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)

Loss of chromosome 7 (-7) or deletion of its long arm (7q-) are recurring chromosome abnormalities in myeloid disorders, especially in therapy-related myelodysplastic syndrome (t-MDS) and acute myeloid leukemia (t-AML). The association of -7/7q- with myeloid leukemia suggests that these regions contain a novel tumor suppressor gene(s) whose loss of function contributes to leukemic transformation or tumor progression. Based on chromosome banding analysis, two critical regions have been identified: one in band 7q22 and a second in bands 7q32-q35. We analyzed bone marrow and blood samples from 21 patients with myeloid leukemia (chronic myeloid leukemia, n = 2; de novo MDS, n = 4; de novo AML, n = 13; t-AML, n = 2) that on chromosome banding analysis exhibited deletions (n = 19) or reciprocal translocations (n = 2) of band 7q22 using fluorescence in situ hybridization. As probes, we used Alu-polymerase chain reaction products from 22 yeast artificial chromosome (YAC) clones that span chromosome bands 7q21.1-q32, including representative clones from a panel of YACs recognizing a contiguous genomic DNA fragment of 5 to 6 Mb in band 7q22. In the 19 cases with deletions, we identified two distinct commonly deleted regions: one region within band 7q22 was defined by the two CML cases; the second region encompassed a distal part of band 7q22 and the entire band 7q31 and was defined by the MDS/AML cases. The breakpoint of one of the reciprocal translocations was mapped to 7q21.3, which is centromeric to both of the commonly deleted regions. The breakpoint of the second translocation, which was present in unstimulated bone marrow and phytohemagglutinin-stimulated blood of an MDS patient, was localized to a 400-kb genomic segment in 7q22 within the deletion cluster of the MDS/AML cases. In conclusion, our data show marked heterogeneity of 7q22 deletion and translocation breakpoints in myeloid leukemias, suggesting the existence of more than one pathogenetically relevant gene.
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PMID:Molecular cytogenetic delineation of deletions and translocations involving chromosome band 7q22 in myeloid leukemias. 905 25

Three consecutive cases of pediatric myelodysplastic syndrome (MDS) diagnosed over a three-year period in Queen Mary Hospital, Hong Kong, were described. Depending on the classification system used, they comprised two cases of chronic myelomonocytic leukemia (CMMoL) of which one can be reclassified as juvenile chronic myeloid leukemia (JCML) and one cases of refractory anemia with excess of blasts (RAEB) or an alternative diagnosis of atypical CML. Cytogenetic abnormalities were detected in all of them on examination of bone marrow cells. Of the two CMMoL, one had monosomy 21, whereas the other had hypodiploidy. The patient with RAEB had a complex karyotype of 46,X,del(X)(q24),t(1;7) (p22;q32),add(15)(q26)(8). The balanced translocation (1;7) seen in this patient was exceedingly rare and, to the best of our knowledge, was reported only twice in the literature. The karyotypic abnormalities that we saw in our patients were not well recognized in pediatric MDS. This report emphasizes the importance of cytogenetic study in children suspected of suffering from MDS, which remains a rare disorder of childhood, and a need to rationalize current classification schemes.
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PMID:Cytogenetic abnormalities in pediatric myelodysplastic syndrome: a report of three cases. 907 4

A 40-year-old male with Ph-positive CML underwent PBSC autografting after initial treatment with hydroxyurea and interferon. Following autograft he remained in chronic phase with cytogenetic or molecular evidence of low levels of residual Ph-positive cells. However, additional cytogenetic abnormalities, including t(3;21) typically seen in therapy-related myelodysplastic syndrome (MDS) and AML and blast crisis of CML, developed as an independent cell line following the autograft. More than 4 years after the autograft, the patient remains in chronic phase with no evidence of accelerated phase or blast crisis of CML, but with a concurrent MDS. We report a case of CML who developed therapy-related MDS following PBSC autograft while still remaining in chronic phase.
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PMID:t(3;21) following peripheral blood stem cell transplantation in chronic phase chronic myeloid leukaemia. 920 22

