Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023473 (chronic myeloid leukemia)
 18,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Extracts of human normal and leukemic leukocytes contain an enzyme that catalyzes a transfer of labeled methyl carbon from N5-[14C]methyltetrahydrofolate to tryptamine. Evidence is presented that this reaction is not attributable to a methyltransferase but to the following reaction sequence: (a) an oxidation of N5-[14C]methyltetrahydrofolate to N5, N10-[14C]methylenetetrahydrofolate that is catalyzed by N5, N10-methylenetetrahydrofolate reductase (EC 1.1.1.68); (b) spontaneous release of [14C]formaldehyde from N5, N10-[14C]methylenetetrahydrofolate; and (c) nonenzymatic condensation of [14C]formaldehyde with tryptamine to form a radioactive carboline derivative. The occurrence of this sequence in leukocytes is suggested by data that show that the enzyme reaction is strongly stimulated by addition of flavin adenine dinucleotide and that the final product is chromatographically identical to the adduct formed in the reaction of [14C]formaldehyde with tryptamine. In the absence of tryptamine, a product accumulates that can react with other HCHO acceptors, i.e., beta-phenylethylamine and dimedone; another reaction product is tetrahydrofolate. Production of formaldehyde is relatively more active in normal lymphocytes than in normal granulocytes, but it is even higher in lymphocytes of chronic lymphocytic leukemia. Activity in granulocytes from a subject with chronic myelocytic leukemia is also elevated but to a lesser extent than activity in lymphocytes of chronic lymphocytic leukemia. Activity in granulocytes from a subject with chronic myelocytic leukemia is also elevated but to a lesser extent than activity in lymphocytes of chronic lymphocytic leukemia. Formaldehyde production in leukocytes is only slightly stimulated by addition of various cobalamins, and activity is normal in leukocytes from a vitamin B12-deficient patient. We conclude that the system is cobalamin independent. Thus, there exists an active pathway from N5-methyltetrahydrofolate to tetrahydrofolate other than the one catalyzed by cobalamin-dependent N5-methyltetrahydrofolate-homocysteine methyltransferase.
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PMID:Production of formaldehyde from N5-methyltetrahydrofolate by normal and leukemic leukocytes. 1 82

A patient with subacute eosinophilic leukemia is presented, with full recognition of the controversy surrounding that entity. Serum vitamin B12 and B12-binding protein studies and simultaneous complete blood counts were done before and during 6 months of high-dose, intermittent combination chemotherapy. The patient presented with extremely high levels of serum vitamin B12, unsaturated B12-binding capacity, and transcobalamin I, all of which resembled the highest values seen in chronic myelogenous leukemia. Serial studies, during and after remission induction, showed a precipitous fall of serum vitamin B12 and unsaturated B12-binding capacity to normal levels. The data show that transcobalamin I levels, which eventually reached low-normal range, correlate best with the level of circulating and bone marrow eosinophils. Transcobalamin II and serum third binder appeared to be normal throughout the patient's course. The B12-binding protein abnormalities are not considered diagnostic of eosinophilic leukemia.
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PMID:Serum vitamin B12-binding proteins in a case of eosinophilic leukemia. 6 Jun 95

Histocompatibility antigen (HLA) phenotypes of 34 patients with Ph1+ chronic myelogenous leukemia (CML) were evaluated for association with HLA antigens. Two control populations were compared to the CML patients: 142 normal volunteer platelet donors, and 160 normal donors of granulocyte transfusions. HLA typing was done by lymphocyte microcytotoxicity tests for nine antigens on sublocus A and 15 antigens on sublocus B. HLA-B7 and HLA-B12 were decreased in CML patients compared to both platelet and granulocyte donors. There was increased frequency of HLA-A3 in patients (41%) as compared to controls (25% and 33%); HLA-B5 - patients = 20%; controls 8% and 6%; and HLA-BW17 - patients = 17%; controls = 6% and 3% (P = 0.01). Median survival was 24+ months and independent of HLA. HLA-B5 and HLA-BW17 were significantly increased in patients with CML compared to two normal control populations. No increase in HLA-B8 was seen. Decreased frequency of HLA-B7 and B12 was noted. The significance of these differences is being evaluated.
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PMID:Frequency of HLA antigens in chronic myelocytic leukemia. 6 21

