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 performed an immunohistochemical analysis of frozen sections from testicular biopsies from 23 children with acute lymphoblastic leukemia. Eleven cases were infiltrated by leukemia. Tumor cells were immunostained by a panel of antibodies that identified CD10, CD43, CD19, CD3, CD7, and MHC class I and II. The immunoreactivity of normal testicular components was also studied. Normal testis showed no CD10 reactivity. Wide variation in the number of stromal macrophages identified by CD11c was found. Transferrin receptor (CD71) was expressed by some stromal macrophages, by seminiferous tubules, and by Leydig cells. B lymphocytes were absent from the testicular stroma but small numbers of T lymphocytes were consistently present. MHC class I and II were expressed by most stromal cells but not by seminiferous tubules.
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PMID:An immunohistochemical study of testicular biopsies in childhood acute lymphoblastic leukemia: reactivity of normal testicular components and leukemic infiltrates. 128 64

We studied the biological characteristics of CD7+ acute myelogenous leukaemia (AML). We diagnosed nine out of 88 consecutive AML cases as CD7+ AML based on myeloperoxidase positivity and surface antigen expression. In eight of these nine cases more than 20% of leukaemic blasts were found to coexpress both CD7 and a myeloid-associated antigen, CD33, by a two-colour flow-cytometric assay, while in the remaining case more than 90% of blasts were positive for CD7 and myeloperoxidase. CD7+ AML was most frequently observed in M1 among AML subtypes according to the FAB classification. An early stage-specific antigen, CD34 was also expressed on leukaemic blasts from eight of these nine cases. Neither the T-cell receptor (TcR)-beta nor the TcR-gamma gene was clonally rearranged in any of the cases. We then studied the proliferative responses to stimulation by various growth factors. Among interleukin-3 (IL-3), granulocyte/macrophage colony-stimulating factor (GM-CSF), and granulocyte-CSF (G-CSF), IL-3 showed the strongest stimulatory effect on DNA synthesis and leukaemic blast colony formation in 8/9 and 6/8 CD7+ AML cases examined, respectively. On the other hand, the strongest stimulatory effect exerted by IL-3 on blast colony formation was observed in only six out of the 33 CD7- AML cases examined. Furthermore, CD7+ AML blasts could proliferate in response to stem cell factor (SCF); SCF alone showed stimulatory effects on blast colony formation (7/8 cases), and in 5/7 SCF-responding cases, stimulatory effects of SCF were more potent than those of IL-3. In addition, SCF enhanced blast colony formation synergistically with IL-3 in four of these seven cases. These data suggest that progenitor cells of CD7+ AML may possess the biological properties characteristic of immature haematopoietic stem cells.
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PMID:Biological characteristics of CD7 positive acute myelogenous leukaemia. 128 77

From May 1985 to June 1990, 94 newly diagnosed cases of acute myelogenous leukemia (AML) were treated at the Institut Gustave-Roussy, of which four (4.3%) demonstrated mixed cell lineage. All these cases were morphologically and cytochemically considered as myelogenous leukemias according to the FAB classification. Immunophenotyping revealed in all four cases that the blast population had T-lymphoid (CD2, CD5, CD7 and cytoplasmic CD3) markers. In three of these cases, blast cells co-expressed myelogenous CD13 and CD33 markers. Cytogenetic analysis of the blast cells revealed a normal karyotype in all cases. The response to therapy has been poor. The two patients initially treated with a regimen usually used for AML did not achieve complete remission. By contrast, in three cases, complete remission was obtained with a drug combination used for lymphoblastic leukemia (in one case after failure of first line AML regimen). Only one patient remained disease-free for more than 18 months. We conclude that this form of leukemia is a distinct biological and clinical entity and may benefit form alternative therapy.
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PMID:Acute myelogenous leukemia with T-cell features. 130 36

YT cells, originally reported as a natural-killer-like (NK-like) lymphoid cell line, were investigated for Epstein-Barr virus (EBV) genome, gene rearrangement for T-cell receptor (TCR), phenotype and function. The YT cells of the original batch (YT-0) and two subclones (YT2C2 and YTC3) expressed EBV-associated nuclear antigen, and the BamHI-digested DNA showed the 3.4 kb hybridizing band with the BamHIW probe of EBV DNA in Southern blot analysis. When tested with latent-infection membrane protein probe, an identical hybridizing band was shared, indicating that all three sources of YT cells were of monoclonal derivation in terms of the terminal repeat junctional structure of EBV DNA, and that the original YT cells had been infected with EBV before the isolation of the two subclones. The cell-surface antigen analysis revealed the expression of CD7, CD28, CD30, CD45R0, TLiSA and S6F1 antigen besides the originally recorded CD25, CD56 and HLA-DR antigen. Gene rearrangement analysis showed the germ-line genotype, including TCR gamma and delta as well as beta chain. The Northern blot study using the CD3 epsilon and CD3 delta chain gene probes revealed CD3 epsilon, but not CD3 delta RNA. The YT-0 cells exhibited NK and antibody-dependent cellular cytotoxicity activity, but the YT2C2 and YTC3 cells did not. It was not resolved whether the fresh neoplastic NK-like cells of the YT-cell donor carry EBV genome, but YT cells, the first lymphoid cell line found to have EBV genome and non-B lymphoid properties, are valuable for investigating the relationship between EBV and human non-B lymphoid hematopoietic cells.
Leukemia 1992 Feb
PMID:Detection of Epstein-Barr virus genome in natural-killer-like cell line, YT. 131 26

