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A Deisseroth

Publications and source records attributed to A Deisseroth.

At least 55 records · Page 3Linked to original sources

Polyclonal hematopoiesis in interferon-induced cytogenetic remissions of chronic myelogenous leukemia.

Interferon (IFN) therapy of early chronic myelogenous leukemia (CML) frequently produces partial or complete cytogenetic remission of the disease. Patients with complete cytogenetic remission often continue on therapy for several years with bone marrow showing only diploid (normal) metaphases. We studied hematopoiesis in five female patients with major cytogenetic remissions from CML during IFN therapy. Clonality analysis using the BstXI PGK gene polymorphism showed that granulocytes were nonclonal in all patients during cytogenetic remission. BCR region studies showed rearrangement only in the one patient whose remission was incomplete at the time of sampling. Granulopoiesis is nonclonal in IFN-induced remissions of CML and may be derived from normal hematopoietic stem cells.

Clone Cells↗

Identification of a complex formed between nuclear proteins and the transcriptional enhancer of interferon-inducible genes that is present in the peripheral blood myeloid cells of CML but not normal individuals.

Interferon-alpha (INF-alpha) induces cytogenetic remissions in 20% of chronic myelogenous leukemia (CML) patients. To clarify the mechanisms through which this antiproliferative action of IFN is mediated in the CML cell, a modification of the mobility-shift assay was used to follow the formation of complexes between nuclear proteins and IFN-inducible transcriptional enhancers involved in mediating the cellular effects of IFN-alpha. These studies identified a complex that was present in the myeloid cells of 18/24 (75%) of chronic-phase CML patients tested whose cells contained 100% Philadelphia chromosome positive (Ph+) cells, while the proteins of none of the samples tested from normal peripheral blood samples and only 22% (2/9) of the CML patients in an IFN-induced major cytogenetic remission (less than 30% Ph+ cells) contained these complexes. These studies suggest that the mobility-shift assay detects changes in the CML myeloid cell that distinguish it from the normal myeloid cell.

Base Sequence↗

Detection of minimal residual disease by polymerase chain reaction of bcr/abl transcripts in chronic myelogenous leukaemia following allogeneic bone marrow transplantation.

The prognostic significance of detecting minimal residual disease by polymerase chain reaction (PCR) amplification of bcr/abl mRNA transcripts was investigated in 27 bone marrow samples from 20 patients with Philadelphia chromosome (Ph1) positive chronic myelogenous leukaemia (CML) in complete cytogenetic remission following allogeneic bone marrow transplantation. Sixteen were transplanted in first chronic phase, two were in second chronic phase, one was in accelerated phase and one was in blast crisis. All 20 achieved complete cytogenetic remission post transplant and 15 patients had detectable bcr/abl mRNA by PCR from 2 to 22 months following the procedure. One of these patients had graft failure and one died from graft-versus-host-disease at 7 months. Of the remaining 13 PCR-positive patients, only one (8%) relapsed after 23 months; the other 12 were alive and still in remission after a median follow-up of 16+ months (ranging 5+ to 29+ months). Five patients were PCR negative; all are alive in complete clinical and cytogenetic remission at 10+, 11+, 19+, 25+ and 25+ months post transplant. In this study, detection of subclinical Ph1-positive cells by PCR was not associated with imminent clinical or cytogenetic relapse. Since late recurrence may potentially occur, long-term follow-up is required to definitely determine the prognostic value of the PCR assay.

Adult↗

Treatment of chronic myelogenous leukemia in accelerated and blastic phases with daunorubicin, high-dose cytarabine, and granulocyte-macrophage colony-stimulating factor.

PURPOSE: The study was undertaken to improve the results of intensive chemotherapy in chronic myelogenous leukemia (CML) in accelerated (CML-AP) and blastic phases (CML-BP) by the addition of granulocyte-macrophage colony-stimulating factor (GM-CSF) as supportive therapy. PATIENTS AND METHODS: Forty-eight patients were treated with daunorubicin 120 mg/m2 intravenously on day 1, cytarabine (ara-C) 1.5 g/m2/d by continuous infusion over 24 hours for 4 days, and Solu-Medrol (methylprednisolone; The Upjohn Co, Kalamazoo, MI) 100 mg/d for 5 days, followed on day 5 by GM-CSF 125 micrograms/m2/d over 6 hours until recovery of granulocyte count above 2.0 x 10(3)/microliters. Twenty-four patients had CML-BP, and 24 had CML-AP. RESULTS: During remission induction, 45 patients (94%) developed febrile episodes (fever of unknown origin, 23 patients [48%]; documented infections, 22 patients [46%]). The median time to recovery of granulocyte count above 0.5 x 10(3)/microliters was 29 days and to platelet count above 30 x 10(3)/microliters, 28 days. Overall, 14 of 48 patients (29%) achieved a complete hematologic remission (CHR), and seven (15%) reverted to a second chronic phase. CHR was noted in eight of 24 patients with CML-BP (33%), and in six of 24 patients with CML-AP (25%). Cytogenetic responses were observed in 11 patients (23%), but were transient. Sixteen patients developed either fluid retention, hypotension, pleuropericardial effusions, or pericarditis, or a combination of these side effects. These side effects were severe in four patients and are likely to be disease-associated, as a similar regimen of intensive chemotherapy and GM-CSF at the same dose and schedule in acute lymphocytic leukemia was not associated with these side effects. CONCLUSIONS: The results pertinent to remission rates, induction mortality, myelosuppression profile and related complications, and overall survival were not significantly improved compared with previous experience. In summary, the results of intensive chemotherapy in CML-transformed phases remain poor, despite the addition of GM-CSF as a supportive measure.

