Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023467 (acute myeloid leukemia)
 35,200 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A large number of monoclonal antibodies (McAbs) directed against components on myeloid (granulocytic/monocytic) cells have been generated. Individual McAbs were identified which are selectively reactive with antigenic determinants expressed by myeloid cells at specific stages of differentiation in a lineage-restricted fashion. The composite phenotype obtained by a combination of antimyeloid McAbs allows for a precise definition of the normal or malignant cell type under investigation. Cell binding studies on normal and leukemic cells and the biochemical characterization of the antigens provided the basis for a grouping of those antimyeloid McAbs into clusters of differentiation (CD). The reactivity patterns of CD11, CD13, CD14, CD15, and CD33 McAbs and the characteristics of the respective antigens are reviewed. These CD McAbs distinguish leukemic cells of myeloid from those of lymphoid origin. The monocytic nature of AML cells can be recognized by CD14 McAbs, whereas the other CD McAbs react with both monocytic and nonmonocytic types of acute myeloid leukemia. The expression of these differentiation antigens is not concordant with the morphological-cytochemical French-American-British (FAB) classification of leukemia; nevertheless, tendencies for agreement are apparent. If used in combination, FAB typing and immunophenotyping could provide complementary information. Their potential use for mapping of myeloid differentiation and for cell type recognition in leukemia phenotyping demonstrates the utility of antimyeloid CD McAbs for biological or clinical investigations. The diagnostic value of antimyeloid McAbs is enhanced if the reagents are included in a panel of McAbs standardized for routine immunophenotyping.
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PMID:Classification of acute myeloid leukemias--a comparison of FAB and immunophenotyping. 331 33

Two patients with acute nonlymphocytic leukemia (ANLL) (FAB-M4) and t(6;9)(p23;q34) are described. Immunological marker analysis revealed a phenotype of HLA-DR+/partly terminal deoxynucleotidyl transferase (TdT)+/CD13+ in both cases and CD33 positivity in one. The expression of CD13 and CD33 by TdT-positive cells was demonstrated by double immunofluorescence staining. Although it has been postulated that TdT plays a role in gene rearrangement, Southern blot analysis performed in one leukemia revealed that both the T cell receptor beta chain genes and the immunoglobulin heavy chain genes were in germ line configuration. Since we could not detect CD13+/TdT+ cells and CD33+/TdT+ cells in control bone marrow samples, double marker analysis was used to detect low numbers of residual leukemic cells during follow-up of one patient. A gradually increasing percentage of CD33+/TdT+ cells was detected in the bone marrow in a period of 6 months before hematological relapse. Although the t(6;9) may not be correlated to a specific French-American-British subtype, it may be associated with TdT-positive ANLL. Since TdT-positive ANLL seems to have a poor outcome, detection of TdT expression in ANLL patients is particularly important for diagnostic purposes. In addition, our results indicate that double immunological marker analysis for a myeloid marker and TdT allows detection of residual disease during follow-up.
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PMID:Translocation (6;9) may be associated with a specific TdT-positive immunological phenotype in ANLL. 334 92

The antigen defined by MCS-2 monoclonal antibody (mAb) was characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of surface and internally labeled cells. Surface iodination revealed that MCS-2 antigen on the surfaces of acute myelogenous leukemia cells, HL-60 cells, and polymorphonuclear leukocytes (PMN) had the same molecular weight (Mr 150,000) and that their autoradiographic bands were also the same. Internal labeling of HL-60 cells with [35S]methionine followed by immunoprecipitation revealed two bands whose molecular weights were 150,000 and 130,000. HL-60 cells gave stronger bands than did PMN. The intensity of the Mr 130,000 band became weaker, when internally pulse-labeled cells were cultured in the absence of labeled methionine, suggesting that Mr 130,000 glycoprotein was a precursor protein of Mr 150,000 glycoprotein. MCS-2 mAb precipitated two bands from tunicamycin-treated HL-60 cells whose apparent molecular weights were 100,000 and 110,000. When cells were cultured with MCS-2 mAb, expression of the antigen decreased rapidly (within 10 min). The degree of suppression was more prominent in PMN than in acute myelogenous leukemia and in myelomonocytic cell lines. Reexpression of MCS-2 antigen by PMN after removal of the mAb from the culture medium was not observed, but it occurred rapidly in myelomonocytic cell lines, although it was blocked by pretreatment of the cells with cycloheximide. These findings suggested that the less-marked suppression of MCS-2 antigen expression by cell lines was due to its greater synthesis by these cells. These findings suggested that MCS-2 mAb reacted with identical molecules, which were recognized by other mAbs belonging to CD13. Furthermore, modulation of MCS-2 antigen was observed by MCS-2 mAb itself.
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PMID:Biochemical and functional characterization of MCS-2 antigen (CD13) on myeloid leukemic cells and polymorphonuclear leukocytes. 347 35

