Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0598766 (leukemogenesis)
 4,065 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In vitro proliferative response of the blast cells from 21 AML patients to hematopoietic growth factors (IL-3, GM-CSF, G-CSF and MCSF) was investigated. Proliferation of AML cells in the majority of cases was induced or promoted by one or more CSFs, among which the stimulation of IL-3 was the most effective. Spontaneous proliferation of the blast cells was also observed in half of the cases and could be inhibited as well as promoted by some CSFs. It is suggested that in vitro proliferation of AML cells varies from patient to patient and that CSF plays important roles in leukemogenesis.
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PMID:[Effects of various recombinant human hematopoietic growth factors on proliferation of blast cells in acute myeloid leukemia in vitro]. 128 86

To investigate the possible role of the product of the retinoblastoma susceptibility gene, pRB, in leukemogenesis, we examined fresh leukemia cells from 56 cases of primary leukemia (AML, 32; ALL, 12; CML-BC, 9; CLL, 3) for expression of pRB by using an immunoblotting assay with anti-pRB monoclonal antibodies PMG 3-245 or 3-340. Expression of the 70 kDa heat shock protein (Hsp70) was examined simultaneously as an internal control. pRB was found to be absent or expressed at an abnormally low level in 13 of 56 cases. Abnormal expression of pRB was most common in AML (8/32) and CML-BC (4/9), and less common in ALL (1/12). Expression of pRB was not induced in two cases of pRB- AML cultured for 24 h with GM-CSF, indicating that pRB expression could not be induced by increasing the rate of proliferation. The eight cases of AML lacking pRB protein were examined for RB1 mRNA by Northern blot. Two lacked RB1 mRNA and six had a normal-sized mRNA (approximately 4.7 kb), although the amount of RB mRNA was very low in some cases. RB1 gene structure was normal by Southern blot in all eight cases lacking pRB protein which were studied. These results show that lack of pRB expression is relatively common in human myeloid leukemias, and suggests that loss of pRB expression could contribute to the altered growth control of these cells.
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PMID:Heterogeneous expression of the product of the retinoblastoma susceptibility gene in primary human leukemia cells. 188 10

DNA contents of c-FMS and GM-CSF genes were analyzed by densitometer in nine patients with myelodysplastic syndrome or acute myeloid leukemia associated with abnormality of chromosome 5. Five patients with deletion in the long arm of chromosome 5 had loss of both c-FMS and GM-CSF genes. These findings suggest that c-FMS oncogene and GM-CSF gene locating in the critical region on chromosome 5 seem to have an important role in the process of leukemogenesis.
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PMID:[Parallel loss of c-FMS and GM-CSF genes in myeloid leukemias with 5q-chromosome]. 194 39

Factor-independent mutants of hematopoietic cells, especially of multipotent cells, are valuable tools to identify genes that regulate stem cell proliferation and differentiation and thus may be important in leukemogenesis. Factor-independent mutants from both myeloid precursor and hematopoietic stem cell lines were isolated. The frequency of such mutants in a given cell population was one to two orders of magnitude lower for the multipotent cell line FDC-Pmix (3.6 x 10(-9)) than for the myeloid precursors, FDC-P1-M (1.7 x 10(-8)) and D35 (2.2 x 10(-7)). Analysis of these mutants revealed several mechanisms by which growth autonomy was obtained, either with or without direct contribution of growth factor gene activation. The molecular basis of spontaneous activation of the Multi-CSF (Interleukin3) gene was determined and compared to activation of the GM-CSF gene in a previous study. Multi-CSF gene activation in both precursor and stem cells was caused by the insertion of an intracisternal A particle (IAP) provirus. In two independent mutants of the D35 cell line, activation of the Multi-CSF or the GM-CSF gene was caused by almost identical IAPs with a 99% homology in the U3 and R region of the long terminal repeat. This result demonstrates that only one class of IAPs, or perhaps a single provirus, is involved in transposition and gene activation in a particular cell line. A unique example of anti-sense promotion from an IAP provirus in one Multi-CSF mutant underlines the versatility of these elements as natural insertional mutagens.
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PMID:Retrotransposons as mutagens in the induction of growth autonomy in hematopoietic cells. 217 39

