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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have performed gene rearrangement studies on the leukemic blasts of a patient with acute pre-B-cell leukemia. The patient had a 5 year history of follicular lymphoma, which developed into acute pre-B-cell leukemia. The leukemic blasts revealed a karyotype with two translocations, t(8; 14) and t(14; 18), characteristic for Burkitt's lymphoma and follicular lymphoma. The cells are TdT positive, do not possess surface immunoglobulin, and they show immunoglobulin gene rearrangement. The mu heavy chain and kappa light chain constant (C mu and C kappa) loci are deleted, while the gamma and lambda light chain constant (C gamma and C lambda) region genes are rearranged. Both alleles of the heavy chain joining segment (JH) are rearranged on chromosome 14q+, one of them with the bcl-2 oncogene from chromosome 18. The breakpoint of the t(14; 18) translocation occurs in the major breakpoint cluster region in the 3' untranslated region of bcl-2. On chromosome 8 a c-myc rearrangement was mapped immediately 5' to the c-myc first exon in a region involved in sporadic Burkitt lymphoma. The data are consistent with our previous hypothesis on the evolution of B-cell malignancies: a rare pre-B cell develops a t(14; 18) translocation during immunoglobulin VDJ joining that results in an expansion of a follicular lymphoma clone carrying an activated bcl-2 gene. Within the clone of pre-B cells a second translocation, t(8; 14), occurs during heavy chain isotype switching that results in the deregulation of the c-myc involved in the translocation.
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PMID:Pre-B-cell leukemia with a t(8; 14) and a t(14; 18) translocation is preceded by follicular lymphoma. 313 17

Rearrangement of the beta and gamma chain genes of the TCR gene complex and of the Ig heavy chain genes were examined in three cases of childhood acute mixed lineage leukaemia. Blast cells, classified morphologically as acute lymphoblastic leukaemia (ALL) in one child and acute non-lymphocytic leukaemia (ANLL) in the other two, all co-expressed markers associated with both T (CD7, TdT) and myeloid (CD33) cells. Cytogenetic analysis detected abnormalities associated with myeloid leukaemia. Immunoglobulin heavy chain genes were not rearranged in two patients but a novel rearrangement was seen in the third. No rearrangement of the beta or gamma chains of the T-cell receptor complex were seen. Acute mixed lineage leukaemia may thus arise from a pluripotent precursor cell capable of both lymphoid and myeloid differentiation.
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PMID:Rearrangement of T-cell receptor and immunoglobulin heavy chain genes in childhood acute mixed lineage leukaemia. 314 5

Between January, 1982 and April, 1983, 92 adult patients with acute leukaemia were investigated in our department. According to classical criteria (cytology and optical cytochemistry), 34 were classified as "non-myeloid". These were further tested with a panel of monoclonal antibodies against cell membrane, including ALB1-2 (anti-CALLA), ALB6 (anti-p24), ALB7-8-9 (BA1), OKT and HLA DR; they were also tested for E rosettes, Slg and terminal transferase (TDT). When all these markers but HLA DR were negative, patients were investigated for ultrastructural peroxidases which were found to be present in 2 cases. Among all non-myeloid leukaemias, 18 (56%) were CALLA-positive and TDT-positive acute lymphoblastic leukaemias (ALL), 2 (6%) were ALL T, 7 (22%) were CALLA-negative and TDT-positive ALL and 5 (16%) were acute leukaemias null for our markers, a phenomenon the significance of which is discussed. Patients with the CALLA-negative TDT-positive phenotype were peculiar with regard to age (mean: 50 years), female predominance, L2 cytological pattern according to the FAB classification, good prognosis (complete remission in 100% of the cases) and median survival (p less than 0,03).
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PMID:[Acute nonmyeloid leukemia in adults. Study of membrane antigens and terminal transferase. Diagnostic and prognostic value]. 315 36

