Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We cloned the t(10;14) recurrent translocation from CD3-negative T-cell acute lymphoblastic leukemia cells. The breakpoint at 14q11 involved an intermediate rearrangement of the delta T-cell receptor locus, suggesting that the translocation arose at the time of antigen receptor assemblage. Translocation introduced chromosome segment 10q24 as proven by hybridization of a breakpoint-derived probe to flow-sorted chromosomes and metaphase chromosomes. Two t(10;14) breakpoints were clustered within a 600-base-pair region of 10q24 but no heptamer-spacer-nonamer motifs resembling T-cell receptor/immunoglobulin rearrangement signals were noted at the breakpoint. A locus distinct from terminal deoxynucleotidyltransferase was found at 10q24. Evolutionarily conserved regions surrounding the 10q24 breakpoint were examined for transcriptional activity. A region telomeric to the 10q24 breakpoint, expected to translocate to the der(14) chromosome, recognized an abundant 2.9-kilobase RNA in a t(10;14) T-cell leukemia. This locus was not active in a variety of other normal and neoplastic T cells, arguing that it was deregulated by the introduction of the T-cell receptor. This locus is a candidate for a putative protooncogene, TCL3, involved in T-cell neoplasia.
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PMID:The t(10;14)(q24;q11) of T-cell acute lymphoblastic leukemia juxtaposes the delta T-cell receptor with TCL3, a conserved and activated locus at 10q24. 232 74

We describe the clinical, ultrastructural, and immunophenotypical characteristics of four cases of an unusual type of T cell leukemia. Clinical features included high WBC, ranging from 26-148 x 10(9)/liter, bone marrow infiltration, splenomegaly, and lymphadenopathy. Skin involvement was not documented at presentation, but it was seen as a terminal event in one patient with a pattern of dermal lymphocytic infiltration different from that usually seen in Sezary syndrome. By ultrastructural analysis, the circulating lymphoid cells were indistinguishable from small Sezary cells in two cases, resembled large Sezary cells in one case, and consisted of a mixture of small Sezary cells and prolymphocytes in the remaining case. The cells from all cases had a mature T cell phenotype, TdT-, CD1a-, CD2+/-, CD3+, CD5+. In addition, the cells were either CD8+, CD4- or CD8+, CD4+ or CD4-, CD8-; and, in only one case, the findings were similar to those of Sezary syndrome cells: CD4+, CD8-, CD7-, BE-2+. In the latter case, serological and immunological assays were positive for HTLV-I while these were negative in two other patients investigated. The features of these patients suggest that Sezary cell leukemia is a distinct clinico-pathological entity although the alternative diagnosis of adult T cell leukemia/lymphoma could not be excluded in the HTLV-I+ case. Sezary cell leukemia appears to be resistant to current chemotherapy regimens and is associated with an aggressive clinical course and short survival.
Leukemia 1990 Apr
PMID:Sezary cell-like leukemia: a distinct type of mature T cell malignancy. 236 82

Hematological and cytogenetic characteristics of 75 cases of therapy-related acute non lymphoid leukemia (t-ANLL) occurring in Hodgkin's disease (HD) are analysed in this multi-institution study. Combined radio and chemotherapy had been given in 88 per cent of patients, either as adjuvant (44 per cent) or as salvage modality (44 per cent). Radiotherapy alone and chemotherapy alone had been given in 3 per cent and 9 per cent respectively. Eighty per cent of patients were in remission of HD and 71 per cent off-therapy while developing leukemia. The median latent time from remission of HD to leukemia was 34 months. The myeloblastic variety of leukemia accounted for 43 per cent of total cases; the myelomonocytic and monocytic for 17 per cent and 4 per cent, the promyelocytic and erythroblastic variants for 5 per cent and 7 per cent of t-ANLL. Twenty four per cent of cases were unclassifiable; one of these was TdT-positive. Dysplastic features of erythrocytic line were invariably present with circulating erythroblasts; defects of granulocytes, circulating megathrombocytes and micromegakaryocytes were also present. Bone marrow hypoplasia and marked fibrosis were documented in 47 per cent and 30 per cent of cases. Preleukemia heralded overt leukemia in 73 per cent of cases; 37 per cent had refractory anemia with no excess of blasts; 16 per cent of preleukemias were unclassifiable. Cytogenetics revealed chromosome abnormalities in 83 per cent of cases; 72 per cent presented chromosome 5 and/or 7 monosomy or partial deletion (5q- or 7q-) of the long arm (94 per cent in the combined modality therapy group). In 3 cases, a pure monosomy 7 was observed; in none 5q-alone. Response rate to conventional therapy was 14 per cent; low and high-dose cytarabine were of little benefit. Long-term CR (28 + and 16 + months) was achieved in 2 cases with allogeneic bone marrow transplantation (BMT) as first-line therapy. A better knowledge of t-ANLL in HD and new therapies, including BMT, may improve the prognosis of this late complication of intensive HD treatment.
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PMID:Treatment-related leukemia in Hodgkin's disease: a multi-institution study on 75 cases. 243 31