A 47-year-old white male developed massive hepatosplenomegaly, a pleural effusion, leucocytosis, and a left parasternal mass following a relatively symptom-free persistent hypereosinophilia for about 5 years. Bone marrow aspiration and biopsy and peripheral blood differential showed eosinophilia and a shift to the left with immature cells. A high serum B12 vitamin level and low LAP activity were found. Biopsy of the soft tissue mass revealed a granulocytic sarcoma (chloroma) with a hyperdiploid karyotype (49,XY, + 10, + 15, + 19,3q-), whereas the bone marrow cells had a normal male karyotype. The patient responded temporarily to chemotherapy but eventually developed CNS leukemia and went on to terminate in a frank blastic phase. This case illustrates hypereosinophilia and a myeloproliferative syndrome characterized by a somewhat indolent chronic course evolving into "eosinophilic leukemia" and granulocytic sarcoma, CNS involvement by leukemic cells and, finally, blastic transformation. It is possible that this case represents a variant of Ph1-negative CML to which the term "chronic eosinophilic leukemia" could be justifiably applied.
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PMID:Chromosomes and causation of human cancer and leukemia. XXXIV. A case of "hypereosinophilic syndrome" with unusual cytogenetic findings in a chloroma, terminating in blastic transformation and CNS leukemia. 29 66

Because of recent developments in the study of vitamin B12-binding proteins, the levels of the three serum binders were compared in serum and plasma samples from subjects with various disorders. The results allow the following conclusions: (1) As previously reported, transcobalamin (TC) III and to a lesser extent TC I are artifactually elevated in serum. The appear to be released in vitro during the clotting process, presumably from granulocytes. (2) Blood cells of patients with polycythemia vera release exceedingly large amounts of TC I and TC III in vitro. (3) The above findings support, but do not prove, at least a partial granulocytic source of TC I. Nevertheless, factors other than granulocytes influence TC I levels, as disorders characterized by increased TC I (most prominently chronic myelogenous leukemia but also several cases of cancer) manifest relatively little cellular release of TC I in vitro. (4) Despite the serum artifact, the serum abnormalities described in various conditions were seen in plasma also, even though the actual values of themselves were lower in plasma. The chief exception was TC III, which was elevated in plasma only in polycythemia vera (and in a few cases of leukocytosis). (5) EDTA-NaF anticoagulant is not suitable, as it causes plasma dilution, thus explaining previous reports of TC II level differences between serum and plasma. EDTA is therefore a preferable anticoagulant for vitamin B12-binding protein studies, although it too may not be ideal.
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PMID:Vitamin B12-binding proteins in serum and plasma in various disorders. Effect of anticoagulants. 41 9

Serum vitamin B12 and vitamin B12 binding proteins (transcobalamins, TCS) were determined in patients with malaria, amoebic liver abscess, carcinoma of the liver, infectious hepatitis, cirrhosis and chronic myelocytic leukemia (CML) as well as in 60 blood donor subjects. Serum vitamin B12 in patients with infectious hepatitis, cirrhosis and CML were higher than that of the normal subjects. The values of unsaturated vitamin B12 binding capacity (UBBC) in patients with carcinoma of the liver, infectious hepatitis, cirrhosis were lower while that of patients with CML were higher than that of the normal subjects. A markedly increased TCI and decreased TCII was observed in patients with CML while these changes was much less in patients with other liver diseases. The difference was possibly due to a flooding of vitamin B12 from damaged liver cells into the circulation and the decreased synthesis of transcobalamins in patients with liver diseases while the increased granulocytes, the source of TCI, was much increased in patients with CML.
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PMID:Vitamin B12 and vitamin B12 binding proteins in liver diseases. 60 23

Epidural myeloblastoma, which compressed the spinal cord, was the first evidence for chronic granulocytic leukemia, eosinophilic type, Ph chromosome negative. This manifestation was preceded by 3 years follow-up of a patient with persistent eosinophilia of 60% mature eosinophils. The only clues for the diagnosis of leukemia were splenomegaly and high serum vitamin B12, most of which was bound to transcobalamin I. The latter finding presents a useful diagnostic criterium in myeloproliferative disorders.
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PMID:Chronic eosinophilic leukemia complicated by epidural myeloblastoma. 80 41