An infant case of acute leukemia (AL) showed lineage infidelity and a chromosome rearrangement involving 11q23. This case was morphologically diagnosed as ALL-L2 according to the FAB classification. However, the blast cells were highly positive for monoclonal antimyeloid antigens (Mol and TG-8) and lymphoid markers (B1, J5 and TdT). These immunologic findings indicated that the blast cells had characteristics of lymphoid B-cell and myeloid lines. In the literature, so-called "11q23 chromosome abnormalities," commonly observed in acute nonlymphoblastic leukemia (ANLL) and in a subtype of acute lymphoblastic leukemia (ALL) with t(4;11) were observed in both lymphoid and myeloid acute leukemias, with some of them recently reported to have lineage infidelity. These unique characteristics may indicate the possibility that the latter is a variation of the former, and support the hypothesis that the chromosomal rearrangement at 11q23 occurs at a multipotent stem-cell level.
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PMID:Infantile acute leukemia with 11q23 chromosome abnormality and lineage infidelity. 316

One hundred ninety-two patients with previously untreated AML had TdT studies performed on their presenting BM aspirate specimens. Thirty-seven patients (19%) had greater than 5% TdT-positive (TdT+) blasts in their BM, as determined by an indirect immunofluorescence technique. CR rates were similar in both groups of patients (20/37 vs. 97/155, p = not significant) as were remission durations and median survivals. In the subset of patients younger than 60 years, patients with TdT+ blasts had an increased median survival (110 vs. 54 weeks, p = 0.1) compared with those having TdT- blasts. Six of 37 patients with TdT+ findings had t(8;21) translocations compared to 5 of 155 with TdT- findings (16% vs. 3%, p less than 0.01). Patients with more than 50% BM blast cells showing TdT positivity at diagnosis tended to be younger than those with TdT- (mean age 30.5 years and 50.3 years, p = 0.04). The presence of TdT+ blast cells in the initial marrow in patients with AML may be associated with specific cytogenetic abnormalities and may identify subsets of patients who have improved prognoses.
Leukemia 1988 Oct
PMID:Cytogenetic association and prognostic significance of bone marrow blast cell terminal transferase in patients with acute myeloblastic leukemia. 317 42

Development of monoclonal antibodies to lymphoid cells has allowed for simple methods for the classification of leukemias. Using the monoclonal antibodies, B1, B4, T1, T11, Ia, CALLA, My7, My9, and a polyclonal TdT reagent, we report a number of unusual phenotypes analyzed by flow cytometry. Two cases of mixed linkage leukemia are reported, one marked with anti-CALLA and My9, the other marked with T11 and Ia. Three rare cases of pediatric CLL are reported. Both were of B cell origin with chromosome transformation. These studies demonstrate the clinical importance of monoclonal antibodies in leukemia classification. The results also show that the so-called rare leukemias may not be as rare as previously thought.
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PMID:The utilization of monoclonal antibodies in the diagnosis of unusual leukemias. 318 Jan 37

We have analyzed the molecular genetics of the breakpoints involved in the t(8;14) and t(14;18) translocations of an acute pre-B-cell leukemia from a patient with a history of follicular lymphoma. In this patient's leukemic cells, the breakpoint of the t(14;18) translocation occurred in the major breakpoint-cluster region of the BCL2 gene and became linked to the JH4 joining-region gene segment of the immunoglobulin heavy-chain locus on the 14q+ chromosome as previously observed in follicular lymphoma. An N region and heptamer and nonamer signal sequences indicated that this translocation occurred as a mistake in VH-DH-JH joining (where VH and DH are the variable and diversity segments). In the t(8;14) translocation, the breakpoint was located immediately 5' of the first exon of the MYC protooncogene, which was juxtaposed with the C gamma 2 constant gene segment of the second 14q+ chromosome. The finding of repeated sequences typical of switch regions suggested that this translocation occurred during heavy-chain isotype switching, resulting in progression to pre-B-cell leukemia with both the t(8;14) and the t(14;18) translocations. The terminal deoxynucleotidyltransferase-positive phenotype of the patient's leukemic cells further suggests that the pre-B-cell leukemia was derived from a pre-B cell carrying a t(14;18) translocation in the original follicular lymphoma. The polymerase chain reaction method was then used to identify cancer cells in the bone marrow of the patient.
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PMID:Evolution of B-cell malignancy: pre-B-cell leukemia resulting from MYC activation in a B-cell neoplasm with a rearranged BCL2 gene. 318 43

