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

Thirty-four patients with MDS or AML following MDS were studied with regard to survival, peripheral blood values and bone marrow morphology. The effects of 1,25 dihydroxyvitamin D3 (D3) on differentiation (NBT positivity) and proliferation (3H-thymidine incorporation) were studied in suspension cultures of bone marrow cells. Twelve bone marrow donors served as controls. Normal cells showed spontaneous differentiation in vitro, but only 2/12 were induced to differentiation by D3. Myelodysplastic cells did not differentiate spontaneously, but cells from 18/34 patients differentiated after incubation with D3. Normal cells showed increased proliferation, myelodysplastic cells showed a heterogeneous response and leukemic cells reacted with decreased proliferation after D3 incubation. Poor survival was associated with low platelet counts, high percentage of bone marrow blasts (BM blast %), low spontaneous in vitro proliferation and absence of hypogranulation of myeloid cells. Platelet counts and hypogranulation retained their predictive value in a multi-variate analysis. Progression to AML was predicted by a high BM blast % and low scores for erythroid and total dysplasia. In conclusion, the pattern of in vitro proliferation showed prognostic value while the pattern of vitamin D3-induced differentiation failed to correlate to other parameters. An estimation of bone marrow dysplasia can be used to predict the development of AML. Our results add to the information about the biology of MDS and may be important for the evaluation of therapeutic trials.
 ...
PMID:In vitro suspension culture reactions to 1,25 dihydroxyvitamin D3 in relation to bone marrow morphology and prognosis in patients with myelodysplastic syndromes. 162 79

Mast cell growth factor (MGF), the ligand for the c-kit receptor, has been shown to be a hematopoietic growth factor that preferentially stimulates the proliferation of immature hematopoietic progenitor cells (HPC). We studied the effect of MGF on the in vitro growth of clonogenic leukemic precursor cells in the presence or absence of interleukin-3 (IL-3), granulocyte-macrophage colony-stimulating factor (GM-CSF), and/or erythropoietin (EPO). Leukemic blood and bone marrow cells from patients with various types of acute myeloid leukemia (AML), chronic myeloid leukemia (CML) in chronic phase, as well as bone marrow samples from patients with myelodysplastic syndromes (MDS) were studied. MGF as a single factor did not induce significant colony formation by clonogenic leukemic precursor cells. In the presence of IL-3 and/or GM-CSF, MGF weakly stimulated the colony formation by clonogenic precursor cells from patients with AML. In contrast, in the presence of IL-3 and/or GM-CSF, MGF strongly induced both size and number of leukemic colonies from patients with CML in chronic phase. Furthermore, in the presence of EPO, MGF strongly stimulated erythroid colony formation by CML precursor cells. Cytogenetic analysis of the colonies showed that all metaphases after 1 week of culture were derived from the leukemic clone. In patients with MDS, MGF strongly stimulated myeloid colony formation in the presence of IL-3 and/or GM-CSF (up to fourfold), and erythroid colony formation in the presence of EPO (up to eightfold). Not only the number, but also the size of the colonies increased. In the presence of MGF, the percentage of normal metaphases increased in three patients tested after 1 week of culture compared with the initial suspension, suggesting that the normal HPC were preferentially stimulated compared with the preleukemic precursor cells. In the absence of exogenous EPO and in the presence of 10% human AB serum, MGF in the presence of IL-3 and/or GM-CSF induced erythroid colony formation from normal bone marrow and patients with MDS or CML, illustrating that MGF greatly diminished the EPO requirement for erythroid differentiation. These results indicate that MGF may be a candidate as a hematopoietic growth factor to stimulate normal hematopoiesis in patients with acute myeloid leukemia, or with myelodysplastic syndromes.
 ...
PMID:Effect of mast cell growth factor (c-kit ligand) on clonogenic leukemic precursor cells. 163 26