Realising the therapeutic potential of colony-stimulating factors (CSFs) depends upon understanding the biological responses elicited by these regulators in target hemopoietic cells, and determining the biochemical nature of signals transduced through their receptors. These signals can lead to growth, differentiation or the activation of an effector function. CSF-dependent cells maintained in culture resemble pre-leukemic cells and releasing cells from a factor-dependent growth state must be a final step in leukemogenesis. The measurement of metabolic changes in cells following ligand-receptor interactions has thus far failed to reveal the biochemical identity of growth signal transducing events. The patterns of growth responses observed in various CSF-dependent cell lines provide some idea of the relationship of these events for different CSF species. A number of IL-3-dependent cell lines can be switched to an IL-2- or a GM-CSF-dependent growth state. This implies the intracellular pathways activated by signal transduction through their different receptors must be related. The expression of the v-src oncogene in IL-3- and GM-CSF-dependent cells leads to CSF-independent growth, whereas in an IL-2-dependent growth state the expression of v-src in these same cells does not lead to a loss of the requirement for IL-2 for growth. It might be argued that signal transduction through IL-3- or GM-CSF-specific receptors involves a protein tyrosine kinase. However, the addition of IL-3 or GM-CSF to cells expressing v-src results in a decrease in tyrosine kinase activity, suggesting that the effect of IL-3- or GM-CSF-specific signal transduction is to inhibit the expression of tyrosine kinase. It is unlikely that G-CSF signal transduction involves a receptor-associated tyrosine kinase. 32Dcl-23 cells respond to G-CSF by cell division and terminal differentiation, but when these cells are transformed to factor-independent growth following v-src infection, they remain responsive to G-CSF but lose the capacity to terminally differentiate. We have investigated the growth and differentiative responses of a range of human myeloid leukemias to G-CSF, IL-3 and GM-CSF. There is heterogeneity in the responses of different leukemic cells to these growth factors.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Effects of colony-stimulating factors on leukemia progenitor cells and oncogene expression. 307 33

Most primary myeloid leukemias are dependent for proliferative stimulation on the glycoprotein colony-stimulating factors. These agents are therefore mandatory co-factors in the development of myeloid leukemia. The CSFs also modify oncogene transcription, and in model leukemogenesis experiments GM-CSF has been shown to be a proto-oncogene. However, most evidence is against an autocrine hypothesis of myeloid leukemia based solely on CSF production by emerging leukemic cells. Because the CSFs also have differentiation commitment actions, they can induce differentiation in myeloid leukemic cells, and G-CSF in particular has an impressive capacity to suppress myeloid leukemic populations by this action. The antagonistic actions of the CSFs on myeloid leukemic cells make it difficult to predict whether they will prove to be useful agents in the management of myeloid leukemias.
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PMID:Hemopoietic growth factors and oncogenes in myeloid leukemia development. 332 69

The growth factor-dependent, non-leukemogenic cell line FDC-P1, was converted to an interleukin-3 (IL-3) producing leukemogenic cell line using a retroviral expression vector carrying the IL-3 gene. The new cell line, FDC-P1-IL3 proliferated independently of exogenous IL-3 and its proliferation was inhibited by anti IL-3 antisera. This inhibition could be overcome by addition of GM-CSF to the cultures. The data indicate that insertion of the retroviral expression vector into the genome of FDC-P1 cells has established an autocrine loop involving constitutive secretion of IL-3 and that such a loop can play an important role in leukemogenesis.
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PMID:Generation of an autocrine leukaemia using a retroviral expression vector carrying the interleukin-3 gene. 349 Dec 51