Analysis at the DNA and RNA level revealed a mature genetic marker profile in a case of T type blast crisis of chronic myelocytic leukemia. T cell receptor beta chain gene rearrangement as well as T cell receptor alpha mRNA transcription was demonstrated in blasts of the malignant clone. Corresponding findings were obtained from immunological phenotyping. Blasts were found to be CD7+, CD1+, CD3+, CD4+, CD8+, and TdT- and classified as common/mature thymocytes. The presence of the breakpoint cluster region gene on chromosome 22 excluded the possibility of a second neoplastic process.
Leukemia 1988 Mar
PMID:T cell receptor alpha mRNA transcription in T-lymphoblastic transformation of chronic myelocytic leukemia. 325 50

Although mononuclear cell surface markers are primarily used to determine the lineage and stage of differentiation of leukemias and lymphomas, they can also be helpful in discriminating between some cases of neoplastic and reactive conditions. Peripheral blood lymphocytosis secondary to infection most often shows increased numbers of activated T cells of the suppressor/cytotoxic subset. A few exceptions, such as in pertussis, show predominantly T-helper cells. Although persistent B-cell lymphocytosis is most often associated with neoplastic conditions, B-cell predominant reactive conditions may also occur. Lack of light chain restrictions on B-cell membranes suggests non-neoplastic disorders. Reactive lymphadenopathy most often shows a predominance of T cells with normal to increased T-helper/T-suppressor cell ratios. In addition, normal ratios of kappa/lambda light chain surface immunoglobulin usually occur on B cells of reactive lymph nodes. Benign lymphocytic infiltrates in skin most often show a predominance of activated T-helper cells. Distinguishing reactive from neoplastic dermal infiltrates by mononuclear cell markers can be extremely difficult and may require DNA genotypic analysis. Mononuclear cell markers applied to bone marrow in patients treated for leukemia and other disorders must also be interpreted with caution. The presence of CD10 antigen (CALLA) may herald recurrence of leukemia; however, this determinant is not leukemia-specific and may be found on normal cells. Similarly, lymphoid cells bearing TdT often represent recurrent leukemia, and they must be differentiated from immature nonmalignant TdT-positive cells. Immunologic surface markers must be interpreted together with a careful review of the morphology of the tissues.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Lymphocytic surface markers in lymphoid leukemoid reactions. 328 62

The method to fix single cells in suspension and its application for the detection of TdT-positive cells by flow cytometry are described. In comparison to formalin-methanol fixation, formalin-acetone fixation resulted more formation of aggregated cells which caused non-specific staining. In our assay system 80% cells in human thymus were TdT-positive. Levels of TdT in normal human peripheral blood was 0.5 +/- 0.6% (means +/- 1 S.D., n = 50). A total of 104 patients with leukemia/lymphoma was examined for TdT. TdT-positive cells were detected in ALL (87.5% cases), AML (57.1% cases), CML-BC (58.3% cases) and ML (17.6% cases). Mean channel of fluorescence intensity of the TdT-staining in AML was significantly reduced in comparison with that in ALL. When antigen density of TdT was very low, fluorescence microscopy gave false negative results and flow cytometry could detect this dim fluorescence.
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PMID:Enumeration of terminal deoxynucleotidyl transferase positive cells in leukemia/lymphoma by flow cytometry. 329 65


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