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)

Knowing the good penetration of systemic HDara-C into the CNS, we treated with this approach overt meningeal leukemia, either isolated or with bone marrow (BM) disease, in 31 adults: 18 ALL, 4 ANLL, 1 lymphoid blast crisis of CGL (LBC-CGL), and 8 non-Hodgkin's lymphoma (NHL). Treatment consisted of Ara-C, 3 g/m2 i.v. q 12 h, by 3 h infusion for 8 doses, followed by 4 doses at day 21. Complete remitters received consolidation with four monthly 4-dose courses of HDara-C. Additional multidrug consolidation and direct CNS therapy with intrathecal (i.t.) methotrexate (MTX) or Ara-C +/- cranial RT was administered to the 11 remitters last treated. Twenty of 31 patients (64%) achieved CR: 10/10 with isolated meningeal leukemia and 10/21 with concurrent CNS and BM disease. Of the remaining 11 patients, 8 had cerebrospinal fluid (CSF) clearing with persistent BM disease. In all cases but one CNS symptoms resolved promptly. CR median duration was 6 months (range 2 to 20). The main toxicity was myelosuppression requiring intensive support. There was no neurologic toxicity. These results show that systemic HDara-C is highly effective in acute leukemias and NHL with CNS involvement, and suggest the utility of this regimen for sanctuary chemoprophylaxis in patients at high risk for CNS disease.
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PMID:Central nervous system (CNS) leukemia: the role of high dose cytarabine (HDAra-C). 271 52

The Philadelphia (Ph) chromosome usually results from the t(9;22), which causes the physical association of the BCR1 and ABL genes and their function as a single new gene. This precise genomic mutation probably has a significant role in the development of leukemia in humans, but that leukemia may take several forms: chronic myeloid leukemia (CML), acute myeloid leukemia, acute lymphocytic leukemia, and essential thrombocythemia; CML also transforms to a lymphoid or myeloid acute phase. Two models are considered with regard to determinants of this variable hematologic expression of BCR-ABL. The first is variation in the breakpoint site of BCR1. Two breakpoint sites, M-BCR and m-BCR, are known, and their occurrence shows a nonrandom association with the different forms of leukemia. The precise position of the breakpoint within M-BCR may also be important. The second model concerns the role of other genes in determining the leukemic form shown by BCR-ABL. Results are reviewed of a patient who entered blast crisis CML and whose leukemic clones involved ten genetic loci with known leukemic associations. Many of these were probably genetic variants that allowed leukemic proliferations following the initiation of blast crisis. The multiplicity of these genes may obscure the prime determinant of blast crisis, which is unknown at the present time.
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PMID:The variable hematologic expression of the BCR-ABL genomic mutation and its possible determinants. 279 Jul 50

The expression of two myeloid antigens identified by the monoclonal antibodies (McAb) MCS2 (CD13) and MY9 (CD33) was investigated in 136 cases of leukaemia. MCS2 was positive in blast cells of 78 of 88 (88.5%) and MY9 in 51 of 81 (64%) cases of acute myeloid leukaemia (AML) and chronic granulocytic leukaemia in myeloid blast crisis. One or other McAb, or both, were positive in all but 2 (2.3%) of these cases. MCS2 was more sensitive than MY9 to detect blasts of the myeloid lineage due to its most frequent reactivity in the cytoplasm of fixed cells by the immunoperoxidase (IP) technique compared with its membrane expression on cell suspensions by immunofluorescence (IF). MY9 was not suitable for tests on fixed cells. MCS2 was positive by IP but not by IF in 24% of AML, but the reverse was not observed. This suggests that the antigen detected by MCS2 is expressed in myeloblasts first in the cytoplasm and later on the cell membrane, pattern which is similar to that of the early antigens CD3 and CD22 in T and B lineage lymphoblasts, respectively. MCS2 was always positive in FAB types of AML-involving myeloblasts (M1-M4), including cases of undifferentiated morphology (M0), whilst MY9 was more frequently positive in monocytic leukaemia (M5). On the other hand, MCS2 was positive in 4 of 33 cases of acute lymphoblastic leukaemia and MY9 in 1. We conclude that both McAb, particularly MCS2, contribute to the better characterisation of myeloid leukaemias but that other tests are required to clarify the nature of the blasts when unexpected reactivities are observed.
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PMID:Early expression of MCS2 (CD13) in the cytoplasm of blast cells from acute myeloid leukaemia. 290 4

