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)

The ability of nitrous oxide to inhibit the in vivo growth of hematological neoplasms was investigated in a rat model for acute myeloid leukemia (BNML). Nitrous oxide, administered in a concentration of 67% with 33% oxygen, resulted in a reduction of spleen and liver weights of approx. 30%, as compared with leukemic rats kept in ambient air. Peripheral white cell counts were also considerably lower in the treated rats. Plasma levels of vitamin B12 were found to be elevated in untreated leukemia, but fell to about normal levels after nitrous oxide exposure. On the contrary, folic acid levels were low in untreated leukemic rats, and significantly higher in animals exposed to nitrous oxide. The observed effects of nitrous oxide appeared to be dose-dependent. The deoxyuridine suppression test performed with leukemic cells became abnormal after nitrous oxide inhalation, in accordance with the effect on normal bone marrow. These results indicate that the interference of nitrous oxide with vitamin B12-related metabolism, which leads to impairment of de novo thymidine synthesis, has the potency to reduce leukemic proliferation in vivo.
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PMID:Nitrous oxide reduces growth of experimental rat leukemia. 658 56

A patient is described who appeared to demonstrate modulation of acute myelogenous leukaemia with vitamin B12 deprivation. Support for this observation was obtained via an in vitro bone marrow blast cell assay. The addition of B12 to this patient's bone marrow in vitro significantly stimulated the colony forming ability of the blast cells. Patients with B12 deficiency have an increased incidence of haematopoietic malignancies and excessive replacement of B12 may in some cases have the potential of accelerating such disorders. Intensive B12 replacement in refractory megaloblastic anaemias should be done with caution.
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PMID:Acute myelogenous leukaemia modulated by B12 deficiency: a case with bone marrow blast cell assay corroboration. 659 92

Acute nonlymphocytic leukemia developed in a 57-year-old woman following adjuvant therapy with melphalan for ovarian carcinoma. Maturation of differentiating marrow myeloid and erythroid precursors was megaloblastic. The serum vitamin B12 level was low, and Schilling test revealed vitamin B12 malabsorption correctable with intrinsic factor. Megaloblastic maturation of the marrow cells was converted to normoblastic following treatment with vitamin B12 and folic acid. However, blast cells persisted in the marrow, and cytogenetic analysis revealed aneuploidy and trisomy 18. In contrast to the marrow blast cells, there was a decline in circulating blast cells following vitamin replacement, suggesting that these cells were capable of maturation but required vitamin B12 for this purpose.
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PMID:Unusual case of acute leukemia. Coexisting acute leukemia and pernicious anemia. 673 67

Association between HLA haplotypes and long survival was investigated in 116 children with acute lymphoblastic leukaemia. It was found that patients with A2 B12 and/or A2 B40 haplotypes survived longer than patients wtihout these two haplotypes. Since all children were treated with transfer factor obtained from their relatives, it is suggested that children possessing A2 B12 or A2 B40 haplotypes may respond better to this type of immunotherapy.
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PMID:HLA haplotypes and long survival in childhood acute lymphoblastic leukaemia treated with transfer factor. 692

Clinical and laboratory findings at the time of diagnosis were correlated with the survival of 242 patients with chronic myelocytic leukemia. Twelve patients with the blastic stage of the disease (blasts greater than or equal to 29%) had a median survival of eight months. Of the nonblastic patients, 28 without the Philadelphia chromosome had a relatively constant mortality averaging 43% per year and a median survival of 13 months, markedly worse than the Ph1-positive group (mortality, 6% in the first year, 17% in the second year, and the 25% per year, with a median survival of 43 months; P less than 0.001). In the latter group of 202 patients, features reflecting the "quantity" of leukemia (leukocyte count, marrow cellularity, and M:E serum B12, different degrees of splenomegaly, presence or absence of symptoms) had weaker or short-term correlations with mortality, while "qualitative" abnormalities (e.g., increased percentage of circulating blast, extramedullary leukemic tumors, major abnormalities of erythropoiesis or platelet production, marked basophilia or eosinophilia) had strong and persistent correlations with mortality. Chromosome abnormalities in addition to the Ph appeared to have a delayed though significant effect on survival. Serum alkaline phosphatase and SGOT levels did not correlate significantly with survival, but major elevations of serum LDH were associated with increased mortality throughout the course of the disease.
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PMID:Prognostic features at diagnosis of chronic myelocytic leukemia. 694 41