A patient with acute myelomegakaryocytic leukemia (AMMgL), which developed from myelodysplastic syndrome (MDS) after chemotherapy against complicated small cell lung cancer, is reported. The patient was a 66 year-old male, who first presented with moderate macrocytic anemia. Bone marrow aspiration showed absolute erythroid hypoplasia and morphological abnormalities were found in erythroid, granuloid and megakaryocytic lineage cells. Iron utilization studies using radioisotope showed ineffective hematopoiesis. He was diagnosed as having MDS (refractory anemia) and treated with prednisolone, fluoxymesterone, and transfusions. After 3 years, small cell lung cancer was found, but he achieved complete remission with chemotherapy. Since then, pancytopenia progressed with myelofibrosis. Abnormal blasts were found in peripheral blood and gradually increased. He finally died from a blastic crisis resulting in gastric bleeding. The blasts were peroxidase negative, platelet peroxidase positive (10%), and glycoprotein II b/III a antibody positive, indicating megakaryoblasts.
 ...
PMID:[Acute myelomegakaryocytic leukemia developed from myelodysplastic syndrome after chemotherapy against complicated small cell lung cancer]. 164 8

We evaluated the effects of recombinant human granulocyte colony stimulating factor (rhG-CSF) and granulocyte-monocyte colony stimulating factor (rhGM-CSF) on the in vitro proliferative, differentiative, and regenerative responsiveness of marrow cells from myelodysplastic syndrome patients (MDS) in comparison to those from normal individuals. Our studies showed decreased primary clonogenicity of myeloid (CFU-GM) and erythroid (BFU-E) hemopoietic progenitor cells from the MDS patients. rhGM-CSF had more potent stimulatory effects than rhG-CSF for MDS marrow CFU-GM growth; no enhanced cellular proliferation in the MDS patients was observed in liquid culture with either rhGM-CSF or rhG-CSF. Decreased myeloid clonal cell self-generation and/or recruitment occurred in the MDS patients upon exposure to either rhG-CSF or rhGM-CSF. rhG-CSF demonstrated more potent granulocytic differentiation effects than rhGM-CSF both for normals and MDS patients using marrow enriched for immature myeloid cells with lesser differentiation noted for MDS. Cytogenetic abnormalities, present with or without additional normal karyotypes in native marrow of four MDS patients, persisted after culture with rhG-CSF, indicating induced differentiation of both normal and abnormal clones. Although proliferative and differentiative effects were seen with both factors these data show MDS marrow cells in vitro to have predominantly differentiative responsiveness to rhG-CSF and proliferative responsiveness to rhGM-CSF.
 ...
PMID:Effects of recombinant human granulocyte colony stimulating factor and granulocyte-monocyte colony stimulating factor on in vitro hemopoiesis in the myelodysplastic syndromes. 169 Mar 18

The effects of four recombinant hemopoietic growth factors (HGF) and of the impure factor HTB9 on proliferation and maturation of marrow myeloid (CFU-GM) and erythroid (BFU-E) progenitor cells were studied in 22 cases of myelodysplastic syndromes (MDS). In most cases, IL-3, GM-CSF and G-CSF increased significantly the number of myeloid colonies, the best combination being IL-3 + GM-CSF. A significant increase in the myeloid colony/cluster ratio was also noted, but cytological examination of colony cells showed little maturation. The analysis of myeloid colony surface markers with four monoclonal antibodies (to CD13, CD15, CD33 and CD34) showed minor modifications with an increase of CD13 and CD15 in about one third of cases when compared to control without HGF. Erythroid colonies were obtained in one case with erythropoietin alone, and in 19 cases with the addition of GM-CSF and/or IL-3. In short-term liquid cultures, IL-3, GM-CSF and G-CSF increased 3H-thymidine incorporation. We conclude that progenitor cells of most MDS are able to proliferate in the presence of HGF, with wide case-to-case variations. However, the pattern of growth remains abnormal when compared to normal marrow. Although the combination of IL-3 and GM-CSF is the most efficient, there is a large overlap in the stimulating effects of all factors studied.
 ...
PMID:In vitro effects of recombinant hemopoietic growth factors on progenitor cells from patients with myelodysplastic syndromes. 170 6