In the past, studies on CD34+ cells have been based on the use of monoclonal antibodies conjugated with different fluorochromes that show different fluorescence intensity and yield variable results. Moreover, most of these studies have neither specifically focused on adult human BM samples nor have they used combinations to explore specifically the phenotype of myeloid committed CD34+ cells. The aim of the present study has been to characterize the normal human CD34+ precursor cells from adult BM in order to identify missing or extremely rare phenotypes that can be used for detecting minimal residual disease (MRD) in patients with AML. For this purpose we have utilized the fluorochrome conjugates that provide the most sensitive signals for identifying low antigenic expression, and the technique has been adapted to the characterization of cells present at very low frequencies. Normal human BM samples from 13 adult healthy volunteers have been analyzed using triple stainings at flow cytometry. The mean percentage of CD34+ cells detected was 0.72 +/- 0.33%; these cells displayed an heterogeneous light-scatter distribution. Most CD34+ cells coexpressed CD38 (96.7 +/- 5.7%), HLADR (81.6 +/- 14.0%), CD33 (84.7 +/- 18.3%), CD13 (84.6 +/- 16.2%) and CD71 antigens (65.5 +/- 9.1%). In addition, almost half of CD34+ cells were CD117+ (60 +/- 26.8%). Only a small proportion of CD34+ cells coexpressed CD4 (15.5 +/- 11.7%, CD36 (31.7 +/- 6.2%), CD61 (16.3 +/- 12.9%), CD41 (6.5 +/- 5.5%) or the lymphoid associated markers CD10 (18.6 +/- 11.8%) and CD19 (12.3 +/- 13.2%). Reactivity for the CD15 antigen was observed in a small population of CD34+HLADR+ cells (11.6 +/- 11.2%) although its intensity of expression was lower than that of the more mature granulocytic cells. No CD34+ cells displayed CD14, CD65, CD20, strong CD22, CD3 and CD56 antigens. Accordingly, most adult bone marrow CD34+ cells appeared to be committed to the myeloid lineage (CD13+/CD33+) and displayed an intermediate-to-large FSC/SSC while the lymphoid-committed CD34+ cells (CD19+, CD10+) were in a minority with low FSC/SSC values. By triple marker stainings several phenotypes of CD34+ precursor cells were found to be either undetectable or present at very low frequencies (< 1 x 10(-3)) in the normal human adult bone marrow. These data may be of great value for defining leukemia 'associated' phenotypes used to detect minimal residual disease in adult acute leukemia patients.
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PMID:Phenotypic analysis of CD34 subpopulations in normal human bone marrow and its application for the detection of minimal residual disease. 747 81

The expression of the pluripotent stem cell antigen CD34 was evaluated at diagnosis in forty-five adult patients with de novo ALL. Comparison of clinical and hematological features between CD34 positive (24/45) and CD34 negative (21/45) patients showed that the former were of older age, had more pronounced lymphoid organ involvement and higher serum LDH levels. Immunophenotypic analysis of marrow blast cells revealed a significant predominance of the 'null' phenotype in the CD34 positive group, together with a strong expression of the VLA-4 and VLA-5 integrins (fibronectin receptors). CD34 positive ALL were also more frequently associated with either aberrant myeloid-related antigens (CD13, CD33) or the P-gp/MDR-1 phenotype. Only 11 out of 24 (45%) CD34 positive patients achieved complete remission after induction chemotherapy, compared to 20/21 (95%) CD34 negative cases. Furthermore, survival was significantly shorter in the CD34 positive group (6.6 mo. vs 13.5 mo.). These results suggest that in ALL, as in AML, CD34 positivity may predict a poor prognosis.
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PMID:CD34 expression in adult acute lymphoblastic leukemia. 749 52

Of 235 consecutive patients with de novo acute myeloid leukemia (AML), clonal chromosomal abnormalities were detected in 151 (64%) of them. Twenty-four of the 71 patients with M2 AML had t(8;21), 35 of the 36 M3 patients had t(15;17), and 11 of the 45 M4 leukemia disclosed inv(16). Six of the eight patients with 11q23 abnormality had M4 or M5 subtype of leukemia. The incidence of t(15;17) and t(8;21) was higher in our patients than in patients from most Western countries. Immunophenotyping was performed on 197 patients. Patients with t(15;17) were associated with negativity to HLA-DR, CD11b, and CD34. Patients with t(8;21) expressed CD13 and CD33 less frequently than other patients, but all showed CD15 positivity. Coexpression of lymphoid-associated antigens on the leukemic blasts was detected in 52 patients (26%), including all 7 patients with t(9;22), 3 of the 8 patients with t/del(11)(q23), 2 of the 25 patients with t(15;17), and 2 of the 22 patients with t(8;21). Seven (35%) of the 20 patients coexpressing lymphoid markers showed immunoglobulin heavy chain or T-cell receptor beta-chain gene rearrangements, while only 2 (4%) of the 53 patients without lymphoid antigen expression did so. Patients with inv(16), t(8;21), and t(15;17) had a better prognosis than other patients. Of all surface antigens tested, only CD15, CD11b, and HLA-DR were of prognostic value: CD15 with a higher complete remission (CR) rate and CD11b or HLA-DR with a shorter CR duration. N-ras mutations were detected in 7 (18%) of the 40 patients in the study, including two of the three patients with inv(16). This study demonstrated differences in clinical features, immunophenotypes, and genotypes among different cytogenetic subgroups.
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PMID:Correlation of cytogenetic results with immunophenotype, genotype, clinical features, and ras mutation in acute myeloid leukemia. A study of 235 Chinese patients in Taiwan. 749 45

