Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Thuja polysaccharide g fraction (TPSg) was shown to be an inducer of the CD4+ fraction of the human peripheral blood T-cell subset (1,2). Furthermore, it could be demonstrated that TPSg is a potent inhibitor of the expression of HIV-1-specific antigens and of the HIV-1-specific reverse transcriptase (3). This report deals with the cytokine pattern induced by TPSg in human peripheral blood lymphocyte (PBL) and purified monocyte/macrophage cultures. In addition, a further characterization of the CD4+ T-cell fraction stimulated by TPSg was performed by FACS analysis. TPSg is induces IL-1 beta, IL-2, IL-3, IL-6, gamma-IFN, G-CSF, GM-CSF, and TNF-beta production in PBL cultures; and IL-1 beta and IL-6 in monocyte/macrophage cultures. Enzyme-linked immunosorbent assays (ELISAs) demonstrated that no IL-4 was produced by PBL cultures under TPSg influence.
Leukemia 1992
PMID:Mitogenic activity of high molecular polysaccharide fractions isolated from the cuppressaceae Thuja occidentalis L. enhanced cytokine-production by thyapolysaccharide, g-fraction (TPSg). 160 22

Twenty patients with leukaemia received recombinant human GM-CSF (rhGM-CSF) after allogeneic bone marrow transplantation (BMT) in a double blind controlled trial, with a significant promotion of granulopoiesis when compared with 20 control patients. The follow-up in survivors is now sufficiently long to assess the potential for promotion of relapse in the patients with myeloid leukaemias. Six patients with myeloid leukaemias are alive 22-38 months after transplantation. Eight other patients with myeloid leukaemias died within 12 weeks of transplantation without active active disease. None of these 14 patients with myeloid leukaemias have relapsed. This study supports the view that rhGM-CSF does not increase the probability of relapse after allogeneic BMT in patients with myeloid leukaemia.
 ...
PMID:No increase in relapse in patients with myeloid leukaemias receiving rhGM-CSF after allogeneic bone marrow transplantation. 162 35

The binding of haemopoietic growth factors and cytokines to specific receptors triggers a cascade of intracellular events which results in cell proliferation and differentiation. The knowledge of ligand-receptor-signal pathways is not only important in understanding the pathophysiology of malignant disease but also essential for devising future therapeutic strategies. The advent of recombinant technology has made it possible to test the efficacy of selective differentiation therapy, and haemopoietic growth factors are undergoing clinical trials for a number of indications. In addition, increasingly the receptors for haemopoietic growth factors and cytokines have come under scientific scrutiny. Recently receptors for IL-2 alpha, IL-2 beta, IL-3, IL-4, IL-5, IL-6, IL-7, erythropoietin, G-CSF and GM-CSF have been isolated and cloned. It has become apparent that they have structural homology that is shared by receptors for growth hormone and prolactin, and this receptor group makes up the new cytokine receptor superfamily. The finding of sequence homology within these receptors suggests their evolutionary relationship. These receptors are transmembrane proteins 257-856 amino acids and their extracellular ligand-binding domain contains four conserved cysteine residues and a Trp-Ser-X-Trp-Ser motif. The secondary structure of the extracellular domain is made up of alpha-helices. High and low affinity binding forms exist for all these receptors. Binding affinity may depend on the formation of receptor heterodimers or multimers, association with other membrane proteins or differential glycosylation. Soluble receptor forms have been described for IL-2 alpha, IL-4, IL-5, IL-6 and IL-7. It is not known whether they are actively secreted or represent the degradation products of cell turnover. Their function may be to mop up excess cytokines and thereby confine the cytokine response. There is no sequence homology of the intracytoplasmic domains although several are rich in proline and serine residues, which may be important in mechanisms of signal transduction. No receptor in this superfamily functions as a receptor tyrosine kinase or has intrinsic protein tyrosine kinase activity. Detailed study of individual receptors holds clues to the regulation of receptor expression, ligand-receptor interactions and mechanisms involved in signal transduction. Such knowledge might explain the pleotropic effects cytokines may have on different cell types and their overlap in biological functions. Elevated levels of soluble IL-2 alpha receptor (Tac) are detected in hairy cell leukaemia, lymphomas and adult T-cell leukaemia (TL), and levels reflect tumour burden.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:The cytokine receptor superfamily. 166 10

For granulocytic-macrophage progenitor populations and their progeny, five glycoproteins have been identified: GM-CSF, G-CSF, multi-CSF, M-CSF and IL-6 that can regulate their proliferative activity, maturation and functional activities. The same glycoproteins also have a capacity to induce irreversible differentiation commitment in normal bipotential granulocyte-macrophage progenitors and in some myeloid leukaemic cell lines, which suggests that common cellular processes exist in both situations. The leukaemia inhibitory factor (LIF) is a glycoprotein, with intriguing properties, which can either induce differentiation in some myeloid leukaemic cell lines or prevent differentiation in normal totipotential embryonic stem cells. The data from the LIF studies suggest a genetic mechanism controlling self-generation that is relatively simple and may be common to all cells. However, the actual cellular response observed appears to depend on the nature of the responding cell.
 ...
PMID:The induction and inhibition of differentiation in normal and leukaemic cells. 169 Sep 2

