndrome may transform to pure acute lymphoblastic leukemia of B-cell origin.
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PMID:Phenotypic and genotypic analyses of blastic cell population suggest that pure B-lymphoblastic leukemia may arise from myelodysplastic syndrome. 958 74


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