Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026986 (myelodysplastic syndrome)
 14,926 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Human recombinant stem cell factor (rSCF) was tested for its capability of improving the defective growth of hemopoietic progenitors in 28 cases of myelodysplastic syndromes (MDS). In vitro growth and response to rSCF were quite variable. However, in most cases, rSCF stimulated CFU-GM growth induced by rG-CSF, rGM-CSF, rIL-3, 5637 conditioned medium (50-1400% enhancement). rSCF effect was slightly more evident on day 14 CFU-GM and in the presence of rIL-3. BFU-E growth induced by rEPO or rIL-3 + rEPO was enhanced by rSCF in about 50% of cases, in linear correlation with the levels of patients' hemoglobin. rSCF did not increase CFU-E growth, whereas it slightly stimulated CFU-Mk in 33% of the cases. EPO, SCF and, particularly, their combination, enhanced the recovery of normal CFU-E and BFU-E after 7 days of liquid culture. This was less evident in cultures of MDS patients. Conversely, CFU-GM generation in long term liquid cultures, although highly variable, was stimulated by rSCF and, above all, by rSCF + rG-CSF, similarly to what was observed with normal bone marrow samples. SCF seems to enhance in vitro erythropoiesis only in MDS cases presenting without severe anemia. It has little effect on megakaryocytopoiesis, while it seems to be more active on CFU-GM growth and maintenance.
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PMID:Stem cell factor improvement of proliferation and maintenance of hemopoietic progenitors in myelodysplastic syndromes. 750 32

In vitro growth of primitive hematopoietic progenitors is severely impaired in the myelodysplastic syndromes (MDS). To determine if the c-kit ligand mast cell growth factor (MGF) can improve progenitor growth in MDS, we evaluated in vitro responsiveness of bone marrow progenitors from 25 patients to MGF and/or GM-CSF, interleukin-3 (IL-3) and PIXY 321, and examined the relationship between progenitor response and cellular expression of the c-kit receptor. MGF and erythropoietin gave rise to macroscopic colonies and dose-dependently increased CFU-GEMM and BFU-E up to 27-fold in 15 (60%) and 20 (80%) patients, respectively. Among 17 patients with absent growth in lymphocyte-conditioned media, MGF stimulated CFU-GEMM recovery in 59%, compared to 23% with PIXY 321, 12% with IL-3 and 8% with GM-CSF. Cytokine combinations did not augment recovery of erythropoietin-dependent progenitors above that achieved with MGF alone. MGF and/or IL-3 were comparatively weak stimulants of CFU-GM formation, whereas GM-CSF and PIXY in combination with MGF increased colony number 2- to 15-fold in 60 and 70% of patients, respectively, while preserving maturation competence as evidenced by colony composition and increased colony/cluster ratio. The stimulatory effects of MGF were observed in all morphologic categories of MDS except chronic myelomonocytic leukemia. A mononuclear cell population expressing the c-kit receptor was identified by flow cytometry in 57% of cases. Neither SR-1 reactivity nor cytogenetic pattern predicted progenitor response to MGF. These data indicate that MGF improves the colony-forming capacity of hematopoietic progenitors in MDS and is a potent co-stimulant of multipotent and committed progenitor recovery. The heterogeneity in MGF responsiveness implies an intrinsic defect in growth regulation not explained by cellular loss of c-kit display.
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PMID:Mast cell growth factor (c-kit ligand) restores growth of multipotent progenitors in myelodysplastic syndrome. 751 48

The in vitro colony-forming capacities of marrow CD34-positive (CD34+) cells from 25 patients with myelodysplastic syndromes (MDS) were studied. In all patients this purified cell population showed erythroid (burst-forming unit erythroid; BFU-E) or non-erythroid colony growth, both of which were more restricted than non-purified mononuclear cell population under stimulation with erythropoietin (EPO) or granulocyte/macrophage colony-stimulating factor (GM-CSF) alone. MDS patients examined were put into two groups; refractory anemia (RA) or RA with ringed sideroblasts (RA/RARS) and RA with excess of blasts (RAEB) or RAEB in transformation (RAEB/RAEB-t). The CD34+ cells of both RA/RARS and RAEB/RAEB-t exhibited a similarity to the cells of normal individuals in their responsiveness to the addition of interleukin 6 (IL-6), IL-3 or stem cell factor (SCF). SCF caused powerful but highly variable responses in both erythroid and nonerythroid colony formation as compared with IL-6 or IL-3. We demonstrated that MDS marrow hematopoietic progenitor cells reactive to GM-CSF or EPO were additionally stimulated with early-acting hematopoietic growth factors including IL-6, IL-3 and SCF in a fashion similar to those of normal individuals.
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PMID:Growth analysis of marrow CD34-positive hematopoietic progenitor cells in patients with myelodysplastic syndromes. 751 49

