13 results on '"Dewald G"'
Search Results
2. JAK2 V617F is a rare finding in de novo acute myeloid leukemia, but STAT3 activation is common and remains unexplained.
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Steensma, D. P., McClure, R. F., Karp, J. E., Tefferi, A., Lasho, T. L., Powell, H. L., DeWald, G. W., and Kaufmann, S. H.
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PROTEIN-tyrosine kinases ,GENETIC mutation ,HEMATOPOIETIC growth factors ,MYELOID leukemia ,MYELOPROLIFERATIVE neoplasms ,BONE marrow diseases - Abstract
Signal transducer and activator of transcription (STAT) proteins are phosphorylated and activated by Janus kinases (JAKs). Recently, several groups identified a recurrent somatic point mutation constitutively activating the hematopoietic growth factor receptor-associated JAK2 tyrosine kinase in diverse chronic myeloid disorders - most commonly classic myeloproliferative disorders (MPD), especially polycythemia vera. We hypothesized that the JAK2 V617F mutation might also be present in samples from patients with acute myeloid leukemia (AML), especially erythroleukemia (AML-M6) or megakaryoblastic leukemia (AML-M7), where it might mimic erythropoietin or thrombopoietin signaling. First, we documented STAT3 activation by immunoblotting in AML-M6 and other AML subtypes. Immunoperoxidase staining confirmed phosphorylated STAT3 in malignant myeloblasts (21% of cases, including all AML-M3 samples tested). We then analyzed genomic DNA from 162 AML, 30 B-cell lymphoma, and 10 chronic lymphocytic leukemia (CLL) samples for JAK2 mutations, and assayed a subset for SOCS1 and FLT3 mutations. Janus kinase2 V617F was present in 13/162 AML samples (8%): 10/13 transformed MPD, and three apparent de novo AML (one of 12 AML-M6, one of 24 AML-M7, and one AML-M2 - all mixed clonality). FLT3 mutations were present in 5/32 (16%), while SOCS1 mutations were totally absent. Lymphoproliferative disorder samples were both JAK2 and SOCS1 wild type. Thus, while JAK2 V617F is uncommon in de novo AML and probably does not occur in lymphoid malignancy, unexplained STAT3 activation is common in AML. Janus kinase2 extrinsic regulators and other proteins in the JAK-STAT pathway should be interrogated to explain frequent STAT activation in AML. [ABSTRACT FROM AUTHOR]
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- 2006
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3. WHO-defined chronic neutrophilic leukemia: a long-term analysis of 12 cases and a critical review of the literature.
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Elliott, M. A., Hanson, C. A., Dewald, G. W., Smoley, S. A., Lasho, T. L., and Tefferi, A.
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LETTERS to the editor ,LEUKEMIA - Abstract
Presents a letter to the editor about chronic neutrophilic leukemia, as defined by the WHO.
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- 2005
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4. Low expression of the myeloid differentiation antigen CD65s, a feature of poorly differentiated AML in older adults: study of 711 patients enrolled in ECOG trials.
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Paietta, E, Neuberg, D, Bennett, J M, Dewald, G, Rowe, J M, Cassileth, P A, Cripe, L, Tallman, M S, and Wiernik, P H
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MYELOID leukemia ,CD antigens ,CYTOGENETICS ,GENE expression - Abstract
CD65s appears when the progenitor antigen CD34 disappears, suggesting that this sialylated carbohydrate antigen marks a turning point in normal myeloid differentiation. We characterized acute myeloid leukemia (AML) with low CD65s expression (CD65s[SUPlow] AML) in 711 patients entered on seven Eastern Cooperative Oncology Group AML treatment trials (1986-1999). Of those, 198 (28%) qualified as having CD65s[SUPlow] AML. Morphologically, CD65s[SUPlow] AML was more common in FAB subgroups with minimal differentiation, M0/M1 (P = <0.0001). Early precursor antigens CD34, CD117 and terminal transferase were more frequent in CD65s[SUPlow] than CD65s[SUPhigh] AML (P = < 0.0001). Myeloperoxidase was present in fewer CD65s[SUPlow] myeloblasts, and the more mature myeloid antigens, CD15 and CD11b, were rarely detected (P = < 0.0001). Yet, the two diagnoses did not differ in the distribution of cytogenetic prognostic groups or the occurrence of the multidrug-resistance mediator, P-glycoprotein. CD65s[SUPlow] AML patients were significantly older than CD65s[SUPhigh] cases (P < 0.0001). Furthermore, the incidence of CD65s[SUPlow] cases increased with age, from 20% in patients under the age of 50 years to 67% in patients older than 80 years (P < 0.0001). Overall, complete remission (CR) rate and overall survival were comparable in CD65s[SUPlow] and CD65s[SUPhigh]AML. However, among patients 455 years of age, CD65s[SUPlow] AML had a decreased CR rate of 33 vs 44% in CD65s[SUPhigh] AML (P = 0.055). Thus, CD65s[SUPlow] AML represents immunophenotypically undifferentiated disease and occurs predominantly in older adults. Although not statistically significant, the observed association between low CD65s expression and decreased CR rate only in patients over the age of 55 is intriguing. [ABSTRACT FROM AUTHOR]
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- 2003
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5. Secondary myelodysplastic syndrome and acute myelogenous leukemia are significant complications following autologous stem cell transplantation for lymphoma.
