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)

A leukaemia presenting with two morphologically different blast populations failed to respond to either antimyeloid or antilymphoid treatment and showed a rapid clinical progression. Immunophenotyping provided good evidence for two blast populations, one lymphoid and the other lymphoid with granulocyte monocytic markers. Two different gene rearrangements within JH were also observed with band densities corresponding to the sizes of the two blast cell populations. A t(19; 22) translocation was observed in almost all cells at presentation one of which evolved into a subclone, becoming dominant in the terminal phase of the disease. We show here both the clonal evolution and clonal competition that occurred in this leukaemia and suggest that the potential of the tumour stem line for rapidly producing diversity was the reason for the resistance to treatment.
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PMID:Rapid production of diversity during the progression of a mixed lineage leukaemia. 140 14

Aspergillus quadrilineatus was found to be the etiologic agent of pansinusitis in a patient suffering from acute nonlymphoblastic leukemia and who had undergone allogeneic bone marrow transplantation. A. quadrilineatus was cultured from biopsy specimens of the maxillary sinus, and tissue sections with fungal stains showed a necrotic area containing dichotomously branching septate hyphae, which is morphologically consistent with Aspergillus species. The patient was successfully treated with a combination of surgical debridement, granulocyte transfusions, and intravenous administration of amphotericin B-cholesterol sulfate colloidal dispersion. This is the first report of an infection caused by A. quadrilineatus.
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PMID:Aspergillus quadrilineatus, a new causative agent of fungal sinusitis. 145 21

Determining both myeloid and lymphoid chimerism after T-cell-depleted allogeneic bone marrow transplantation (BMT) could be helpful in the understanding of the biology of engraftment and could provide a rational method of assessing the ability of different conditioning regimens to promote engraftment. We prospectively investigated the role of different pretransplant conditioning regimens in 29 leukemic patients post-BMT by assessing myeloid and T-cell chimerism using a rapid and sensitive polymerase chain reaction (PCR) method. Minisatellites are hypervariable regions of DNA consisting of tandem repeats of a core nucleotide sequence, and allelic polymorphism results from differences in the number of the repeats. We used this variation to distinguish between donor and recipient cells post-BMT. Seventeen patients (9 sibling and 8 unrelated donors) received conditioning with hyperfractionated total body irradiation (TBI), thiotepa, and cyclophosphamide (Cy). Of the other 12 patients (all sibling donors), 11 received TBI plus Cy plus another agent: VP16, carboplatinum, or AZQ. One patient received TBI plus thiotepa plus VP16. All but one of the patients studied received marrow from HLA-identical donors. PCR analysis confirmed donor lymphoid engraftment within 8 days of transplant in six of six patients studied. All granulocyte DNA was of donor origin within the first 4 weeks of transplant, regardless of the conditioning regimen. The day +28 T cells were exclusively of donor origin in 14 of 17 patients who received TBI plus thiotepa plus Cy, but were mixed chimeric in 10 of 12 patients who received other conditioning regimens (P < .001). Early graft rejection was seen in one unrelated transplant recipient conditioned with TBI plus thiotepa plus Cy. Late graft failure was observed in 3 of 12 patients with mixed T-cell chimerism and in none of 16 patients with full donor chimerism at day +28. However, 5 of 16 patients who had complete T-cell chimerism at day +28 developed acute graft-versus-host disease (GVHD), whereas no patient with mixed chimerism had acute GVHD. Our results indicate that minisatellite PCR is a rapid and sensitive method for assessing chimerism post-BMT, that the donor T cells are important for consistent durable engraftment, and that TBI plus thiotepa plus Cy may be superior to the other regimens studied in inducing full donor chimerism. Larger numbers and longer follow-up are necessary to confirm these data and also to assess the relationship between complete donor T-cell chimerism and leukemia-free survival.
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PMID:Myeloid and lymphoid chimerism after T-cell-depleted bone marrow transplantation: evaluation of conditioning regimens using the polymerase chain reaction to amplify human minisatellite regions of genomic DNA. 146 26

Human IL-9 is a T cell-derived lymphokine that is abundantly expressed upon activation with mitogens. The observation that IL-9 induction peaks as late as 28 h after stimulation suggested the involvement of secondary signals in this process. The finding reported here that IL-9 expression is blocked by cycloheximide strongly supports this hypothesis. Moreover, we identify IL-2 as the critical element controlling IL-9 expression in T cells. We show (i) that anti-IL-2R antibodies block IL-9 expression in T cells stimulated with PMA and anti-CD3 and (ii) that IL-2, of a panel of cytokines, is the only molecule that synergizes with PMA for IL-9 induction. The latter finding is confirmed in a T cell leukemia line. Finally, we demonstrate that IL-2 plays a regulatory role in the induction of other cytokines, such as IL-4, IL-5, IL-6, and granulocyte/macrophage-CSF, in fresh peripheral T cells.
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PMID:IL-2 dependence of IL-9 expression in human T lymphocytes. 153 52