A 75-year-old man developed a cluster of differentiation (CD)4-positive but human T-cell lymphotropic virus type I (HTLV-I)-negative T lymphoid neoplasm with overwhelming cutaneous involvement and mild thrombocytosis. Twelve courses tetrahydropyranyl adriamycin, cyclophosphamide, vincristine and prednisone (THP-COP) combination chemotherapy led him to complete remission. After four months of complete remission, however, atypical immature cells (blasts) appeared in peripheral blood and bone marrow. Surface marker analysis revealed the blasts to be CD2-, CD3-, CD4-, CD5-, CD7+, CD8-, CD10, CD13 +/-, CD19-, CD20-, CD25-, CD33+ and human leukocyte antigen-DR (HLA-DR+). Staining for myeloperoxidase, esterases, PAS and platelet peroxidase were all negative. The patient was diagnosed as having both CD7 and CD33 positive acute myeloid leukemia (AML). The relation between the T cell lymphoid neoplasm and AML was not clear. Thrombocytosis became more marked after acute leukemia occurred and the platelet count varied in parallel with the blast cell count in peripheral blood. When the leukemic cell count was high, thrombopoietic activity could be detected in the serum. In addition, conditioned medium obtained from primarily-cultured blasts had detectable thrombopoietic activity, which implied the blasts directly to produce a thrombopoietic factor(s). Analysis of the serum concentration for cytokines with associated thrombopoietic activity indicated that the blasts possibly produced a thrombopoietic factor(s) distinct from interleukin (IL)6, IL3, leukemia inhibitory factor (LIF), erythropoietin and granulocyte macrophage-colony stimulating factor. To our knowledge, this is the first reported case of an acute myeloid leukemia with marked thrombopoiesis (more than 2000 x 10(3)/microliter of maximum platelet count in peripheral blood.
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PMID:Acute myeloid leukemia possibly producing thrombopoietic factor(s). 750 2

A method for automatic lineage assignment of acute leukemias was developed. Input are eight list mode data files acquired with a FACScan flow cytometer. For each cell, four parameters are measured: forward light scatter, orthogonal light scatter, fluorescein fluorescence, and phycoerythrin fluorescence. Eight data files are acquired in the following sequence: unstained, isotype controls, CD10/CD19, CD20/CD5, CD3/CD22, CD7/CD33, HLADR/CD13, and CD34/CD38. First, each of the data files 3 to 8 are clustered independently employing an algorithm based on nearest neighbors. Next, the clusters are associated across the data files to form cell populations, using the assumption of light scatter invariance across tubes for each population. The mean positions of each cell population are fed into a decision tree. The decision tree first identifies normal cell populations, i.e., monocytes, neutrophils, eosinophils, basophils, NK cells, T-lymphocytes, and B-lymphocytes. After elimination of the normal cell populations from the data space, the residual cell populations are classified as B-lineage ALL, T-lineage ALL, AML, AUL, B-CLL, or unknown. The effectiveness of this novel approach is shown with case studies of B-lymphoid, T-lymphoid, and Myeloid acute leukemias.
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PMID:Automatic lineage assignment of acute leukemias by flow cytometry. 750 22