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Howe, R, Micallef, I N M, Inwards, D J, Ansell, S M, Dewald, G W, Dispenzieri, A, Gastineau, D A, Gertz, M A, Geyer, S M, Hanson, C A, Lacy, M Q, Tefferi, A, and Litzow, M R
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MYELODYSPLASTIC syndromes ,SYNDROMES ,MYELOID leukemia ,AUTOTRANSPLANTATION ,STEM cell transplantation - Abstract
Summary:Secondary myelodysplastic syndrome (sMDS) and acute myelogenous leukemia (AML) have been recognized with increasing frequency following autologous stem cell transplantation (ASCT). A retrospective analysis of 230 consecutive patients with Hodgkin's lymphoma (HL, 64) and non-Hodgkin's lymphoma (NHL, 166) who underwent ASCT was conducted to assess the incidence and risk factors for the development of sMDS/AML. At a median follow up of 41 months (range 0.1-177 months), 10 of 230 patients (4.3%) developed sMDS/AML. The 5-year-actuarial incidence of sMDS/AML was 13.1% and 5-year cumulative incidence by competing risk analysis was 4.2%. The median time to development of sMDS/AML was 39.9 months from the time of ASCT (range 12.1-62.0 months). Complex karyotypes at diagnosis of sMDS/AML included structural anomalies and/or loss of chromosome 5 (eight patients), 7 (five patients), 17 (two patients) and 20 (two patients). All patients subsequently died, at a median of 6.8 months (range 0-39.9) from diagnosis of sMDS/AML. Fluorescent in situ hybridization (FISH) analysis for -5/5q- and -7/7q- were normal in all six patients whose pre-ASCT bone marrow was available for testing. Five of the six had samples available for testing at diagnosis of sMDS/AML and all had abnormal FISH results. By univariate statistical analysis, male gender (P=0.01), prior alkylating agents (mechlorethamine for HL, P=0.001 and cyclophosphamide for NHL, P=0.05) and the number of prior treatment regimens (P=0.04) were significantly associated with the development of sMDS/AML. Given the relatively low incidence rate of sMDS/AML, these analyses are primarily exploratory in nature but provide some insight into relevant risk factors and illustrate the risk of developing sMDS/AML after myeloablative conditioning and ASCT for lymphoma.Bone Marrow Transplantation (2003) 32, 317-324. doi:10.1038/sj.bmt.1704124 [ABSTRACT FROM AUTHOR]
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- 2003
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6. Chromosome abnormalities clustering and its implications for pathogenesis and prognosis in myeloma.
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Debes-Marun, C S, Dewald, G W, Bryant, S, Picken, E, Santana-Dávila, R, González-Paz, N, Winkler, J M, Kyle, R A, Gertz, M A, Witzig, T E, Dispenzieri, A, Lacy, M Q, Rajkumar, S V, Lust, J A, Greipp, P R, and Fonseca, R
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CHROMOSOME abnormalities , *KARYOTYPES , *LEUKEMIA - Abstract
The nonrandom recurrent nature of chromosome abnormalities in myeloma suggests a role for them in disease pathogenesis. We performed a careful cytogenetic analysis of patients with abnormal karyotypes (n = 254), to discern patterns of association, search for novel abnormalities and elucidate clinical implications. Patients with karyotypic abnormalities suggestive of myelodysplasia/acute leukemia were excluded. In this study we compared survival by abnormality only between patients with abnormal karyotypes. Patients with abnormalities were more likely to have features of aggressive disease as compared to all other patients without abnormalities entered into the myeloma database (lower hemoglobin, higher β[sub 2]-microglobulin, labeling-index and plasmocytosis; all P < 0.0001). Several groups of patients could be readily identified; hypodiploid (22%), pseudodiploid (36%), hyperdiploid (31%) and near-tetraploid (11%). Clustering associations were seen among several trisomies and monosomy of chromosome 13 and 14. Several monosomies (-2, -3, -13, -14 and -19), 1p translocations/ deletions, and hypodiploidy were associated with a significantly shorter survival. Trisomy of chromosome 13 was rare (<2%). Even among patients with abnormal karyotypes, specific chromosome abnormalities can impart biologic variability in myeloma, including several monosomies, hypodiploidy and abnormalities of 1 p. [ABSTRACT FROM AUTHOR]
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- 2003
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7. B-CLL cells are capable of synthesis and secretion of both pro- and anti-angiogenic molecules.