We have previously described differentiation associated tyrosine protein kinase activity in WEHI-3B monomyelocytic leukemia cells and have presented evidence which suggests that this activity may not be involved in the initiation of the differentiation process, but more likely has a functional role in the mature myeloid cell. The present study was undertaken in an attempt to identify the protein(s) responsible for the tyrosine protein kinase activity and to seek a potential role for this activity in the mature cell. We and others have detected the p92c-fes tyrosine protein kinase in WEHI-3B cells. This protein has been implicated in myeloid differentiation, as well as in the transduction of signals in response to granulocyte macrophage colony stimulating factor (GM-CSF). Thus, it was of interest to determine whether tyrosine phosphorylation may be involved in the response of WEHI-3B cells to GM-CSF. Treatment of differentiated WEHI-3B D+ cells with GM-CSF was found to result in the tyrosine phosphorylation of a number of endogenous cellular proteins in a concentration-dependent, rapid and transient manner. In contrast, the cytokine did not elicit such a response in undifferentiated cells, despite the fact that undifferentiated cells have been reported to possess GM-CSF receptors. These findings are consistent with the concept that the effects of GM-CSF on differentiated myeloid cells are mediated through tyrosine phosphorylation, that only differentiated cells are competent to accomplish this event, and that this response constitutes at least one functional role for the myeloid differentiation associated tyrosine protein kinase activity.
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PMID:Differentiation stage specificity of tyrosine phosphorylation in response to granulocyte macrophage colony stimulating factor (GM-CSF). 155 4

The Philadelphia (Ph1) chromosome is a specific structural abnormality in which the abl oncogene is activated due to the formation of the novel chimeric gene, bcr/abl. To investigate the clinicopathological role of bcr/abl in Ph1-positive chronic myelogenous leukaemia (CML), we studied the clonal origin of haematopoietic progenitors by detecting bcr/abl mRNA in a single haematopoietic colony using the polymerase chain reaction (PCR). Nine patients with CML were examined. In 5 chronic phase patients, all granulocyte/macrophage (CFU-GM) and erythroid (BFU-E) progenitor-derived colonies were positive for bcr/abl mRNA. Colonies in which the transcripts were not detectable were observed in 4 patients. These 4 patients included one patient with a normal karyotype and without splenomegaly, a patient with cyclic oscillation of her white blood cell level, a patient treated with busulfan and interferon-alpha (INF-alpha), and a patient relapsing after allogenic bone marrow transplantation (BMT). Our observations indicate that detection of Ph1-positive clones by PCR may be used to evaluate clinical stages and the effects of treatment in CML.
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PMID:Analysis of clonality at the level of progenitors in chronic myelogenous leukaemia using the polymerase chain reaction. 156 40

This study aimed to evaluate the effect of melphalan on both terminal divisions and self-renewal capacity of acute myeloblastic leukemia (AML) progenitors (colony-forming units, CFU-L) grown in methylcellulose. Terminal divisions and self-renewal were assayed by primary (PE1) and secondary (PE2) colony formation, respectively. Thirteen cases of AML, were tested. Melphalan induced a negative exponential dose-effect on CFU-L survival. Moreover, melphalan was equally effective in inhibiting CFU-L growth in both PE1 and PE2 assays, with D10 values of 1.53 +/- 0.17 micrograms/ml and 1.59 +/- 0.21 micrograms/ml for PE1 and PE2, respectively (p = 0.48). Cytotoxicity of melphalan on CFU-L did not differ significantly from that observed for normal hemopoietic granulocyte-macrophage colony-forming units, erythroid burst-forming units, and granulocyte-erythroid-macrophage-megakaryocyte progenitors. Mafosfamide-lysine, a stable cyclophosphamide congener, strongly inhibited primary colony formation (PE1) with a D10 value of 14.46 +/- 1.76 micrograms/ml, but was much less efficient in the PE2 assay. Our findings suggest that the self-renewal capacity of AML progenitors can be differentially affected by alkylating agents. Moreover, since it is now considered that chemotherapy should be preferentially directed against the self-renewal of leukemic progenitors, melphalan might offer a greater potential than cyclophosphamide or cyclophosphamide derivatives in the therapy of AML.
Leukemia 1992 Mar
PMID:Effect of melphalan against self-renewal capacity of leukemic progenitors in acute myeloblastic leukemia. 156 57