Using a cDNA clone for the beta-subunit of the receptor on human leukocytes that mediates cellular adherence (CD18), we investigated the lineage specificity of beta-subunit mRNA expression in human hematopoietic cells. Relatively high levels of the beta-subunit mRNA transcript were detected in mature peripheral blood leukocytes, including granulocytes and both resting and PHA-activated T lymphocytes. In contrast, relatively low levels of this transcript were observed in EBV-transformed B cells, in the immature Jurkat T cell line, and in chronic myelogenous leukemia myeloblasts and lymphoblasts. The beta-transcript was undetectable in the K562 chronic myelogenous leukemia blast crisis cell line with erythroblastic characteristics and in cultured skin fibroblasts. Two acute myeloid leukemia samples displayed unusually high levels of this transcript, comparable to levels observed in mature PBL. beta-subunit mRNA expression appeared to be primarily confined to leukocytes. In all cells examined the levels of surface beta-Ag expression paralleled levels of beta-mRNA.
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PMID:Expression of the beta-subunit of the human leukocyte adherence receptor depends upon cell type and stage of differentiation. 290 71

We conducted a Phase I-II trial of 4-demethoxydaunorubicin (idarubicin, IDR) in combination with 1-beta-D-arabinofuranosylcytosine (ara-C) in 51 patients with relapsed or refractory acute nonlymphocytic leukemia, acute lymphocytic leukemia, or chronic myelogenous leukemia in blast crisis. Only 1 of 12 patients treated at the first dose level (idarubicin, 10 mg/m2/day for 3 days and ara-C, 25 mg/m2 i.v. bolus followed by 200 mg/m2 continuous infusion daily for 5 days) achieved aplasia and complete remission. The dose of idarubicin was subsequently increased to 10 mg/m2/day for 4 days with the ara-C dose held constant. Complete remission incidence for this dose schedule was: 7 of 31 patients with acute nonlymphocytic leukemia, 0 of 5 patients with acute lymphocytic leukemia, 0 of 1 patient with chronic myelogenous leukemia in blast crisis, and 1 of 2 patients with biphenotypic leukemia. Nonhematological toxicity included nausea, vomiting, mucositis, and abnormal liver function tests. Detailed pharmacological studies were performed to determine whether ara-C altered IDR metabolism or that of its main metabolite, 13-hydroxyidarubicinol or IDR clearance. A high degree of variability among patients was apparent and no consistent effect could be demonstrated. In summary, 9 of 37 patients (24%) with relapsed or refractory ANLL, including 1 patient with biphenotypic leukemia, achieved remission. We conclude that idarubicin in combination with ara-C is an active combination in patients with relapsed or refractory leukemia.
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PMID:4-demethoxydaunorubicin (idarubicin) in combination with 1-beta-D-arabinofuranosylcytosine in the treatment of relapsed or refractory acute leukemia. 291 Apr 65

The iron chelator desferrioxamine (DFO) has been previously shown to be an S-phase inhibitor of cell proliferation. To investigate its potential as an antileukemic drug, we first studied the effects of DFO on the in vitro growth of normal human hematopoietic progenitors (CFU-GM and BFU-E) and clonogenic cells from human leukemic cell lines. Then we evaluated the effects of DFO on progression of leukemia refractory to conventional therapy in two individuals. Micromolar concentrations of DFO determined a dose-dependent inhibition of normal progenitor growth, with inhibitory dose 50% (ID50) for CFU-GM and BFU-E being 6.7 and 5.5 microM/liter, respectively. Marked inhibitory effects were observed on clonogenic cells from HL-60 (ID50 = 1.4 microM/liter) and U-937 (ID50 = 3.6 microM/liter) human leukemic cell lines grown in semisolid medium. When DFO was given intravenously to a patient with lymphoid blast crisis of chronic myelogenous leukemia, a marked reduction in circulating blast count was observed. On the contrary, no in vivo effect was observed in a patient with acute nonlymphocytic leukemia having transfusional iron overload. We conclude that: (a) DFO is an inhibitor of both normal and leukemic myeloid cell proliferation in vitro; (b) our limited in vivo observations and a previous case study suggest that intravenous administration of DFO to patients with normal to low plasma iron may result in leukemic cytoreduction in vivo.
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PMID:Effects of desferrioxamine on normal and leukemic human hematopoietic cell growth: in vitro and in vivo studies. 291 Dec 2