The immunophenotype of leukaemia cells from 60 patients with acute myeloid leukaemia (AML) was analysed with the APAAP technique using a panel of anti-myeloid and lymphoid associated monoclonal antibodies (McAb). Cells from all cases, including three with negative cytochemical features, were labelled by at least one of the anti-myeloid McAb CD13, anti-myeloperoxidase (anti-Mpo), and/or CD14. The most sensitive marker was CD13, since it was positive in 90% of cases. In two out of three AML cases defined as M0-AML, CD13 was expressed in the cytoplasm but not on the membrane; in these three cases peroxidase (Mpo) was not detected by conventional cytochemistry, but could be demonstrated in all of them using the McAb anti-Mpo. The simultaneous expression of CD14 and CD68 McAb was often confined to the M4 and M5 FAB AML subtypes (92% cases) as compared to the others: M1, M2, M3 (18% cases). Lymphoid antigens were rarely positive (TdT+: 13%, CD7+: 15%, CD19+: 5%) and none of the AML cases were CD3+ or CD10+. By contrast, CD4 was expressed in blasts from 44% of cases and this was not restricted to AML with a monocytic component (M4, M5) but also found in other subtypes. There were no significant differences in the clinical or prognostic features according to the positivity or negativity with TdT and CD4. By contrast, expression of CD7 was associated with refractoriness to the treatment or short complete remission duration, although the number of patients is too small to draw firm conclusions. Our findings support the clinical and diagnostic relevance of immunophenotypic studies in AML.
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PMID:The value of detecting surface and cytoplasmic antigens in acute myeloid leukaemia. 132 89

Between 1983-1988 bone marrow samples obtained from 195 peroxidase-negative leukemia patients were analyzed for their surface antigens. Thirteen of these patients (6.7%) had myelomonocytic-positive and lymphoid-negative antigens. These leukemic cells reacted with CD13 in eight patients, CD33 in seven, CD11 in six and CDw41 in two. In none of these patients did the leukemic cells react with CD1, CD2, CD3, CD4, CD5, CD8, CD10, CD19 or CD20. Leukemic cells from two patients were reactive with CD7. These leukemic cells demonstrated L2 morphology in 11 patients and L1 morphology in one patient. The leukemic cells from the final patient were diagnosed as those of leukemic transformation of myelodysplastic syndrome. Chromosomal abnormality was observed in approximately half of the patients examined (6/10). Cytochemical analysis revealed that the leukemic cells were negative for periodic acid Schiff stain but positive for acid phosphatase. The prognosis of these patients was markedly poor as compared to acute lymphocytic leukemia or typical peroxidase-positive nonlymphocytic leukemia. Complete remission was induced in only 30% of patients and duration of survival was short (4.7 months). This suggests that myelomonocytic antigen-positive peroxidase-negative acute leukemia is a distinct type of leukemia and may require more aggressive therapy to improve survival.
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PMID:Peroxidase-negative and myelomonocytic antigen-positive acute leukemia. 132 47

The epigenetic phenomenon could play a role in the interaction between chromatin and DNA-binding enzymes, allowing us to consider an association between the phenomenon and gene rearrangement. The correlation between methylation status and rearrangement of the T-cell receptor (TCR) beta chain gene in leukemia cells obtained from patients with acute myeloid leukemia (AML) was examined. All of the AML patients with a TCR-beta rearrangement had hypomethylated CCGG sequences within the J beta 1 region on the rearranged allele, while the germline allele had completely methylated CCmeGG sequence in this region, indicating a strong association between hypomethylation status and rearrangement of the TCR beta chain gene. In the DNA from AML patients with or without a TCR-beta rearrangement, the C beta 2 region contained completely methylated CCmeGG sequences, even though they express T-cell-associated antigens, including CD7; this pattern is quite different from that observed in T-cell neoplasias. Moreover, some AML patients showed a TCR-beta rearrangement without the presence of immunoglobulin heavy-chain gene rearrangement, suggesting that TCR beta chain gene involvement in AML is required for unknown factors other than common recombinase activity.
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PMID:T-cell receptor beta chain gene rearrangement in acute myeloid leukemia always occurs at the allele that contains the undermethylated J beta 1 region. 133 Feb 97