Recombinant human granulocyte colony-stimulating factor (rhG-CSF) and erythropoietin (rhE-PO) were used to treat ten patients with myelodysplastic syndromes (MDS). None of the patients showed a favorable response in erythrocyte and platelet counts following 10 weeks' treatment, although favorable responses in neutrophil counts were observed in eight of ten patients (80.0%) and in seven of eight patients (87.5%) following 2 weeks' and 10 weeks' treatment, respectively. However, one patient with refractory anemia had a delayed favorable response in erythrocyte and neutrophil counts at week 14 in spite of the cessation of combination therapy at week 10. These results indicate that combination therapy with rhG-CSF and rhEPO is not beneficial to patients with MDS, based on the presently used protocol.
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PMID:Failure of combination therapy with recombinant granulocyte colony-stimulating factor and erythropoietin in myelodysplastic syndromes. 751 90

To evaluate the effects of colony-stimulating factors (CSFs) on pathological cells from myelodysplastic syndromes (MDS), the blast cells from 19 MDS patients (eight low-risk MDS, six high-risk MDS, and five leukemic transformation of MDS [LT-MDS]) and four normal volunteers were successfully enriched by separating CD34-positive cells by the use of immunomagnetic beads, and their responsiveness to granulocyte or granulocyte-macrophage CSF (G-CSF or GM-CSF) was examined in short-term liquid suspension culture. The proliferation of MDS blast cells was clearly promoted by these CSFs in all cases examined, but considerable percentages of them often remained immature compared with the favorable maturation of normal blast cells, especially in the more advanced disease groups (LT-MDS and high-risk MDS) that included two prominent cases with a remarkable blast cell growth without maturation induction by CSFs. The expression of esterase activities was rather sluggish in the MDS cases, in contrast to normal expression. These data showed that MDS blast cells proliferate in response to CSFs but that maturation is less than that observed with normal blast cells in vitro. Much care should be taken with in vivo application of CSFs to high-risk MDS patients.
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PMID:Altered responses of purified blast cells from the myelodysplastic syndromes to colony-stimulating factors in vitro: comparison with normal blast cells. 751 87

Administration of G- and GM-CSF increases the neutrophil counts in a number of clinical situations. GM-CSF shows the additional effect of increasing the number of monocytes and eosinophil granulocytes. Both G- and GM-CSF affect of neutrophil functions, in the case of GM-CSF there are some potentially negative effects on neutrophil migration and adhesiveness. The clinical relevance of the various effects on mature haematopoietic cells is not fully understood. Clinical data with G-CSF treatment indicate that increased levels of neutrophil granulocytes following cytotoxic chemotherapy may translate into clinical benefit such as a decreased rate of neutropenic infection and an increased cytotoxic chemotherapy dose even though the data are conflicting and the risk of "laboratory cosmetics" is apparent. Regarding treatment with GM-CSF following chemotherapy, the clinical benefit is unclear. The clinical benefit of GM-CSF-induced monocytes and eosinophils is unknown. G- and GM-CSF accelerates neutrophil recovery following autologous or allogeneic BMT. The influence on neutropenic infections is, however, less impressive. Pretreatment with G- or GM-CSF increases the yield of peripheral stem cell harvest, thereby reducing the number of leukaphereses needed. Transplantation of G- and GM-CSF primed autologous peripheral stem cells tends to reduce the period of post-transplant cytopenia, particularly thrombocytopenia, in comparison with traditional ABMT. In patients with MDS, G- and GM-CSF appear to increase the number of neutrophil granulocytes and there is some evidence that patients with severe infectious problems will benefit from this treatment. However, little influence was seen on the main clinical problems with these patients, which are anaemia and thrombocytopenia. In conclusion, G- and GM-CSF are two different proteins with different properties in vivo and in vitro. GM-CSF has, compared with G-CSF, more complex pharmacological effects and a more trouble-some side-effect profile. Early clinical development indicates that both compounds have a substantial influence on the levels of certain blood cells. Whether the increases in different blood cells translate into long-term clinical benefit for greater patient groups is the focus of ongoing research. The effects of G- and GM-CSF may be potentiated by other cytokines, an area which is presently being explored.
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PMID:G- and GM-CSF in oncology and oncological haematology. 751 79