Lymphocyte subpopulations in human cord blood have been examined using monoclonal antibodies, visualized with immunogold. The proportions of T11, T4, T8, and B1 cells in cord blood are very similar to values in adult peripheral blood. Some evidence of lymphocyte immaturity in cord blood is suggested by the presence of 12% CALLA-positive cells and the sum of T4 and T8 cells significantly exceeding the number of T11 cells; however, there were no TdT-positive cells. The presence of CALLA-positive lymphocytes in normal cord blood should be borne in mind when investigating blood smears from neonates for congenital leukemia.
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PMID:Characterization of lymphocyte subpopulations in human cord blood using the immunogold staining technique. 244 85

DNA ligases are involved in DNA replication, repair and recombination. Consecutively to partial purification, these enzymes have been studied in acute leukemias and subclasses. There is a good correlation between this enzyme activity and the percentage of cells in S phase in acute myeloblastic leukemia. However, in acute lymphoblastic leukemia, a low and even absent activity (T-ALL) is observed. It is shown that in this type of leukemia, the absence of activity is due to either the absence or the non expression of the DNA ligase gene. The results are discussed in terms of the correlation between the absence of ligase activity and the expression of the TdT phenotype.
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PMID:[Enzymes involved in the metabolism, replication and repair of DNA in acute leukemias (DNA ligases)]. 244 48

Current views about the origin of acute lymphoid leukemia (ALL) emphasize the importance of maturation arrest at a precursor cell level. Recently, the CD22 antigen has been identified in the cytoplasm of normal bone marrow-borne immature B lineage cells, while the CD3 antigen (epsilon chain) has been detected within normal immature thymic blasts. In the first part our study performed on 100 cases of known acute leukemias, the expression of such cytoplasmic molecules, referred to as cCD22 and cCD3, was analyzed together with their appearance in the leukemic cells' membrane (mCD22 and mCD3). The presence of cCD22 in B-lineage ALL and that of cCD3 in T-ALL has indeed fully confirmed the diagnosis reached by other markers, and mCD22 and mCD3 were expressed on only a few cases of B- and T-lineage ALL, also revealing a degree of developmental asynchrony within leukemic blasts. In the subsequent analysis both cCD22 and cCD3 have been included in a standard panel of diagnostic reagents applied on 500 consecutive cases of acute leukemia. Here the aim was to analyze both the diagnostic precision of individual markers and the heterogeneity of various leukemic types in terms of the expression of membrane and intracellular antigens and their cytochemical features (Sudan Black B and esterases). It has been found that cCD22 and cCD3 are exquisitely specific for B-precursor ALL (TdT+, CD19+) and T-ALL (TdT+, CD7+), respectively, while both markers are absent in acute myeloblastic leukemia (AML) and acute myelomonocytic and monocytic leukemia (AMML/AMoL). These observations contrast the findings which demonstrate that 31% of cases among nonlymphoid acute leukemia (including AML and AMML) express CD7 and/or TdT. The study of myeloid antigens detected by CD13, CD33, and CD14 is also informative and complementary, both in diagnosing and subdividing the AML and AMML/AMoL groups. The peculiar main observation of this study is that only with the combined use of these markers in a microplate assay for membrane antigens, followed by double staining for intracellular antigens such as terminal deoxynucleotidyl transferase, cCD3, cCD22, c mu heavy chain, and T cell receptor beta, it is possible to safely establish the lineage affiliation and subgrouping of virtually all acute leukemias. Among these cases are those with aberrant combinations of markers, including 14% of B-lineage ALL (cCD22+,CD19+,TdT+) and a single case T-ALL (cCD3+,CD7+,TdT+), which exhibit CD13 and/or CD33 antigens, cases with mixtures of ALL and AML blasts, and 1.2% of acute leukemias which lack lineage affiliation and can be regarded as acute undifferentiated leukemia.
Leukemia 1989 Mar
PMID:The reliability of cytoplasmic CD3 and CD22 antigen expression in the immunodiagnosis of acute leukemia: a study of 500 cases. 246 63

Monoclonal antibody Leu-9 (CD 7) has been reported to be a sensitive and specific marker for T-cell lineage in leukemic processes, since it is positive in patients whose leukemic cells fail to express other T-cell antigens. To test whether Leu-9 is indeed specific for T-cell leukemias, we examined in detail 10 cases of acute leukemia in which reactions were positive for Leu-9 and negative for other T-cell-associated markers including T-11, Leu-1, T-3, and E-rosettes. Morphologically and cytochemically, 2 of these 10 leukemias were classified as lymphoblastic, 4 as myeloblastic, 2 as monoblastic, 1 as megakaryoblastic, and 1 as undifferentiated. The case of acute megakaryoblastic leukemia is the first reported case to be Leu-9 positive. None of the 10 were TdT positive. Of six cases (two monoblastic, one lymphoblastic, one myeloblastic, one megakaryoblastic, and one undifferentiated) in which we evaluated for DNA gene rearrangements, only one, a peroxidase-positive leukemia, showed a novel band on study of the T-cell-receptor beta-chain gene. We therefore conclude that Leu-9 is not a specific marker to T-cell lineage and that, in the absence of other supporting data, Leu-9 positivity should not be used as the sole basis of classifying an acute leukemia as being T-cell derived.
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PMID:Leu-9 (CD 7) positivity in acute leukemias: a marker of T-cell lineage? 247 73