A six-year-old girl with Fanconi anemia (FA) developed acute myeloid leukemia (AML) as the first hematologic manifestation of the syndrome. She remains in remission 18 mo after diagnosis although her management is complicated by unusual sensitivity to chemotherapeutic agents. Marrow cells studied prior to initiation of leukemia therapy showed increased chromosome breakage and an abnormal clone in which a number 7 and a number 8 chromosome were replaced by two marker chromosomes. During the present remission her cultured lymphocytes, bone marrow cells, and fibroblasts showed increased "spontaneous" chromosome breakage as well as enhanced sensitivity to the clastogenic effect of the difunctional alkylating agent diepoxybutane (DEB), features characteristic of FA. Eight months into remission 50% of her marrow cells comprised an abnormal clone, which was monosomic for the number 7 chromosome but had both copies of number 8; in addition a variable number of unique marker chromosomes were present in clonal as well as nonclonal cells. This same marrow sample, upon culture, showed an abnormal growth pattern of CFU-GM, absence of detectable CFU-GEMM and BFUe, non-responsiveness of CFU-GM to inhibition by acidic isoferritins, increased bone marrow acidic isoferritin inhibitory activity, and absence of detectable bone marrow cell-derived GM-CSF. The implications of these findings to leukemogenesis in FA are discussed.
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PMID:Acute myeloid leukemia as the first hematologic manifestation of Fanconi anemia. 695 62

The receptor for human granulocyte/macrophage colony-stimulating factor (hGMR) is composed of two subunits, alpha and beta, which are both required for high-affinity binding of the ligand. To examine the transforming potential of hGMR, we have transfected cDNAs encoding the receptor alpha and beta subunits into NIH 3T3 cells, which normally do not express GMRs. Introduction of the receptor subunits into these cells resulted in focal transformation, which was dependent on the presence of human granulocyte/macrophage colony-stimulating factor (hGM-CSF) in the culture medium. No transformation was observed when hGM-CSF was replaced with other growth factors such as human epidermal growth factor or human interleukin 3 or when cells were transfected with the alpha or beta subunit alone. Individual conditional transformants isolated after transfection expressed functional hGMRs, were susceptible to transformation by picomolar levels of the ligand, and were capable of anchorage-independent growth in soft agar in the presence but not in the absence of hGM-CSF. Biochemical analysis showed that treatment of these cells with hGM-CSF caused a rapid phosphorylation of the beta subunit and other cellular proteins on tyrosine residues, recapitulating some of the events that take place during GM-CSF signaling in myeloid cells. We conclude that coexpression of the alpha and beta subunits of hGMR in established murine fibroblasts is sufficient to reconstitute a functional receptor, which is capable of causing ligand-dependent transformation. The oncogenic potential of hGMR lends support to the hypothesis that its deregulated or abnormal expression may play a role in leukemogenesis.
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PMID:Ligand-dependent transformation by the receptor for human granulocyte/macrophage colony-stimulating factor and tyrosine phosphorylation of the receptor beta subunit. 768 16

Density-dependent cell proliferation and cluster formation are growth phenotypes frequently associated with leukemia cells. The secretion of autocrine growth factor, such as granulocyte-macrophage colony stimulating factor (GM-CSF) and interleukin 1 (IL-1), has been implicated as one possible mechanism in leukemogenesis. In many cases, however, leukemia cells do not appear to produce autocrine growth stimulators. J6-1 is an established human myeloid leukemia cell line that exhibits both density-dependent and cluster-forming growth characteristics. The effect of direct cell-cell contact on J6-1 cell proliferation was investigated. We have isolated from J6-1 cells a membrane-bound factor (designated as MAF-J6-1) that promoted the colony formation by both J6-1 cells and mouse bone marrow CFU-GM. The growth-promoting activity of MAF-J6-1 can be neutralized by either anti-macrophage-CSF (M-CSF or CSF-1) or anti-MAF-J6-1 monoclonal antibodies (MAb), suggesting that MAF-J6-1 is related to M-CSF. Using an immunoblot analysis with anti-MAF-J6-1 MAb, the MW of this membrane-associated factor was estimated to be 80 kDa. Both antibodies also induced a modest growth inhibition on J6-1 cells in vitro. Similarly, addition of exogenous recombinant human M-CSF augmented the colony formation by J6-1 cells, an effect also neutralized by both antibodies. Using an in situ hybridization technique, J6-1 cells were found to express a high level of c-fms proto-oncogene, which encodes the receptor for the M-CSF. Taken together, our results suggest that the membrane-bound MAF-J6-1 promote J6-1 cell proliferation and cluster formation through a 'juxtacrine' mechanism.
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PMID:Enhancement of J6-1 human leukemic cell proliferation by cell-cell contact: role of an M-CSF-like membrane-associated growth factor MAF-J6-1. 796 11


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