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)

Essential thrombocythemia (ET) is an uncommon myeloproliferative disorder, which is thought to develop from a multipotent stem cell. Like other myeloproliferative diseases, ET is associated with an increased risk of development of acute leukemia (AL). However, the large majority of cases of leukemic transformation in ET are thought to be related to prior therapy, usually radioactive phosphorous or alkylating chemotherapy, and the development of AL in ET is extremely rare in the untreated patient. In this report, two cases of ET which evolved into AL without prior exposure to radiation or alkylating agents, and which were treated with long-term hydroxyurea therapy, are described. The first case had cytogenetic changes in the bone marrow suggestive of therapy-associated leukemia, and the second developed myelodysplastic syndrome on therapy which was likely chemotherapy-induced and led to acute leukemia. Prolonged used of hydroxyurea in patients with ET may lead to therapy-associated acute leukemia.
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PMID:Acute myeloid leukemia evolving from essential thrombocythemia in two patients treated with hydroxyurea. 857 54

In polycythemia vera (PV), treatment with chlorambucil and radioactive phosphorus (p32) increases the risk of leukemic transformation from 1% to 13-14%. This risk has been estimated to be 1-5.9% with hydroxyurea (HU) therapy. When compared with historical controls, the risk with use of HU does not appear to be statistically significant. The leukemogenic risk of HU therapy in essential thrombocytosis (ET) and in myelofibrosis with myeloid metaplasia (MMM) is unknown. HU remains the main myelotoxic agent in the treatment of PV, ET, and MMM. We studied 64 patients with these three disorders, seen at our institution during 1993-1995. The patients were studied for their clinical characteristics at diagnosis, therapies received, and development of myelodysplasia or acute leukemia (MDS/AL). Forty-two had PV, 15 ET, and 6 MMM, and 1 had an unclassified myeloproliferative disorder. Of the 42 patients with PV, 18 were treated with phlebotomy alone, 16 with HU alone, 2 with p32, 2 with multiple myelotoxic agents, and 2 with interferon-alpha (IFN-alpha). Two patients from the phlebotomy-treated group, one from the HU-treated group, and 1 from the multiple myelotoxic agent-treated group developed MDS/AL. In the larger group, 11 received no treatment or aspirin alone, 18 were treated with phlebotomy alone, 25 with HU, 5 with multiple myelotoxic agents, 2 with p32, 2 with IFN-alpha, and 1 with melphalan. Study of the entire group of 64 patients showed that only one additional patient (total of 5 out of 64) developed MDS/AL. This patient had been treated with HU alone. Statistical analysis did not show any association between clinical characteristics at diagnosis, or HU therapy, and development of MDS/AL (P=0.5). Thus, our data provide no evidence suggestive of increased risk of transformation to MDS/AL with HU therapy in PV, ET, and MMM. Larger, prospective studies are needed to study this issue further.
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PMID:Leukemogenic risk of hydroxyurea therapy in polycythemia vera, essential thrombocythemia, and myeloid metaplasia with myelofibrosis. 863 10

The human erythropoietin receptor (EpoR) gene has been cloned and characterized. Very few EpoR genetic abnormalities have been reported so far. Polycythemia vera (PV) is characterized by low/normal serum erythropoietin (Epo) levels with proposed Epo hypersensitivity. Myelodysplastic syndromes (MDS) are characterized by refractory anemia with variable serum Epo levels. Several reports have suggested EpoR abnormalities in both types of stem cell disorders. We analyzed DNA obtained from peripheral blood mononuclear cells of seven healthy controls, 20 patients with myeloproliferative disorders (MPD, 11 patients with PV, five agnogenic myeloid metaplasia with myelofibrosis, four essential thrombocytosis) and eight patients with refractory anemia with ringed sideroblasts (RARS), an MDS variant. The DNA was digested with four restriction enzymes (BamHI, Bgl II, Sacl and HindIII), followed by Southern blot, using a 32P radiolabeled probe, containing 1.5 kb of the human EpoR cDNA. All 20 MPD patients and seven out of the eight MDS patients demonstrated a restriction pattern which was identical to the seven normal controls, as well as to the erythroid cell line K562, and also consistent with the expected restriction map, for all four enzymes tested. One RARS patient had a normal pattern with three enzymes but a different one with HindIII. The HindIII 12 kb large band was replaced by a faint 12 kb band and a new (about 9 kb) band appeared. The EpoR restriction map and the normal pattern obtained with the other three enzymes suggest that this patient has a 3 kb upstream deletion in one allelic EpoR gene. The same molecular pattern was detected in the patient's sister, who suffers from anemia with mild bone marrow (BM) dyserythropoiesis and plasmacytosis. Northern blot analysis showed that the patient's BM RNA carried normal EpoR message. This familial pattern may represent polymorphism. However, the patient's very high serum Epo level, her resistance to treatment with recombinant Epo, and the abnormally low growth rate of in vitro erythroid cultures, suggesting poor response to Epo in this MDS patient as well as the hematological abnormalities in her sister, support the speculation that the different EpoR gene might serve as a genetic predisposing marker and potentially could be involved (probably via post-transcriptional mechanisms and by an interaction with other factors or cytokines) in the pathogenesis. Our data suggest that the EpoR is intact in MPD and in most patients with RARS. One RARS patient had a familial different genetic structure, which could represent polymorphism. However, we can speculate also that it might be involved in the pathogenesis of the disease.
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PMID:Analysis of the erythropoietin receptor gene in patients with myeloproliferative and myelodysplastic syndromes. 870 17