Progress in genetics now enables the synthesis of molecules acting on the regulation of the immune system which are called cytokines. Currently there are several cytokines, Interferon (IFN), Interleukin 2 (IL2), tumour necrosis factor (TNF) as well as haematopoietic growth factors and these are the object of study in clinical trials. Interferon has already been used in the therapy of hairy cell leukaemia, Kaposi sarcoma associated with AIDS(SIDA) and metastasis of malignant melanoma. Interleukin 2 allows for an increase in the cytotoxic activity of NK cells in producing LAK cells, the lymphocyte infiltrating the tumour (TIL). Therapeutic combinations combining IL2 associated with LAK or of TIL have been evaluated in some private studies. These treatments have shown some interesting response levels on those tumours which are usually resistant, such as malignant melanoma or carcinoma of the kidney. TNF is active in vitro on human tumours; its potential toxicity is important; it is the object of a phase 1 clinical trial. Haematopoietic growth factors, G-CSF and GM-CSF, stimulate the production of leucocytes which will be valuable to correct toxic affects on the marrow during chemotherapy. This will enable chemotherapy to be given at a high dose.
 ...
PMID:[Immunotherapy of cancer using cytokinins. Use and perspectives in lung oncology]. 169 91

Monoclonal antibody YB5.B8 was previously shown to inhibit haemopoietic colony formation in response to a complex growth factor supplement in vitro (Cambareri A. C., Ashman L. K., Cole S. R. & Lyons A. B. (1988), Leukemia Res. 12, 929). We now report studies of the effect of the antibody on colony formation by normal human bone marrow cells in response to recombinant human colony-stimulating factors GM-CSF, G-CSF and IL-3. MAb YB5.B8 significantly reduced the yield of colonies of all types examined (granulocyte-macrophage, granulocyte, macrophage and eosinophil) in response to GM-CSF but not to IL-3 or G-CSF. However, MAb YB5.B8 failed to influence the proliferation of the myelomonocytic leukaemia cell line RC-2A in response to GM-CSF, G-CSF or IL-3. Direct binding studies demonstrated the presence of low numbers of receptors for GM-CSF on RC-2A cells, however, the binding of this cytokine was not influenced by co- and/or pre-incubation with MAb YB5.B8. Therefore the antigen identified by YB5.B8 is probably not a receptor for GM-CSF and may indirectly influence the response of normal haemopoietic progenitors to this cytokine.
 ...
PMID:A monoclonal antibody that inhibits the action of GM-CSF on normal but not leukaemic progenitors. 169 6

A rapid decrease in expression of the oncogene c-myc has been associated with the induction of differentiation of HL-60 human leukemia cells. In this manner, the treatment of a hypoxanthine phosphoribosyltransferase (HPRT)-deficient HL-60 variant (HL-60/var) with 6-thioguanine (TG) was accompanied by lower c-myc mRNA levels. This occurred in the absence of 6-thioguanosine 5'-monophosphate (TGMP) synthesis and without alterations in cellular nucleotide pool sizes. Paradoxically, inhibition of c-myc expression in the wild type HL-60 (HL-60/wt) cell, which is only weakly induced to differentiate by TG, was 5-fold more sensitive to the thiopurine (IC50 = 35 microM). Furthermore, inosine, which blocks the formation of TGMP and enhances the extent of differentiation of HL-60/wt cells, decreased the sensitivity of c-myc expression in the HL-60/wt to TG. These actions of TG and inosine on c-myc were also observed in the human colon carcinoma cell line COLO 320, further dissociating some of the effects of TG on c-myc expression from granylocytic differentiation. The hematopoietic granulocyte-macrophage colony stimulating factor (GM-CSF) elevated c-myc expression and antagonized the actions of TG on c-myc in the HL-60 cells. GM-CSF more readily antagonized the inhibitory action of TG in the HL-60/var cell line when compared to the HL-60/wt cells, restoring c-myc levels to that of the untreated controls. Hence, TG inhibited c-myc expression by two distinct mechanisms in cells which express high levels of the oncogene: a TGMP-dependent, differentiation-independent process with an IC50 of 35 microM, and a TGMP-independent action with an IC50 of 175 microM that was associated with induction of differentiation and was reversed more readily by GM-CSF.
 ...
PMID:Inhibition of c-myc expression in human promyelocytic leukemia and colon adenocarcinoma cells by 6-thioguanine. 170 32