In an attempt to identify prognostic factors for survival and leukemic transformation, 235 untreated patients with primary myelodysplastic syndromes (MDS) were analyzed in a single center retrospective study. To the well known FAB classification of MDS a supplementary group of patients with pure sideroblastic anemia (PSA) was added, characterized by the absence of dysplastic features of non-erythroid cells. Accordingly, the morphological subtypes were refractory anemia (RA), n = 55; PSA, n = 40; RA with ring sideroblasts (RARS), n = 33; RA with excess of blasts (RAEB), n = 53; RAEB in transformation (RAEB/T) n = 29; and chronic myelomonocytic leukemia (CMML), n = 25. Having screened 28 clinical, cytological, and laboratory parameters by univariate analysis, multiple regression analysis identified six variables with independent prognostic value: percentage of bone marrow blasts, serum LDH activity, PSA, hemoglobin concentration, age, and platelet count. If patients with PSA were excluded, the FAB classification no longer contributed independent prognostic information. Based on the results of this multivariate analysis, a simple scoring system was devised for predicting the survival of patients with MDS. A score of unity was allocated to each of the following parameters: bone marrow blasts greater than or equal to 5%, LDH greater than 200 U/I, hemoglobin less than or equal to 9 g/dl, and platelets less than or equal to 100 x 10(9)/I. As a function of their total score, patients were divided into three risk groups (group A, score 0; group B, score 1-2; group C, score 3-4), which differed significantly in both survival and rates of leukemic transformation. The cumulative survival 2 years after diagnosis was 91% in group A, 52% in group B, and 9% in group C (p less than 0.00005). The actuarial risk of transformation to acute myeloid leukemia at 2 years was 0, 19, and 54%, respectively (p less than 0.05). The inclusion of LDH enzyme levels qualified this scoring system for an accurate assessment of patients with CMML whose prognosis is viewed too favorably when rated by other scores. Furthermore, this score was able to identify those patients with RA and RARS who, without showing an excess of marrow blasts, have an unfavorable prognosis.
 ...
PMID:Primary myelodysplastic syndromes: analysis of prognostic factors in 235 patients and proposals for an improved scoring system. 173 14

Relapse continues to be a problem after bone marrow transplantation (BMT) for hematologic malignancies, particularly in recipients of autologous or T-cell-depleted allogeneic grafts and in patients with advanced disease. Interferon (IFN) has shown antiproliferative activity in several malignant hematologic diseases and potentially may be of benefit when administered early after BMT when the number of residual cells is minimal. We tested in a phase I study the maximum tolerated daily dose of recombinant IFN alpha-2b in patients who had received a transplant for a disease at high risk for relapse (acute myeloid leukemia or non-Hodgkin's lymphoma beyond first remission, advanced myelodysplastic syndrome, acute lymphoblastic leukemia at any stage, chronic myeloid leukemia in accelerated or blast phase. Recombinant IFN alpha-2b was started at a dose of 0.5 x 10(6) IU/m2 and escalated by 0.5 x 10(6) IU/m2 in groups of three or four patients. The intention was to administer IFN as soon as stable engraftment after BMT was achieved (defined as an absolute neutrophil count of greater than 2.0 x 10(9)/L and platelet count greater than 100 x 10(9)/L for 5 consecutive days) and continued for 2 months. A total of 14 patients were enrolled after autologous (n = 3) or allogeneic (n = 11) BMT. Dose-limiting toxicity was myelosuppression. Significant (grade 2 to 4) neutropenia and thrombocytopenia led to discontinuation or dose reduction in five of eight patients receiving 1.5 x 10(6) or 2 x 10(6) IU/m2 IFN. Mild to moderate (grade 1 or 2) anorexia, weight loss, and fatigue occurred in the majority of patients independent of the IFN dose. De novo acute GVHD responsive to steroid treatment developed in 3 of 11 allograft recipients. Natural killer (NK) cell function was low before IFN treatment and was not improved with the cytokine. Conversely, interleukin-2-activated NK cells showed normal function even before starting IFN and no change was seen during IFN treatment. Clonogenic hematopoietic progenitor studies showed depression of all progenitor lines (colony-forming unit [CFU]-granulocyte, erythroid, monocyte, megakaryocyte, CFU granulocyte-macrophage, burst-forming unit-erythroid) by IFN at all dose levels except at 0.5 x 10(6) IU/m2. Considering this result and the incidence and severity of marrow depression seen at doses greater than 1.0 x 10(6) IU/m2, we would consider this the maximum dose safely tolerated if IFN alpha-2b is administered in this setting for a prolonged course on a daily basis.
 ...
PMID:Treatment with recombinant interferon (alpha-2b) early after bone marrow transplantation in patients at high risk for relapse [corrected]. 174 91