Procoagulant activity (PCA) of peripheral mononuclear cells (PMC) was evaluated in patients with primary thrombocythemia (PT, group A), polycythemia vera (PV), idiopathic myelofibrosis (IM) and myelodysplastic syndromes (group B), and in 15 healthy subjects as control group. PCA of PMC was assayed under basal conditions and after agonist-induced stimulation: bacterial lipopolysaccharide, glycosylated granulocyte-macrophage colony-stimulating factor, recombinant alpha-interferon. PCA was similar in the control group and group A when no stimulation was used, while PCA was found significantly higher in group B patients in the same conditions. In group A patients and in the control group, but not in group B patients, a lower PCA expression was found when PMC were simultaneously coincubated with LPS and alpha-interferon with respect to LPS incubation alone.
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PMID:Procoagulant activity of mononuclear cells is increased in myeloproliferative and myelodysplastic diseases. 873 90

Two cases of XYY male with refractory anemia with excess of blasts are reported, and previous reported XYY males with hematologic malignancy are reviewed. Altogether 26 cases were collected for analysis: acute myeloid leukemia (10), acute lymphocytic leukemia (seven), acute leukemia (two), chronic myelocytic leukemia (three), myelodysplastic syndrome (three), and essential thrombocythemia (one). The age at the time of diagnosis ranged in age from 7.5 to 81 years. In three of six XYY/XY mosaicism cases, XYY clone was associated with malignancy. However, in two cases XYY clone was not involved. The evidence presented here suggests that the event of an XYY male with hematologic malignancy is incidental rather than a genetic etiology.
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PMID:XYY male and hematologic malignancy. 883 Jul 31

A 46-year-old man with Werner's syndrome was admitted with epigastralgia and body weight loss. The peripheral blood findings showed anemia, thrombocytosis and eosinophilia. Bone marrow aspiration and biopsy revealed increases in eosinophils and megakaryocytes, myelodysplastic change with 6.6% myeloblast, and myelofibrosis. Chromosomal analysis revealed 46, XY, +der(1;7), -7, del(20). He was diagnosed as having myelodysplastic syndrome with myelofibrosis or essential thrombocythemia. Three months later, pancytopenia appeared with a relative increase of blasts positive for CD41 and negative for myeloperoxidase. He died of respiratory failure due to pneumonia. An autopsy revealed severe myelofibrosis with proliferation of megakaryocytes and blasts. A final diagnosis of acute megakaryoblastic leukemia was made. Werner's syndrome is rare, and it is even more unusual to have the complication of acute leukemia with der (1;7) seen in this case.
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PMID:[Werner's syndrome developing acute megakaryoblastic leukemia with der(1;7)]. 902 58

The telomerase activity of various hematologic disorders, including malignant and non-malignant ones is discussed in this paper. In total of 137 cases, each positivity of telomerase activity was MDS = 17/51, overt leukemia from MDS = 6/15, AML = 17/21, ALL = 4/6, CML-CP (chronic phase) = 0/10, CML-BC (blastic crisis) = 4/4, MPD (myeloproliferative disease)-BC = 3/3, CLL = 1/10, MM (multiple myeloma) = 0/6, aplastic anemia = 3/5, essential thrombocytosis = 0/3, and polycythemia vera = 1/3. The MPD-BC showed very high level of telomerase activity as well as CML-BC cases. From the analysis for 18 cases of AML and/or malignant lymphoma patients, significant results showed that the expression of cyclin D/E was not related to telomerase activity in these hematologic disease, as was not the case with breast cancer which was reported formerly.
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PMID:[Analysis for telomerase activity in various hematologic disorders]. 961 44