Chromosomes of bone marrow from 28 patients with acute nonlymphocytic leukemia (ANLL) (26 with AML, 2 with AMMoL), 19 of whom had chromosome abnormalities, were studied; 11 cases exhibited previously unreported karyotypic abnormalities. The marrows of two cases had 8-21 translocations associated with an iso-X chromosome in the female patient and with 9q13- and a missing Y in the male patient. Usually, AML patients with a 8-21 translocation have been considered to have a good prognosis; however, our cases had rather short survival times. Therefore, the prognosis of AML with an 8-21 translocation but associated with other abnormalities is still not clear. Centromere spreading (CS), which was originally reported in marrow cells of megaloblastic anemia (B12 and folic acid deficiency), was detected in leukemic cells, disappeared during remission, and reappeared on relapse. These findings suggest that CS may be a new type of abnormality in AML. In two patients with atypical hypoplastic anemia and hemolytic anemia, chromosome abnormalities were detected at the anemic stage. One case with CS was associated with atypical hypoplastic anemia and developed AML after 1 year; the other with 48,XY,+i(1q),+3,/12 and -14 had hemolytic anemia and developed AMMoL 3 weeks later. Interestingly, identical clones were detected both before and after the clinical diagnosis of leukemia. These cases strongly support the concept that some chromosome abnormalities precede the clinical manifestations of leukemia. The present study also revealed that lymphocytes in ANLL respond poorly to PHA in the presence of high numbers of blasts but do respond well to mitogens during remission. Therefore, the response of lymphocytes to PHA may serve as one criterion for determining remission.
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PMID:Diagnostic and prognostic significance of chromosome abnormalities in marrow and mitogen response of lymphocytes of acute nonlymphocytic leukemia. 695 Aug 4

The two types of granule in polymorphonuclear neutrophils may have distinct functions. The primary granule enzymes are responsible for killing and digesting ingested micro-organisms while the secondary granule constituents may have regulatory functions outside the cell. This hypothesis is supported by finding that during immune phagocytosis of a yeast, nearly all of the neutrophil's secondary granule vitamin B12-binding protein is lost from the cell and 80% can be accounted for in the medium. Much less of the primary granule enzymes, beta-glucuronidase and acid phosphatase, are lost from the cells and very little can be detected in the medium. Lysozyme is a constituent of both types of granule and its behaviour is intermediate. There is no difference in the release of these granule constituents from chronic granulocytic leukaemia neutrophils compared with normal neutrophils.
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PMID:The discharge of primary and secondary granules during immune phagocytosis by normal and chronic granulocytic leukaemia polymorphonuclear neutrophils. 695 21

The ability of various murine and human cell types to secrete in vitro transcobalamin II (TCII), the vitamin B12 transport protein, was investigated. All cell types tested were found to secrete into the culture medium biologically active TCII molecules, capable of facilitating B12 uptake. The largest amounts of TCII were produced by primary cultures of murine fibroblasts and macrophages. Large quantities of TCII were also secreted by myeloma, erythroid leukemia, and macrophage-like tumor cell lines. Murine thymus cells of T lymphocyte tumors secreted only small quantities of TCII. Mouse monocytes and fibroblasts secreted considerably larger quantities of TCII than did their human counterparts. The data indicate that many cell types have the potential to produce biologically active TCII in vitro. Whether this in vitro potential also reflects in vivo biosynthetic activity is discussed.
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PMID:Production of transcobalamin II by various murine and human cells in culture. 710 16

Six children who developed acute myelomonocytic leukemia presented with a preleukemic syndrome. The incidence of preleukemic presentation of AMML was 17% of children with acute nonlymphocytic leukemia, or 2.9% of all children with acute leukemia at this institution, incidences similar to those in adults. During the preleukemic phase, which lasted from three to 35 months, all children had anemia, all had infectious complications, and three of six had hemorrhagic tendencies. Three received steroids before the diagnosis of AMML, and all had some objective response. Two patients died before receiving therapy for AMML. Four children who received AMML therapy with combinations including cytosine arabinoside and an anthracycline achieved complete remission. Ultimately, all patients died. Clues to diagnosis of preleukemia include unexplained cytopenias, either absolute or functional, peripheral blasts, progressive megaloblastosis with an elevated B12 value, dyserythropoiesis, abnormalities of nuclear segmentation, nonrandom chromosomal alterations, and reduced marrow colony to cluster ratio in vitro. Until there is a highly effective therapy for ANLL, precisely when to treat the child with preleukemia remains uncertain. However, treatment should be started before infectious complications or hemorrhagic tendencies become life-threatening.
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PMID:Preleukemia in children. 720 82

The cyanogen bromide method was applied to the assay of vitamin B12-dependent methyltetrahydrofolate:homocysteine methyltransferase activity in normal and leukemic human hematopoietic cells. Normal peripheral lymphocytes and leukemia cells of lymphoid origin wuch as CLL and ALL, contained higher levels of enzyme activity than did normal human bone marrow cells. Normal granulocytes and leukemia cells of myeloid origin, such as CML in the chronic phase and AML, contained lower enzyme activity. Leukemia cells of CML in blast crisis showed higher mean activity than in the chronic phase of the disease.
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PMID:Vitamin B12-dependent methyltetrahydrofolate: homocysteine methyltransferase activity in normal and leukemic human hematopoietic cells. 747 90


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