Twenty-five samples of fresh malignant cells of patients with acute leukemia (16 with acute myeloblastic leukemia, five with acute lymphoblastic leukemia, and four with chronic myelocytic leukemia in blast crisis) and of two patients with colon carcinoma were exposed for 1 hr to different concentrations of methotrexate (MTX) or trimetrexate (TMQ). In all samples, TMQ was at least one log more potent than MTX in inhibiting [3H]deoxyuridine incorporation into DNA. Cells relatively resistant in vitro to MTX also displayed decreased sensitivity to TMQ, although TMQ "resistance" was usually much less pronounced. In eight of the 25 leukemia samples, intracellular drug levels after exposure in vitro could also be measured. The intracellular levels of TMQ were 6 to 64 times higher than those of MTX, indicating that the difference in potency of these drugs may be related to the difference in intracellular accumulation. The intracellular levels of both agents varied widely and were not directly related to the degree of DNA synthesis inhibition. There was, however, a clear positive correlation between the intracellular ratio [TMQ]/[MTX] and the deoxyuridine incorporation after exposure to MTX. This observation suggests that 1) intracellular TMQ levels may be used as an internal standard to correct steady state intracellular MTX levels for variations such as cell size, and 2) in analogy to tissue-culture models, decreased intracellular accumulation of MTX may contribute to clinically encountered drug resistance.
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PMID:Effects of methotrexate and of the "nonclassical" folate antagonist trimetrexate on human leukemia cells. 295 24

Activities of five acid glycosidases were examined in leukocytes of 30 healthy persons, 17 patients with chronic myeloid leukemia (CML) and 7 patients with acute myeloid leukemia (AML). In leukocytes of the patients with CML activities of alpha-D-mannosidase, N-acetyl-beta-D-hexosaminidase and beta-D-glucurodase were significantly higher (p less than 0.01) and those of alpha-D-galactosidase and alpha-D-glucosidase were somewhat higher (p less than 0.05) as compared with control leukocytes. Activities of all five glycosidases in leukocytes of patients with AML were within the normal limits. Glycosidase activities were also examined in leukocytes of three groups of patients with CML at different stages of the disease: chronic, progressive and blast crisis. All the enrymes exhibited the highest activity in the first group of patients; the activities of these enxymes in the second group were lower and those in the third group were close to normal. When CML leukocytes were fractionated using the Ficoll-verografin method, the activities of the enzymes in the interface fraction (unmatured cells) were higher than those in the bottom fraction (matured granulyocytes). These data suggest that the increased glycosidase activity in CML cells is due to the presence of the population of unmatured granulocytes which are distinct from blast cells.
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PMID:[Acid glycosidases in leukocytes of patients with chronic and acute myeloid leukemias]. 301 May 66

The techniques of transmission electron microscopy (TEM), including ultrastructural myeloperoxidase cytochemistry (MPO), and immunological marker analysis, have been used to classify 58 "difficult" cases of acute leukemia where a precise diagnosis could not be made on the basis of conventional light microscopy and cytochemistry. TEM with MPO proved most valuable in characterizing 15 cases of acute myeloid leukemia and its variants, as well as defining complex cellular subpopulations in 11 cases of chronic myeloid leukemia in blast crisis. Immunological marker studies provided conclusive evidence of lymphoid differentiation in 18 cases of acute lymphoblastic leukemia and related disorders. In addition, the combined techniques were used to document 14 cases of terminal transferase-positive acute myeloid leukemia. This study demonstrates that these 2 techniques provide overlapping and complementary information for accurate diagnosis and classification of morphologically difficult hematological malignancies.
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PMID:Characterizing "difficult" acute leukemias. A combined electron microscopic and immunological marker study. 301 25

The ability to transplant bone marrow makes it possible to treat patients with hematologic malignancies with doses of systemic radiotherapy or chemotherapy that would ordinarily result in fatal myelosuppression. With this approach, some otherwise incurable patients can be treated successfully. For most hematologic malignancies (acute nonlymphocytic leukemia, acute lymphocytic leukemia, chronic myelogenous leukemia, and malignant lymphoma), if transplantation is delayed until patients have end-stage disease (drug-resistant relapse) or blast crisis, approximately 10 to 20% of patients can be saved. If transplantation is carried out earlier in the course of disease, the outcome improves considerably. Some of the major limitations of marrow transplantation are the need for an appropriate source of marrow, the severe myelosuppression seen in the immediate posttransplant period, the complications of graft-v-host disease (GVHD), and disease recurrence. The use of autologous marrow and the formation of a national donor registry may make transplantation more widely applicable. The availability of growth factors can hasten hematopoietic recovery, making the immediate posttransplant period safer. New immunosuppressive regimens and T-cell depletion of donor marrow can diminish the impact of GVHD. The need for better preparative regimens persists and has emerged as the major requirement for continued progress in marrow transplantation.
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PMID:Marrow transplantation for hematologic malignancies: a brief review of current status and future prospects. 305 5


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