Adult↗

Altered conformation of the p53 protein in myeloid leukemia cells and mitogen-stimulated normal blood cells.

Expression of the normal p53 gene promotes cell differentiation, maturation and apoptosis. The mutant p53 gene, which does not function normally, is frequently expressed at elevated levels in tumor cells [for review see Lane, D.P. & Benchimol, S. (1990). Genes Dev., 4, 1-8]. We have analysed the expression of and mutational change in the p53 gene in the peripheral blood cells of 49 primary acute myeloid leukemia (AML) patients. The p53 protein levels were elevated in 37 patients (75%) when measured by immunoprecipitation with antibodies PAb1801 and PAb421, which recognize both normal and mutant forms of the protein. The p53 protein from 32 of these 37 patients was immunoprecipitated by PAb240, which recognizes a conformation of p53 protein associated with point mutations. However, point mutations were detected by single-stranded conformation polymorphism (SSCP) assay and direct sequencing in only three patients at codons 178, 245, 273 and 290. Growth stimulation of normal lymphocytes also generated p53 which was immunoprecipitable by PAb240. Thus, alteration of p53 conformation, rather than acquisition of point mutations, could be the mechanism underlying the increased proliferation of myeloid cells in most AML patients.

Acute Disease↗

Rearrangement and expression of p53 in the chronic phase and blast crisis of chronic myelogenous leukemia.

We tested a population of over 60 patients with chronic myelogenous leukemia (CML) for changes in the structure and expression of the p53 gene, which is located on chromosome 17. Six of 27 (22%) blast crisis samples and 3 of 5 (60%) accelerated phase samples had rearrangements of chromosome 17, whereas only 3 of 42 (7%) chronic phase patients had cytogenetic changes in chromosome 17. There was no loss of heterozygosity during the transition to blastic crisis among seven individuals who were informative for polymorphic probes for regions in or around the p53 gene on 17p. One patient in the chronic phase and one patient in the blastic phase of the 61 CML patients studied exhibited rearrangements of the p53 gene that were detectable by Southern analysis. One p53 allele was rearranged in the chronic phase patient and both p53 alleles were rearranged in the blastic phase patient. The p53 messenger RNA (mRNA) was of normal size (2.8 kb) in chronic phase and blast crisis, and the expression of the p53 gene was at least as high or higher in blast crisis as in the chronic phase of CML. The high incidence of abnormalities of chromosome 17 in blast-crisis CML found in our studies and the discovery of rearrangements of the p53 gene in two CML patients studied suggest that further study with probes for the p53 gene and anonymous polymorphic sites in chromosome 17 should be conducted in CML.

Blast Crisis↗

Use of recombinant human hematopoietic growth factors and autologous bone marrow transplantation to attenuate the neutropenic trough of high-dose therapy.

This manuscript summarizes our experience with recombinant human granulocyte colony-stimulating factor (rhG-CSF) with high-dose Cytoxan, carmustine and etoposide (CBV in Hodgkin's disease). rhG-CSF regularly shortened the neutropenic phase following autologous bone marrow transplantation. However, this effect was more marked on the latter part of neutrophil recovery than the early part of granulocyte recovery to 100 granulocytes/microliters. The frequency of afebrile episodes was not reduced by rhG-CSF administration, but there was a tendency for the duration of fever to be shortened. Increasing doses and continuous infusion did not hasten the early part of neutrophil recovery needed to prevent the onset of infection, but was more effective than bolus infusion in increasing the rate of late neutrophil recovery. If fevers are to be prevented in this patient population, the duration of an absolute granulocyte count of less than 100/microliters will have to last only a few days. Recombinant hematopoietic growth factors alone do not hasten recovery fast enough to prevent the onset of afebrile episodes. Studies are described using both recombinant growth factor and peripheral blood and bone marrow cells to see if the neutropenic trough can be further shortened over that achievable with growth factor and autologous transplant alone.

Agranulocytosis↗

Treatment of poor-prognosis, newly diagnosed acute myelogenous leukemia with high-dose cytosine arabinoside (Ara-C) and rHUGM-CSF.

We gave 4 days of high-dose Ara-C followed 2 days later by rHUGM-CSF (which continued until the neutrophil count was greater than 1000/microliters) to 12 patients with newly diagnosed AML and a relatively poor prognosis. Six CRs occurred, there were four deaths during induction, and in only one case was there an rHUGM-CSF-associated growth of leukemia. The pattern of hematologic recovery was variable but in some patients rHUGM-CSF seemed to accelerate normal myelopoiesis following chemotherapy. Continued investigation of rHUGM-CSF and chemotherapy in AML is warranted.