Results of sequential chromosome and cytologic studies in a patient with erythroleukemia (EL) by FAB criteria are described here. Major karyotype aberrations (MAKA) as well as normal karyotypes were detected at presentation, when the patient showed erythroid hyperplasia with moderate leftward shift of erythropoiesis and trilineage myelodysplasia, a picture suggestive of multilineage involvement. Following conventional induction therapy, the patient entered a myelodysplastic phase (MDS) with the features of refractory anemia with excess of blasts and subsequently relapsed with classical EL with maturation arrest of erythroblasts. Chromosome studies revealed a 46, XY karyotype in the MDS phase and only MAKA at leukemia relapse. These findings provide further evidence of a multistep cytogenetic and clinicopathological evolution of EL. Concomitant cytogenetic and morphologic studies in this patient seem to suggest the presence of chromosomally abnormal erythroblasts and confirm the existence of a association between MAKA and maturation arrest of erythroblasts.
 ...
PMID:Clinicopathological evolution and multilineage involvement in erythroleukemia: report of a case. 174 94

The serum concentration of erythropoietin in 79 cases with various blood diseases, uremia, chronic obstructive pulmonary disease etc was determined. At comparable degrees of anemia, patients with myelodysplastic syndrome and aplastic anemia had the highest levels of erythropoietin in our study. The high level of erythropoietin titer in patients with aplastic anemia should be taken as the nom for renal synthesis and release of this hormone. The erythropoietin level in patients with uremic anemia was lower than the level in patients with anemia of other causes but still higher than that of the normal controls. Patients suffering from polycystic kidney disease with or without uremia had a high level of erythropoietin due to local hypoxia of remnant kidney tissue resulting from the pressure of cystic formation. Different methods are used to determine the erythropoietin level, which varies with the stage and etiology of the diseases. There are other stimulating or inhibitory factors of erythropoiesis when the assay is processed. Transfusion and administration of certain drugs also influence the growth of erythroid cells, thus the serum titers of erythropoietin differed markedly between patients at comparable hemoglobin concentration.
 ...
PMID:[The difference of erythropoietin concentration in various disease]. 175 56

In an effort to overcome bone marrow failure in myelodysplastic syndrome (MDS), we have investigated recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-3 (IL-3) in phase I-II clinical trials. Although these agents partially increased peripheral blood granulocyte counts, their effect on other hematopoietic lineages was generally sporadic. Since in vitro analysis and in vivo studies in primates indicate that GM-CSF and IL-3 synergistically enhance hematopoietic stem cell proliferation, we evaluated their combined effect on marrow progenitors obtained from ten MDS patients. When used singly, each growth factor stimulated replication of granulocyte-macrophage (CFU-GM) and erythroid (BFU-E) colony-forming cells in a dose-dependent fashion. When colony-stimulating activity was compared at concentrations that maximally amplified individual MDS patients' colony numbers, IL-3 was a more potent stimulant in some patients and GM-CSF in others. When used in combination, IL-3 plus GM-CSF was more effective than each growth factor by itself in five of six patients. Our data indicate that the MDS hematopoietic progenitor stimulatory effect of these growth factors varies from patient to patient. However, the combination of GM-CSF and IL-3 appears to be more potent than the individual molecules in the majority of patients.
 ...
PMID:Granulocyte-macrophage colony-stimulating factor and interleukin-3 in combination: a potent and consistent myelodysplastic syndrome bone marrow stimulant in vitro. 175 90


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