We analyzed the expression of the Thy-1 antigen (CD90) in CD34+ acute leukemia using two-color flow cytometry. Leukemic cells were obtained from the bone marrow (BM) and/or the peripheral blood (PB) of 57 patients: 37 with acute myelogenous leukemia (AML) including nine with secondary AML following myelodysplastic syndrome (MDS/AML), and 20 with acute lymphoblastic leukemia (ALL) including three with chronic myelogenous leukemia in blast crisis (CML-BC) of the lymphoid type. Among these patients, one (3.6%) with de novo AML, two (22.2%) with MDS/AML, three (17.6%) with de novo ALL, and two (66.7%) with CML-BC coexpressed CD34 and Thy-1 (CD34+ Thy-1+) on more than 20% of the mononuclear cells within 'lymph' plus 'blast' window. Thy-1 was rarely expressed in de novo acute leukemia especially in AML. Interestingly, in 1 patient with CML-BC, the leukemic cells in BM were divided into two subpopulations (CD34+ Thy-1low and CD34+ Thy-1high), whereas most of the CD34+ leukemic cells in PB were Thy-1high. However, the mechanism for the mobilization of CD34+ Thy-1high leukemic cells into the PB is unknown.
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PMID:Flow cytometric analysis of Thy-1 expression in CD34-positive acute leukemia. 940 Dec 77

The immune reactivity of allogeneic lymphocytes plays a major role in control of leukemia after bone marrow transplantation. We studies the efficacy of donor leukocyte transfusion (DLT) on acute and chronic leukemia in relapse after bone marrow transplantation in Japan. Sixty nine patients with chronic myelocytic leukemia (N = 17), acute lymphoblastic leukemia (N = 25), acute myelocytic leukemia (N = 26), myelodysplastic syndrome (N = 5), non-Hodgkin lymphoma (N = 2) and rhabdomyosarcoma (N = 1) were treated with transfusions of donor lymphocytes. Therapeutic effects were induced by donor leukocyte transfusion in 20 patients (29%) including 3 patients out of 4 (75%) with CML in cytogenetic and chronic phase relapse, 4 out of 5 (80%) patients with myelodysplastic syndrome, 3 out of 13 (23%) patients with CML in transformed phase, 5 out of 25 (20%) patients with acute myelocytic leukemia, and 4 out of 20 (20%) patients with acute lymphoblasic leukemia. Twenty two patients (30%) developed acute GVHD (> or = 2) and 6 out of 73 (8.2%) patients developed fatal GVHD after donor leukocyte transfusion. Patients relapsed within 6 months after marrow transplantation had a probability of having severe acute GVHD (> or = 2) after DLT. Fourteen out of 24 (58%) patients with GVL response were re-relapsed thereafter. Minimal dose of donor leukocytes infused in successfully treated 9 patients without cytoreductive therapy was 2 x 10(7)/kg in total and minimal dose of that in 6 patients with fatal GVHD was 7 x 10(7)/kg in total. The anti-leukemia effect of donor leukocyte transfusion was strongest against CML in cytogenetic and chronic phase and induce a durable complete remission.
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PMID:[Therapeutic effect of donor leukocyte transfusion in relapsing marrow transplants in Japan]. 942 32

Juvenile myelomonocytic leukemia (JMML) is a rare myeloproliferative disease of early childhood, that is peculiarly characterized by the ability of bone marrow progenitors to spontaneously proliferate in vitro, giving rise to granulocyte-macrophage colonies. Although the genetic alteration/s leading to JMML development are still unclear, several lines of evidence indicate that the JMML initiating cell (JMML-IC) may belong to the pool of early stem-like hematopoietic progenitors. Increased EVI-1 gene expression has been detected in a number of myeloproliferative disorders including MDS, AML, blast crisis of CML, and more recently in the peripheral blood of some JMML patients. In order to investigate the nature of the cells expressing EVI-1 in JMML patients, we analyzed its expression in CFU-GM obtained from bone marrow and peripheral blood as well as from highly purified CD34+ progenitors. Normal CFU-GM obtained both from bone marrow mononuclear cells and from highly purified CD34+ cells were also analyzed. Overall, our results suggest that the EVI-1 gene may be normally expressed in early hematopoietic progenitor cells and that in JMML patients an expansion of the EVI-1 positive cell population can be revealed within the clonogenic progenitor pool.
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PMID:EVI-1 gene expression in myeloid clonogenic cells from juvenile myelomonocytic leukemia (JMML). 944 18