Cyclin A is a cell cycle regulatory protein that functions in mitotic and S phase control in mammalian cells. However, in contrast to other G1 phase regulatory proteins, such as cyclin D, retinoblastoma protein and p16INK4A, cyclin A seems not to be commonly involved in tumorigenesis. Recently, a second human cyclin A--cyclin A1--has been identified. In contrast to cyclin A which is expressed throughout embryonic development and in adult tissue, the expression of cyclin A1 has been reported to be restricted to embryonic and germ line cells. We have confirmed the absence of cyclin A1 mRNA from normal peripheral blood leukocytes of seven healthy donors by single step reverse transcriptase-polymerase chain reaction (RT-PCR). Furthermore, we have examined the expression of cyclin A1 mRNA in 173 peripheral blood samples of 162 patients with various hematological malignancies. Cyclin A1 mRNA was detectable in 11 of 11 patients with acute myeloid leukemia, three of three patients with acute biphenotypic leukemia, eight of eight patients with myelodysplastic syndrome, 59 of 69 patients with chronic myelogenous leukemia (CML) at diagnosis, 13 of 15 patients with CML in blastic transformation, 10 of 18 patients with chronic lymphocytic leukemia, two of nine patients with essential thrombocythemia, and only two of 10 patients with acute lymphoblastic leukemia (ALL) with both cyclin A1 RT-PCR positive ALL leukemias being undifferentiated relapses. In addition, cyclin A1 mRNA was found in one of six leukapheresis products, harvested from individuals without hematological disorders. Taken together, cyclin A1 is expressed in the majority of myeloid and undifferentiated hematological malignancies as well as in normal hematopoietic progenitor cells. We conclude that cyclin A1, a protein potentially involved in G1/S phase progression of immature cells, might be necessary for proliferation of early hematopoietic progenitor cells and their leukemic counterparts being blocked at that stage of differentiation.
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PMID:Cyclin A1 is predominantly expressed in hematological malignancies with myeloid differentiation. 963 17

This paper reports on an analysis of nearly 27,000 hematological malignancies diagnosed in the U.K. in the 10-year period 1984 to 1993. The unique observations provided in this analysis are the similarity of the sex-specific curves by age for acute myeloid leukemia, myelodysplasia types, polycythemia rubra vera, and myelofibrosis (or myelosclerosis). The unusual age-sex-specific distribution of essential thrombocythemia, suggesting a unique epidemiology, has never been reported before. The unusual female excess of the nodular sclerosing adolescent peak in Hodgkin's disease and its rapid fall with time is potentially of great importance. An even younger childhood peak of acute lymphoblastic leukemia is presented. Overall these data represent the most reliable available in the U.K., being population based, specially collected and will form the basis of considerable further investigations.
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PMID:Age and sex distributions of hematological malignancies in the U.K. 972 89

Two main types of therapy-related acute myeloid leukemias (tAML) and myelodysplastic syndromes (tMDS) have been described. The first classical type typically occurs late after use of alkylating agents and presents as MDS with -7/del 7q and/or -5/del5q. The second form occurs early after the use of agents targeted at topoisomerase II, and presents as AML with 11q23 or other rearrangements of de novo AML. Recently, we and others reported, in AML and MDS, a strong correlation between cytogenetic rearrangements leading to 17p deletion, a specific type of dysgranulopoiesis and p53 mutation; several of those cases of 17p- syndrome were therapy-related. Over the last 15 years, we observed 25 cases of tAML and tMDS with 17p deletion, which represented 36% of the AML and MDS with 17p deletion diagnosed during that period. Median age was 59 years. Twenty-one patients had tMDS and four tAML. Typical dysgranulopoiesis and p53 mutation and/or overexpression were seen in 22 of 24 and 16 of 19 evaluable patients, respectively. 17p deletion resulted from unbalanced translocations involving 17p (18 cases), monosomy 17 (five cases), i(17q) (one case) or del 17p (one case). Twenty-one patients also had -5/del 5q, and/or -7/del 7q. Median interval from treatment of the first tumor of tAML and tMDS was 94 months (range 19-252). Median survival was only 7 months. Based on primary tumor and antineoplastic agents used, patients could be relatively well divided into two groups: a first group of 11 cases, occurring mainly after a lymphoid neoplasm (eight cases) treated by chemotherapy with an alkylating agent (10 cases), and a second group of 14 cases occurring after essential thrombocythemia (ET) or polycythemia vera (PV) treated mainly by hydroxyurea (10 cases), pipobroman (eight cases), 32P (six cases) but rarely by alkylating agents (two cases). -7/del 7q was found in 10 of the 11 patients in the first group, as compared to three of the 14 patients of the second group (P = 0.0001). Therefore, therapy-related cases represent a high proportion of AML and MDS with the 17p- syndrome. They have many features in common with classical tMDS and tAML, including long interval from the first tumor, a usual preleukemic phase, and frequent occurrence of -5/del 5q. About one half of them, in addition, occur after alkylating agents and generally carry -7/del 7q. The other half, however, occur mainly after ET or PV treated by hydroxyurea or other non-alkylating agents, and usually have no -7/del 7q. These findings bring further support to a possible relationship between prior drugs used and cytogenetic rearrangements in tAML and tMDS.
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PMID:Therapy-related myelodysplastic syndrome and acute myeloid leukemia with 17p deletion. A report on 25 cases. 1002 99


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