In order to investigate the role of T-cell receptor (TcR)-delta and TcR-gamma gene rearrangements and/or deletions in acute myeloid leukemia (AML) coexpressing T-cell-associated antigens (i.e. CD2 and/or CD4 and/or CD7), we examined blasts from a selected group of 56 AML cases (25 children, 31 adults) coexpressing either of these antigens without cytoplasmic CD3 expression. Forty-four typical AML cases (7 children, 37 adults) without T-cell associated antigens were further studied as controls. Germline configuration of the TcR-delta gene was observed in 91 out of the total of 100 AML cases investigated. Eight of nine cases with rearranged or deleted TcR-delta genes coexpressed T-cell-associated antigens. Blast cells of 7/9 cases were classified as FAB M1, two as FAB M2. In six of these cases TcR-gamma gene rearrangements were also detected. TcR-delta alterations were predominantly found in children whose blasts coexpressed T-lymphoid associated antigens (6/25, 24%), but were rarely detected in adult AML with or without coexpression of T-cell antigens (2/31 and 0/37, respectively).
Leukemia 1992 Dec
PMID:Rearrangements of T-cell receptor delta, gamma and beta genes in acute myeloid leukemia coexpressing T-lymphoid features. 133 55

The study of new therapeutic approaches for refractory human leukemia has been hampered by the lack of relevant in vivo models with disseminated disease, particularly T acute lymphoblastic leukemia (T-ALL). In the present study we evaluated methods for establishing and therapy of a human T-ALL cell line (MT-ALL) in 73 SCID mice. MT-ALL is a T-cell receptor alpha/beta +, CD3+, and CD7+ leukemia cell line, derived from a patient with refractory disease and early death. Injection of 5 x 10(7) MT-ALL cells i.v. caused disseminated human leukemia in hematopoietic and nonhematopoietic organs in 100% of SCID mice (n = 9) leading to death or terminal disease at 65 to 70 days after a uniform clinical course. To study possible therapeutic approaches for disseminated leukemia we utilized an immunotoxin, DA7, constructed by chemically linking the mouse IgG2b anti-CD7(3A1E) monoclonal antibody which recognizes a pan-T-cell marker expressed on almost all T-cell leukemias to deglycosylated ricin A-chain, a catalytic plant toxin and inhibitor of protein synthesis. Administration of DA7 led to greater than 5 log kill of clonogenic MT-ALL cells in vitro and selectively inhibited protein synthesis. DA7 was administered to mice at a dose of 10 micrograms/mouse/day for 5 consecutive days starting 8 days after i.v. inoculation of leukemia. The immunotoxin therapy resulted in significant long term survival over 348 days compared to untreated or control mice treated with anti-CD7 antibody and deglycosylated ricin A-chain which were all dead by day 70 (P less than 0.001). Even after more than 11 months there was no evidence of disease in 82% of the DA7 treated animals. SCID mice given i.p. injections (n = 9) developed an i.p. tumor mass but demonstrated metastasis outside the peritoneum with disseminated leukemia in hematopoietic and nonhematopoietic organs, a finding different from most conventional nude mouse models. The leukemia was fatal in 100% and killed the animals at 68-95 days. SCID mice given i.p. injections of MT-ALL completely responded to therapy with DA7, resulting in survival of 100% of the animals (n = 10) at 216 days (P less than 0.001 compared to untreated animals). Anti-CD7 antibody, deglycosylated ricin A-chain, and a control anti-melanoma immunotoxin (IND1-RTA) showed no therapeutic effect. We conclude that DA7 is an effective in vivo therapeutic agent against human MT-ALL in the SCID mouse system, suggesting potential usefulness for therapy of humans with poor prognosis T-cell leukemia.
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PMID:Successful treatment of human acute T-cell leukemia in SCID mice using the anti-CD7-deglycosylated ricin A-chain immunotoxin DA7. 137 Oct 92

Clinical and cytological features of CD7 positive acute leukemias with biphenotypic characteristics in childhood were documented. From 87 patients with CD7+ acute leukemias, nine patients were selected on the basis of the biphenotypic expression of T-lymphoid and myelomonocytic antigens. The blasts of these patients expressed cell surface CD7, cytoplasmic CD3 and cytoplasmic CD13. In addition to these antigens, surface CD13 was also expressed after short term culture without any mitogens or stimulators. The double PAP method for detecting cytoplasmic antigens (CD3, CD13, beta F1, delta TCS1) was employed in this study. The average age of these patients was higher (10.2 y/o) than patients with common ALL. Mediastinal masses were observed in 4 of 9 patients. They were treated according to the diagnoses based on conventional hematological methods and surface antigen expression. In all 9 patients, complete remission was achieved, however, early relapse was noticed in 7. This study suggests that the leukemia cells of these patients may be derived at an early stage during the differentiation of multipotential hematopoietic stem cells. New therapeutic approaches are necessary to improve the outcome of such T/M biphenotypic leukemias.
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PMID:[Clinical and cytological features of CD7 positive biphenotypic leukemias]. 137 85


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