The gene expression of myeloperoxidase (MPO), CD3 epsilon, and CD3 delta molecules, the gene rearrangement of T-cell receptor (TCR) delta, gamma, and beta and immunoglobulin heavy (IgH) chain, and the expression of cell-surface antigens were investigated in seven cases of CD7+ CD5- CD2- and four cases of CD7+ CD5+ CD2- acute lymphoblastic leukemia or lymphoblastic lymphoma (ALL/LBL) blasts, which were negative for cytochemical myeloperoxidase (cyMPO). More mature T-lineage blasts were also investigated in a comparative manner. In conclusion, the CD7+ CD5- CD2- blasts included four categories: undifferentiated blasts without lineage commitment, T-lineage blasts, T-/myeloid lineage blasts, and cyMPO-negative myeloblasts. The CD7+ CD5+ CD2- blasts included two categories; T-lineage and T-/myeloid lineage blasts. The 11 cases were of the germ-line gene (G) for TCR beta and IgH. Four cases were G for TCR delta and TCR gamma. The others were of the monoclonally rearranged gene (R) for TCR delta and G for TCR gamma or R for both TCR delta and TCR gamma. The expression or in vitro induction of CD13 and/or CD33 antigens correlated with the immaturity of these neoplastic T cells, since it was observed in all 11 CD7+ CD5- CD2- and CD7+ CD5+ CD2-, and some CD7+ CD5+ CD2+ (CD3- CD4- CD8-) cases, but not in CD3 +/- CD4+ CD8+ or CD3+ CD4+ CD8- cases. CD3 epsilon mRNA, but not CD3 delta mRNA, was detected in two CD7+ CD5- CD2- cases, while mRNA of neither of the two CD3 molecules was detected in the other tested CD7+ CD5- CD2- cases. In contrast, mRNA of both CD3 epsilon and CD3 delta were detected in all CD7+ CD5+ CD2- cases, indicating that CD7+ CD5- CD2- blasts at least belong to T-lineage. The blasts of two CD7+ CD5- CD2- cases with entire germ-line genes and without mRNA of the three molecules (MPO, CD3 epsilon, and CD3 delta) were regarded as being at an undifferentiated stage prior to their commitment to either T- or myeloid-lineage. The co-expression of the genes of MPO and CD3 epsilon in a CD7+ CD5- CD2- case MPO, CD3 epsilon, and CD3 delta in a CD7+ CD5+ CD2- case suggested the presence of some overlapping phase for T- and myeloid-lineage commitment during immature stages of differentiation. This helps understand the conversion of some T-ALL/LBL cases to acute myeloblastic leukemia (AML).(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Lineage determination of CD7+ CD5- CD2- and CD7+ CD5+ CD2- lymphoblasts: studies on phenotype, genotype, and gene expression of myeloperoxidase, CD3 epsilon, and CD3 delta. 751 45

We have identified and characterized a previously unrecognized form of acute leukemia that shares features of both myeloid and natural killer (NK) cells. From a consecutive series of 350 cases of adult de novo acute myeloid leukemia (AML), we identified 20 cases (6%) with a unique immunophenotype: CD33+, CD56+, CD11a+, CD13lo, CD15lo, CD34+/-, HLA-DR-, CD16-. Multicolor flow cytometric assays confirmed the coexpression of myeloid (CD33, CD13, CD15) and NK cell-associated (CD56) antigens in each case, whereas reverse transcription polymerase chain reaction (RT-PCR) assays confirmed the identity of CD56 (neural cell adhesion molecule) in leukemic blasts. Although two cases expressed CD4, no case expressed CD2, CD3, or CD8 and no case showed clonal rearrangement of genes encoding the T-cell receptor (TCR beta, gamma, delta). Leukemic blasts in the majority of cases shared unique morphologic features (deeply invaginated nuclear membranes, scant cytoplasm with fine azurophilic granularity, and finely granular Sudan black B and myeloperoxidase cytochemical reactivity) that were remarkably similar to those of acute promyelocytic leukemia (APL); particularly the microgranular variant (FAB AML-M3v). However, all 20 cases lacked the t(15;17) and 17 cases tested lacked the promyelocytic/retinoic acid receptor alpha (RAR alpha) fusion transcript in RT-PCR assays; 12 cases had 46,XX or 46,XY karyotypes, whereas 2 cases had abnormalities of chromosome 17q: 1 with del(17)(q25) and the other with t(11;17)(q23;q21) and the promyelocytic leukemia zinc finger/RAR alpha fusion transcript. All cases tested (6/20), including the case with t(11;17), failed to differentiate in vitro in response to all-trans retinoic acid (ATRA), suggesting that these cases may account for some APLs that have not shown a clinical response to ATRA. Four of 6 cases tested showed functional NK cell-mediated cytotoxicity, suggesting a relationship between these unique CD33+, CD56+, CD16- acute leukemias and normal CD56+, CD16- NK precursor cells. Using a combination of panning and multiparameter flow cytometric sorting, we identified a normal CD56+, CD33+, CD16- counterpart cell at a frequency of 1% to 2% in the peripheral blood of healthy individuals. Our studies suggest that this form of acute leukemia may arise from transformation of a precursor cell common to both the myeloid and NK cell lineages; thus we propose the designation myeloid/NK acute leukemia. Recognition of this new leukemic entity will be important in distinguishing these ATRA-nonresponsive cases from ATRA-responsive true APL.
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PMID:HLA-DR-, CD33+, CD56+, CD16- myeloid/natural killer cell acute leukemia: a previously unrecognized form of acute leukemia potentially misdiagnosed as French-American-British acute myeloid leukemia-M3. 752 45


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