Aged↗

A phosphatase activity present in peripheral blood myeloid cells of chronic myelogenous leukemia patients but not normal individuals alters nuclear protein binding to transcriptional enhancers of interferon-inducible genes.

Cytoplasmic protein from peripheral blood myeloid cells of chronic myelogenous leukemia (CML) patients altered the electrophoretic mobility of complexes formed between nuclear proteins and interferon-inducible transcriptional enhancers. Immature myeloid marrow cells (blasts and promyelocytes) have a higher level of this activity than do mature myeloid marrow cells (bands and polys). This activity, which is not detectable in the peripheral blood cells of normal individuals, is at least 50-fold higher in CML marrow blasts and promyelocytes than that found in marrow blasts and promyelocytes of normal individuals. This activity was inhibited by in vivo incubation of immature myeloid cells with the phosphatase inhibitor, sodium orthovanadate (0.2 mM), and by adding orthovanadate (20 mM) directly to cytoplasmic proteins of myeloid cells. Interferon-alpha (1,000 U/ml) reduced the effects of the CML myeloid cell cytoplasmic protein on the electrophoretic mobility of nuclear protein-DNA complexes. These data suggest that a unique phosphatase may be involved in the abnormalities in CML which are modulated by interferon-alpha.

Acid Phosphatase↗

Early metabolic response to tumor necrosis factor in mouse sarcoma: a phosphorus-31 nuclear magnetic resonance study.

To investigate the effects of recombinant human tumor necrosis factor alpha (rHuTNF-alpha) on high-energy phosphate metabolism of cancer cells, 31P nuclear magnetic resonance (NMR) studies were performed on a murine methylcholanthrene-induced sarcoma. Injection of 15 micrograms of rHuTNF-alpha caused progressive depletion of ATP and phosphocreatine within 90 min, together with an increase in inorganic phosphate. Metabolic changes were correlated with the early histological appearance of thrombosis and hemorrhage. A spatially localized NMR technique demonstrated that these changes were specific for the tumor. Acute ischemia of the tumor produced similar metabolic changes; thus the metabolic effects of rHuTNF-alpha could be due to either a primary action on tumor biochemistry or a secondary action produced by ischemia. These findings indicate that rHuTNF-alpha has a very rapid onset of action, which can be detected by 31P NMR. Furthermore, the results suggest that 31P NMR spectroscopy will be extremely useful for detecting early biochemical changes produced by rHuTNF-alpha or other treatments in animal and human cancers.

Adenosine Triphosphate↗

Regulation of adult and embryonic genes in human leukemia cells.

In this article, we have reviewed studies showing that altered expression of regulatory genes results in activation of embryonic genes in human leukemia cells. These data have led to important new insights as to how mutations in regulatory genes can lead to disease states in man.

Cell Differentiation↗

S1 nuclease analysis of alpha-globin gene expression in preleukemic patients with acquired hemoglobin H disease after transfer to mouse erythroleukemia cells.

The loss of alpha-globin gene transcriptional activity rarely occurs as an acquired abnormality during the evolution of myeloproliferative disease or preleukemia. To test whether the mutation responsible for the loss of alpha-globin gene expression (hemoglobin H disease) in these patients is linked with the alpha-globin genes on chromosome 16, we transferred chromosome 16 from preleukemic patients with acquired hemoglobin H disease to mouse erythroleukemia cells and measured the transcriptional activity of the human alpha-globin genes. After transfer to mouse erythroleukemia cells, the expression of human alpha-globin genes from the peripheral blood or marrow cells of preleukemic patients with acquired hemoglobin H disease was similar to that of human alpha-globin genes transferred to mouse erythroleukemia cells from normal donors. These data showed that factor(s) in the mouse erythroleukemia cell can genetically complement the alpha-globin gene defect in these preleukemia patients with acquired hemoglobin H disease and suggest that altered expression of a gene in trans to the alpha-globin gene may be responsible for the acquisition of hemoglobin H disease in these patients.

Animals↗

Characterization of an unique RNA initiated immediately upstream from human alpha 1 globin gene in vivo and in vitro: polymerase II-dependence, tissue specificity, and subcellular location.

We have identified an abundant transcript initiated upstream from the canonical cap site of human alpha 1 globin gene in bone marrow cells and in COS-7 cells transfected with an alpha 1 globin gene-containing plasmid. Similar to the major alpha 1 globin transcript, this upstream RNA is present almost exclusively in the cytoplasm of the transfected COS-7 cells. It is also synthesized efficiently in vitro by RNA polymerase II in the nuclear extracts prepared from a Hela cell line and an erythroleukemia cell line, K562. RNAs isolated from these cell lines, however, do not contain this upstream transcript. The putative 5' end of the alpha 1 globin upstream RNA is mapped by primer extension to base -45, which is located in between the CCAAT and TATA boxes. The synthesis of this RNA in vitro and in vivo, and the close proximity of its 5' end to the promoter of the alpha 1 globin gene suggest a common mechanism regulating the transcriptional initiation of both the upstream and the major alpha 1 globin RNAs.

Animals↗