Seventeen patients with acute myeloid leukaemia (AML) whose blasts co-expressed the T-cell associated CD7 antibody were identified among 160 consecutive AML cases. Fourteen had FAB defined AML according to morphocytochemical criteria, whereas three patients were classified as 'MO' on the basis of immunophenotype. The incidence of CD7 positively was particularly significant in the less differentiated subtypes M0 and M1 compared with other FAB groups (P less than 0.001). In all cases the myeloid determinants CD13 and/or CD33 were associated with CD7 expression. Other B-lymphoid (CD10, CD19) or T-lymphoid (CD2, surface and cytoplasmic CD3) markers were analysed and found to be negative. Five out of 15 cases examined were TdT+. Clonal rearrangements of the immunoglobulin heavy chain (IgH) and/or T-cell receptor (TcR) beta chain genes were identified in only three out of 13 cases. Among these, one out of five co-expressing TdT showed IgH rearrangement when analysed at the DNA level. Clinical features at presentation and response to induction therapy did not allow us to consider CD7+ AML patients as a distinct subgroup with prognostic significance. Our data indicate that CD7 expression is a common finding in immature AML, being generally found in the absence of other T-cell features. Rather than suggesting the occurrence of 'mixed leukaemia', such cases confirm a broader spectrum of CD7 reactivity and its possible identification of a particular subset of myeloid progenitors.
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PMID:CD7 positive acute myeloid leukaemia: a subtype associated with cell immaturity. 248 63

Configuration of the T cell receptor (TCR) beta, gamma, and delta chain genes, as well as immunoglobulin (Ig) heavy and light chain genes, was studied in 29 cases of E rosette-negative (pre-T cell) acute lymphoblastic leukemias that lack early B cell (CD19), myeloid (CD33), as well as most T cell associated membrane antigens such as CD1, C4, and CD8, but express CD7, cytoplasmic CD3 (cCD3), and TdT strongly, as well as CD5 and/or CD2 heterogeneously. Hematopoietic progenitor cell markers, namely HLA-DR, J5 (CD10), and My10 (CD34), further characterized this immature T ALL of putative prothymocytic phenotype. Eleven ALLs showed a germline configuration of TCR as well as Ig genes. In three cases, only TCR delta sequences were rearranged, and four additional cases were characterized by recombination of both, TCR gamma as well as TCR delta sequences. Eleven patients showed concurrent rearrangements of TCR beta, gamma, and delta chain genes. An Ig heavy chain rearrangement was observed in one case. These data support the hypothesis that, analogous to pre-B development, a cascade of TCR rearrangements occurs in pre-T cells. Moreover, findings reported here suggest that CD7, as well as CD2 and CD5, antigens appear on precursor cells prior to entry into the thymus and support a model for the developmental hierarchy of TCR genes during early T cell ontogeny.
Leukemia 1989 Jun
PMID:Rearrangement of T cell receptor beta, gamma, and delta gene loci in human pre-T cell acute lymphoblastic leukemia. 254 99

The T-cell receptor (TCR) alpha/delta chain locus on chromosome 14q11 is nonrandomly involved in translocations and inversions in human T-cell neoplasms. We have analyzed three acute T-lymphoblastic leukemia samples carrying a t(10;14)(q24;q11) chromosome translocation by means of somatic cell hybrids and molecular cloning. In all cases studied the translocation splits the TCR delta chain locus. Somatic cell hybrids containing the human 10q+ chromosome resulting from the translocation retain the human terminal deoxynucleotidyltransferase gene mapped at 10q23-q24 and the diversity and joining, D delta 2-J delta 1, regions of the TCR delta chain, but not the V alpha region (variable region of the TCR alpha chain), demonstrating that the split occurred within the V alpha-D delta 2 region. Molecular cloning of the breakpoint junctions revealed that the TCR delta chain sequences involved are made from the D delta 2 segment. The chromosome breakpoints are clustered within a region of approximately 263 base pairs of chromosome 10. The results suggest that the translocation of the TCR delta chain locus to a locus on 10q, which we have designated TCL3, results in deregulation of this putative oncogene, leading to acute T-cell leukemia.
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PMID:Clustering of breakpoints on chromosome 10 in acute T-cell leukemias with the t(10;14) chromosome translocation. 254 65


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