We studied mRNA expression of the cytokine granulocyte-colony stimulating factor (G-CSF), interleukin-1 beta (IL-1 beta), IL-6, IL-8 and stem cell factor of stromal cells derived from bone marrows of nine normal volunteers, eight patients with aplastic anaemia (AA) and seven patients with myelodysplastic syndrome (MDS). The proportion of endothelial cells, macrophages, fibroblast-like cells and adipocytes in stromal cells showed no differences between normal volunteers and the patients. Levels of cytokine mRNA expression were determined by reverse transcription-polymerase chain reaction. Spontaneous expression occurred and this was augmented by LPS stimulation in cells of all the normal volunteers and in most patients. When stimulated by LPS, the mean G-CSF and IL-1 beta mRNA expressions in patients with AA were significantly higher than normal volunteers, but there was one patient showing lower IL-1 beta, IL-6 and IL-8 expression with no response to LPS. LPS-induced IL-6 and IL-8 expression of two patients with MDS were significantly higher than normal. The spontaneous and LPS-induced protein concentration of G-CSF, IL-6 and IL-8 in culture supernatants from 15, 10 and four patients, correlated well with the mRNA expression. The correlation coefficients were 0 x 92, 0 x 78 and 0 x 91, respectively. In conclusion, there were a few patients whose aetiology appeared to be reduction of stromal cytokine expression in AA, but most patients with AA and MDS expressed normal or high levels of cytokine mRNA.
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PMID:Cytokine mRNA expression of bone marrow stromal cells from patients with aplastic anaemia and myelodysplastic syndrome. 752 19

Using clonogenic assay we investigated the effect of stem cell factor (SCF) on the in vitro growth of clonogenic precursor cells from acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) in the presence or absence of recombinant human erythropoietin (rhEpo) or recombinant human granulocyte colony-stimulating factor (rhG-CSF). SCF as a single factor did not induce significant colony formation, and even in the presence of rhEPO or rhG-CSF it very weakly stimulated erythroid colony formation and was rarely capable of inducing myeloid colony formation by clonogenic leukemic cells. In culture dishes supplemented with SCF, both myeloid and erythroid colony formations were dramatically enhanced in MDS, regarding both colony number and size. Colony-formation abilities by MDS progenitors were improved following costimulation with SCF and rhEpo. These results suggest that SCF may have a therapeutic role in restoring hematopoiesis in patients with MDS.
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PMID:Effect of stem cell factor (c-kit ligand) on clonogenic leukemic precursor cells: synergy with other hematopoietic growth factors. 752 82

Congenital neutropenias include a heterogenous group of diseases characterized by a decrease in circulating neutrophils. In phase I/II/III studies in patients with severe congenital and cyclic neutropenia, treatment with recombinant human granulocyte colony-stimulating factor (r-metHuG-CSF) resulted in a rise in the absolute neutrophil counts (ANC) and a reduction in infections. We report the effects of long-term safety of subcutaneous r-metHuG-CSF administration in 54 patients (congenital n = 44. cyclic n = 10) treated for 4-6 years. A sustained ANC response was seen in 40/44 severe congenital neutropenia patients and 10/10 cyclic neutropenia patients. Two patients required an increase of > 25% in dose to maintain a clinical response; one patient became refractory to therapy. A significant decrease in the incidence of severe infections and the need for intravenous antibiotics was noted. Significant adverse events noted which may or may not be related to therapy included: osteopenia (n = 15), splenomegaly (n = 12), hypersplenism (n = 1), vasculitis (n = 2), glomerulonephritis (n = 1), BM fibrosis (n = 2), MDS/leukaemia (n = 3), and transient inverted chromosome 5q with excess blasts (n = 1). R-metHuG-CSF has been well tolerated in the majority of patients and resulted in a long-term improvement in their clinical status.
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PMID:Long-term safety of treatment with recombinant human granulocyte colony-stimulating factor (r-metHuG-CSF) in patients with severe congenital neutropenias. 1093 Oct 6

Twenty-one patients with myelodysplastic syndrome (MDS) or overt leukemia resulting from MDS were treated with recombinant human granulocyte colony-stimulating factor (rhG-CSF) and cytosine arabinoside (Ara-C). Ara-C was administered in a dose of 20 mg/m2 every 12 h for 5 days and after 2 days 125 micrograms of rhG-CSF was administered for 10 days. After recovery of the leukocyte count the therapy was repeated, doubling the dose of Ara-C serially when possible. Of 13 patients with MDS, four achieved complete remission (CR), two good response (GR), two minor response (MR), and five no response (NR). Of eight patients with overt leukemia from MDS, only one with hyperplastic bone marrow achieved a partial response (PR) and the remaining seven achieved NR. The efficacy of the combination of rhG-CSF and Ara-C in the treatment of MDS and its leukemic phase is discussed, including at which time rhG-CSF should be administered: before, after or concomitantly with Ara-C. Multicenter randomized studies are needed in the evaluation of this combination therapy.
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PMID:Treatment with cytosine arabinoside and granulocyte colony-stimulating factor in patients with myelodysplastic syndrome and its leukemic phase. 753 31


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