1. Low serum B12 levels can be measured with considerable precision by microbiological assay with the Euglena gracilis assay and B12 deficiency can be recognised with a high level of consistency by either the Euglena or L. leichmannii assays. Either method is ideally suited for the assay of large numbers of specimens. The Lactobacillus leichmanii technique requires preliminary extraction of protein and it has been suggested that this may be a source of inaccuracy. 2. The radioisotope dilution assay should be the ideal method of measuring B12 levels in small or moderate numbers of specimens for it is a simple method that can be carried out in any laboratory with suitable counting equipment. After many false starts the conditions required for accurate assay are now understood. Each of 40 to 50 radioisotopic dilution techniques that have been introduced claims to be capable of differentiating B12 deficiency from control subjects but the reported correlations between the actual levels found in the two different assays are variable and the levels may be much higher with some radioisotopic methods. 3. The subnormal serum levels which are found in pernicious anaemia with all these techniques indicate severe reduction of the liver B12 level. A low serum B12 level in other conditions has, in the absence of associated folate or iron deficiency, the same significance. If the fall in the serum B12 level is associated with folate or iron deficiency, the tissue B12 levels are usually reduced but not to the low levels found in B12 deficiency states. 4. In practice, a subnormal B12 level is a valuable pointer not only to unsuspected pernicious anaemia but also to other gastrointestinal or nutritional disorders. The significance of a fall in the B12 level can only be understood if its cause is defined by a full clinical and gastroenterological investigation. 5. Falsely low serum B12 levels are found under certain iatrogenic conditions and B12 levels may be normal in spite of cellular deficiency of B12 under the rare circumstances of pernicious anaemia being associated with chronic myeloid leukaemia or when there is deficiency of TC 2.
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PMID:The serum vitamin B12 level: its assay and significance. 82 83

Elevation of transcobalamin I and serum vitamin B12 levels has usually been associated with increased granulocytic proliferation, such as occurs in chronic myelogenous leukemia. Two patients with metastatic cancer had extremely high serum vitamin B12 and transcobalamin I levels--greater than those seen in even the most intense granulocytic proliferation--that were not explainable by leukocytosis. The subjects' serum vitamin B12 levels were 18,750 and 21,221 pg per milliliter (normal, 471 plus or minus 174 pg per milliliter, mean plus or minus S.D.) and unsaturated vitamin B12 binding capacity 158,750 and 5,400 pg per milliliter (normal, 1153 plus or minus 313 pg per milliliter) respectively. The abnormally elevated serum binder was shown to be identical with transcobalamin balamin I in every respect. Levels of transcobalamin II and serum third binder were normal. The cause of the binder abnormality is unknown, but factors other than granulocyte proliferation may control or contribute to the production or accumulation of transcobalamin I.
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PMID:Extreme elevation of serum transcobalamin I in patients with metastatic cancer. 105 6

The technique described in the preceding paper was applied to 12 abnormal sera selected for their increase in one or more B12-binding proteins. Even in the presence of large amounts of R-type binder, the ammonium sulfate technique gave a reliable separation of R binding proteins from TC II. Measurement of the TC II in abnormal sera gave results identical to those obtained by the more standard gel filtration. The R binders of four subjects with myeloproliferative disease were further separated into alpha2-R and alpha1-R. The pattern of B12 binding of polycythemia vera (PV) was an exaggeration of the normal pattern. Binding to alpha2-R was three to four times that to alpha1-R, although the total amounts bound to both were increased. In chronic myelogenous leukemia (CML), both alpha2-R and alpha1-R were also increased, but in contrast to binding in normal sera, alpha1-R predominated. In order to interpret the findings, either whole serum R or alpha1-R and alpha2-R from patients with myeloproliferative disease were subject to isoelectric focusing. Alpha2-R consisted pricipally of components isoelectric at pH 2.9, 3.0, and 3.1. These components were present in only minor amounts in normal serum and were somewhat increased in the serum of PV. These components were very much increased in the serum of CML and predominated. Alpha2-R consisted of those components isoelectric at pH 3.4,3.6, and 4.0. These components predominated in the unsaturated binding capacity of normal sera and that of PV. It was concluded that the division of plasma R binders into alpha1-R and alpha1-R by the technique described provided information useful in the study of myeloproliferative diseases.
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PMID:Measurement of vitamin B12-binding proteins of plasma. II. Interpretation of patterns in disease. 105 10


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