The availability of an in vitro assay able to detect hematopoietic progenitor cells closely related to those responsible for marrow engraftment following autologous bone marrow transplantation (ABMT) prompted us to establish a procedure aimed at maximally increasing the concentration of the cyclophosphamide derivative mafosfamide used for marrow purging. It, therefore, was the aim of the present study to investigate in a group of patients with acute nonlymphoblastic leukemia (ANLL; n = 19) and acute lymphoblastic leukemia (ALL; n = 19) in complete remission the effect of mafosfamide at the level of adherent blast colony-forming units (blast colony-forming units, CFU-Blast), as well as multipotential (granulocyte erythrocyte macrophage megakaryocyte colony-forming units, CFU-GEMM), erythroid (erythroid burst-forming units, BFU-E), and granulocyte-macrophage (granulocyte-macrophage colony-forming units, CFU-GM) progenitor cells. When nonadherent marrow mononuclear cells (MNCs) were incubated (30 min, 37 degrees C) with increasing doses of mafosfamide (30-120 micrograms/ml), a statistically significant (p less than or equal to 0.0005) dose-dependent suppression of CFU-Blast growth was observed. The mean (+/- 1 standard error of the mean [SEM]) values of 50% inhibition (ID50) of the CFU-Blast growth were not significantly different for ANLL (106 +/- 5) and ALL (107 +/- 5) patients. Analysis of CFU-Blast ID50 distribution demonstrated that ID50 ranged from 100 to 120 micrograms/ml in 17 cases (45%), whereas it ranged from 60 to 100 micrograms/ml in 12 cases and from 120 to 160 micrograms/ml in 9 cases. A statistically significant (p less than or equal to 0.05), dose-dependent suppression of colony growth from multi-potential and lineage-restricted progenitor cells was also observed. However, the value of CFU-Blast ID50 was significantly higher (p less than or equal to 0.05) than CFU-GEMM, BFU-E, and CFU-GM ID50 and ID95 values. In conclusion, our data demonstrate that: 1) the CFU-Blast assay allows to detect on an individual basis the doses of mafosfamide used for marrow purging, and 2) the concentrations of mafosfamide extrapolated by using the CFU-Blast assay are significantly higher than those obtained with the CFU-GM assay. The absence of any detrimental effect on marrow engraftment in vivo supports the safety of the CFU-Blast assay to evaluate the dose of mafosfamide used for marrow purging before ABMT.
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PMID:Differential sensitivity of adherent CFU-blast, CFU-mix, BFU-E, and CFU-GM to mafosfamide: implications for adjusted dose purging in autologous bone marrow transplantation. 156 48

The v-myb oncogene of the acute avian leukemia virus E26 encodes a transcription factor that directly regulates the promyelocyte-specific mim-1 gene (Ness, S.A., Marknell, A. and Graf, T. Cell, 59, 1115-1125). We have investigated the relationship between the c-myb proto-oncogene and the transcription of the mim-1 gene both in vitro and in vivo. We demonstrate that the c-myb protein can transactivate the transcription of mim-1 in a transient transfection assay. In the chick embryo, we confirm that mim-1 is specifically expressed during granulopoiesis and we show that the expression of c-myb and mim-1 are perfectly correlated in the granulocytic spleen and pancreas. However we suggest that mim-1 is efficiently transcribed in the absence of c-myb in the yolk sac and in the promyelocytes at the onset of the colonization of the bursa of Fabricius. On the other hand c-myb transcripts detected in the early hemopoietic progenitor cells, in lymphoid cells and in proliferative epithelia are never associated with mim-1 transcription. We conclude that the granulocyte-specific mim-1 gene is regulated by c-myb-dependent and c-myb-independent mechanisms depending upon the environment in which granulocytic precursor cells differentiate.
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PMID:Expression patterns of c-myb and of v-myb induced myeloid-1 (mim-1) gene during the development of the chick embryo. 157 54

We have recently established ME-1, a human myelomonocytic leukaemia cell line derived from acute myelomonocytic leukaemia with eosinophilia (M4E0). When ME-1 cells were cultured in serum-free medium, they stopped proliferating and began to differentiate morphologically, functionally and phenotypically to mature granulocyte-like cells. The protein kinase inhibitor, 1-(5-isoquinolinyl-sulphonyl)-2-methylpiperazine (H-7) enhanced this differentiation dose-dependently. Upon addition of fetal calf serum (FCS) to the serum-free medium, the differentiation of ME-1 cells into granulocyte-like cells was inhibited and they resumed cell growth. We have recently reported that the differentiation of ME-1 cells into macrophage-like cells induced by IL-3 and GM-CSF involved the activation of protein kinase C. The present results indicate that ME-1 is a bipotential cell line that can differentiate into granulocyte-like cells or macrophage-like cells, and that protein kinase C is closely related to each form of differentiation.
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PMID:Granulocytic differentiation of the human myelomonocytic leukaemia cell line ME-1 in serum-free culture. 158 Dec 9


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