To clarify whether regulatory cytokines inhibit hematopoiesis in patients with myelodysplastic syndromes (MDS), malignancies characterized by the formation of cytopenias despite the presence of cellular bone marrow, expression of TNF-alpha and IFN-gamma by bone marrow cells was investigated using specific reverse transcriptase-polymerase chain reaction assays. An enhanced expression of the mRNA for TNF-alpha was observed in most of the samples from MDS patients (11/14, 79%), whereas no enhancement was observed in bone marrow samples from AML (0/6), CML (0/2) or control cases (0/8). The expression of IFN-gamma was also enhanced in some of MDS cases (5/12, 42%) while AML (0/5), CML (0/2) and control cases (0/6) showed very low levels of IFN-gamma mRNA expression. Immunohistochemical examination confirmed the scattered presence of TNF-alpha or IFN-gamma producing cells in the bone marrow of MDS patients. The majority of these cells were CD68-positive macrophage lineage cells. These results suggested that disruption of hematopoiesis in MDS might be caused by enhanced production of inhibitory regulatory cytokines especially TNF-alpha and occasionally IFN-gamma by bone marrow macrophages.
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PMID:Overexpression of tumor necrosis factor (TNF)-alpha and interferon (IFN)-gamma by bone marrow cells from patients with myelodysplastic syndromes. 944 19

Cytogenetic analysis was performed in 86 cases of hematologic malignancy, using conventional cytogenetic analysis and fluorescence in situ hybridization (FISH) analysis at two university hospitals in Korea between 1993 and 1995. In addition to well-known anomalies, some unusual abnormalities were found, such as t(17;22), trisomy 9 combined with t(14;17), (2;7) and Philadelphia chromosome in CML; t(1;12), t(11;22), t(9;17), and t(12;21) in AML; trisomy 11 in MDS; t(2;9) and complex t(8;8;13;14) in ALL. The results of FISH analysis in interphase nuclei using a translocation probe for CML and APL showed more than 85% positive cells in CML, and 75% positive cells in APL.
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PMID:Cytogenetic and fluorescence in situ hybridization analyses of hematologic malignancies in Korea. 946 Apr 92

To explore the feasibility and potential advantages of PBSC in allogeneic transplantation, we grafted 24 patients (age 16-57, median 37) with different hematologic diseases (ALL = 10, AML = 5, MM = 4, NHL = 2, CML = 1, MDS = 1, AA = 1), 23 HLA-identical to their siblings and 1 partially matched. Cells were collected from donors by apheresis after G-CSF 10 to 16 mg/kg/day for 4 to 5 days, and stored at 4 degrees C until infusion. The patients were conditioned with chemotherapy regimens including busulfan and cyclophosphamide in the majority of cases and received GVHD prophylaxis with CSA-MTX in all but two. The graft consisted of PBSC alone, with a median of 143.5 (range 18.1-358.9) x 10(4)/kg CFU-GM, 9.0 (range 3.3-18.0) x 10(6)/kg CD34+ cells and 2.8 (range 1.2 to 8.6) x 10(8)/kg CD3+ and cells. An ANC >0.0.5 x 10(9)/L was recovered on (median) day 13 (range 11-17), and a platelet count >50 x 10(9)/L on (median) day 13 (range 12-55) post graft. There was no correlation between CD34+ cells or CFU-GM number in the inoculum and time to hematologic reconstitution. Acute GVHD (grade II-IV) occurred in 10 out of 22 (45%), chronic GVHD in 10 out of 18 evaluable (55%) patients. We found no relationship between occurrence of acute or chronic GVHD and number of CD3+ cells in the graft. Four patients relapsed and 7 died after transplantation. Fifteen patients are currently alive and disease-free 67 to 710 (median 286) days from the graft. Allogeneic transplantation with unmanipulated PBSC ensures a fast and stable engraftment. Acute GVHD incidence and severity seems comparable to that of bone marrow transplantation, but there may be an increase in chronic GVHD, mainly of the extensive form.
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PMID:Transplantation of unmanipulated allogeneic PBSC: preliminary report on 24 patients. 957 Jun 80

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


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