The controversial role of interleukin-6 (IL-6) as an auto- or paracrine growth factor for human multiple myeloma (MM) cells was studied using a panel of six well characterized feeder-cell dependent and independent MM cell lines as models. With respect to the effect of IL-6 on growth and survival, three types of lines were found: (1) U-1958, dependent on IL-6 both for growth and survival; (2) U-1996, dependent on IL-6 for growth but not survival; and (3) U-266-1984, Fravel, L363, and Karpas 707, independent of IL-6. Feeder-cell supernatants were as efficient as feeder-cell monolayers in stimulating growth and contained IL-6 as the only growth promoting activity. IL-6 was growth stimulatory and sustained the growth of U-1958 only when the medium contained fetal calf serum. The nature of the serum factor(s) is unknown, but it was excluded to be the IL-6 carrier protein a2-macroglobulin. IL-1, IL-2, IL-3, TNF-alpha, GM-CSF, IGF-1, and insulin were neither co-stimulatory with IL-6 nor stimulated growth on their own. Only U-266-1984 expressed IL-6 mRNA. IL-6 receptor mRNA was expressed in all lines except the L363 and Fravel. We conclude that the response to IL-6 is heterogeneous among the MM lines and that IL-6 acts as a paracrine growth factor for two of six lines. In a third line, U-266-1984, the IL-6 mRNA expression suggests the possibility of an autocrine growth stimulation.
Leukemia 1991 Mar
PMID:Heterogeneity in response to interleukin 6 (IL-6), expression of IL-6 and IL-6 receptor mRNA in a panel of established human multiple myeloma cell lines. 170 69

Leukopenia or pancytopenia as a result of bone marrow dysfunction are manifestations of various diseases or complications of therapeutic regimens. The spectrum of diseases associated with leukopenia is wide and includes congenital as well as acquired neutropenias secondary to conditions such as myelodysplastic syndromes, AIDS, malignant tumors with or without chemotherapy-enhanced neutropenia, bone marrow transplantation or therapeutic or accidental radiation. The morbidity and mortality of infectious diseases is greatly enhanced during neutropenic phases. Over the last few years attempts have been made to shorten the duration and lessen the severity of neutropenia in patients with the above conditions by administration of Granulocyte Macrophage Colony Stimulating Factor (G-CSF). Both cytokines were successfully tested in phase I and II trials. Treatment with GM-CSF or G-CSF results in a dose-dependent increase of the neutrophil count. GM-CSF also increases the number of eosinophils and monocytes in peripheral blood. The effect of both cytokines on the neutrophil count is transient as long as the underlying disease persists. This prompted the institution of maintenance therapy, which has been successfully used with either cytokine. Long-term treatment is usually well tolerated and results in a reduction in the frequency of infections as well as in the duration of antibiotic treatments. Side effects of GM-CSF or G-CSF are usually mild and include fever, myalgia, bone pain, and erythema. A number of patients developed dyspnea, hypotension, sweating, flushing and erythema after the first dose of GM-CSF in each treatment cycle. This first-dose reaction occurs more frequently after intravenous than reactions were reported with G-CSF. Some patients with myelodysplastic syndrome progressed to acute myeloic leukemia during or after treatment with GM-CSF or G-CSF. Most of these patients presented with an increased fraction of blasts in the bone marrow, which preceded the treatment with the colony stimulating factors. Since GM-CSF and possibly G-CSF may increase the risk of developing acute leukemia in patients with myelodysplastic syndrome, it appears prudent to limit the use of these cytokines in patients with this disease. The subcutaneous route of administration appears to be preferable to intravenous administration, since the incidence and severity of side effects are reduced. While many questions concerning dosage, long-term therapy and combination therapy still remain unanswered, the information presented in this review concerning the clinical use of these cytokines warrants an optimistic outlook.
 ...
PMID:[GM-CSF and G-CSF: cytokines in clinical application]. 170 94

The effects of human recombinant interleukin 4 (rIL-4) on the growth of leukaemic blast progenitors were investigated. Cells obtained from 20 acute myeloblastic leukaemia (AML) patients were evaluated using the blast colony assay in methylcellulose and suspension cultures. While rIL-4 by itself did not show any colony stimulatory activity in the blast colony assay, it suppressed the blast colony formation in methylcellulose stimulated with G-CSF, GM-CSF or IL-3 in 14 patients. In another six patients, rIL-4 enhanced blast colony growth in four patients or did not show any significant effect with any CSF in two patients. In suspension cultures of 12 cases studied, the effects of rIL-4 on the clonogenic cell recoveries were essentially similar to the results of the blast colony assay in each case. In three patients, rIL-4 augmented the differentiation of the leukaemic cells to monocyte lineage. Further, the clinical outcome was significantly different between the patients whose blast progenitors were stimulated by rIL-4 and the patients whose blast progenitors were suppressed by rIL-4 (P less than 0.05); three out of four patients in the former group failed in achieving complete remission (CR), while 12 out of 14 patients in the latter group achieved CR. The results show that the effects of IL-4 on leukaemic blast progenitors were diverse and the responsiveness to IL-4 may be correlated with the prognoses of the patients.
 ...
PMID:Effects of recombinant interleukin 4 on the growth and differentiation of blast progenitors stimulated with G-CSF, GM-CSF and IL-3 from acute myeloblastic leukaemia patients. 171 23


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>