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Kay, N E, Bone, N D, Tschumper, R C, Howell, K H, Geyer, S M, Dewald, G W, Hanson, C A, and Jelinek, D F
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CHRONIC lymphocytic leukemia ,B cells ,CELL metabolism ,PROTEIN analysis ,RNA metabolism ,PEPTIDE analysis ,GLYCOPROTEIN analysis ,ANTIGENS ,CELL physiology ,CELL receptors ,CELLS ,COLLAGEN ,COMPARATIVE studies ,GLYCOPROTEINS ,GROWTH factors ,LONGITUDINAL method ,LYMPHOKINES ,RESEARCH methodology ,MEDICAL cooperation ,GENETIC mutation ,NEOVASCULARIZATION inhibitors ,PEPTIDES ,PROTEINS ,RESEARCH ,TRANSFERASES ,EVALUATION research ,VASCULAR endothelial growth factors ,ENDOTHELIAL growth factors ,CANCER cell culture - Abstract
Initial work has shown that clonal B cells from B-chronic lymphocytic leukemia (B-CLL) are able to synthesize pro-angiogenic molecules. In this study, our goal was to study the spectrum of angiogenic factors and receptors expressed in the CLL B cell. We used ELISA assays to determine the levels of basic fibroblast growth factors (bFGF), vascular endothelial growth factor (VEGF), endostatin, interferon-alpha (IFN-alpha) and thrombospondin-1 (TSP-1) secreted into culture medium by purified CLL B cells. These data demonstrated that CLL B cells spontaneously secrete a variety of pro- and anti-angiogenic factors, including bFGF (23.9 pg/ml +/- 7.9; mean +/- s.e.m.), VEGF (12.5 pg/ml +/- 2.3) and TSP-1 (1.9 ng/ml +/- 0.3). Out of these three factors, CLL B cells consistently secreted bFGF and TSP-1, while VEGF was expressed in approximately two-thirds of CLL patients. Of interest, hypoxic conditions dramatically upregulated VEGF expression at both the mRNA and protein levels. We also employed ribonuclease protection assays to assay CLL B cell expression of a variety of other angiogenesis-related molecules. These analyses revealed that CLL B cells consistently express mRNA for VEGF receptor 1 (VEGFR1), thrombin receptor, endoglin, and angiopoietin. Further analysis of VEGFR expression by RT-PCR revealed that CLL B cells expressed both VEGFR1 mRNA and VEGFR2 mRNA. In summary, these data collectively indicate that CLL B cells express both pro- and anti-angiogenic molecules and several vascular factor receptors. Because of the co-expression of angiogenic molecules and receptors for some of these molecules, these data suggest that the biology of the leukemic cells may also be directly impacted by angiogenic factors as a result of autocrine pathways of stimulation. [ABSTRACT FROM AUTHOR]
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- 2002
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8. Agnogenic myeloid metaplasia associated with Klinefelter syndrome: a case report.
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Kumar, S., Menke, D. M., Dewald, G. W., and Colon-Otero, G.
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KLINEFELTER'S syndrome ,ACUTE leukemia ,SEX chromosomes ,MYELOPROLIFERATIVE neoplasms ,MYELOID metaplasia ,TUMORS - Abstract
Klinefelter syndrome is the most commonly diagnosed sex chromosome disorder among males. It is usually associated with 47 chromosomes, including two Xs and one Y. The formal cytogenetic designation for Klinefelter syndrome is 47, XXY; the extra sex chromosome is due to meiotic chromosomal nondisjunction. Increased risk of various malignant diseases has been recognized among patients with different congenital chromosomal abnormalities. Since the early 1960s, numerous reports have appeared of an increased risk of malignant neoplasms among patients with Klinefelter syndrome. Evidence suggests a correlation with increased incidences of germ cell tumors and breast cancers. Whether these patients are at an increased risk of hematologic malignant disease, especially acute leukemia, is still uncertain. This report describes a patient with agnogenic myeloid metaplasia and Klinefelter syndrome, an association not previously reported. [ABSTRACT FROM AUTHOR]
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- 2002
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9. Deletions of chromosome 13 in multiple myeloma identified by interphase FISH usually denote large deletions of the q arm or monosomy.
- Author
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Fonseca, R, Oken, M M, Harrington, D, Bailey, R J, Van Wier, S A, Henderson, K J, Kay, N E, Van Ness, B, Greipp, P R, and Dewald, G W
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MULTIPLE myeloma ,CHROMOSOME abnormalities ,MONOCLONAL gammopathies - Abstract
Deletions of the long arm of chromosome 13 (13q-) are observed in patients with multiple myeloma (MM), are rarely observed in the monoclonal gammopathy of undetermined significance (MGUS) and have been associated with a worsened prognosis in MM. However, no minimally deleted region in the 13q arm has been defined at 13q, and consequently no tumor suppressor genes have yet been identified that are important for disease pathogenesis. We attempted to characterize these chromosome 13q deletions at the molecular cytogenetic level. We studied 351 newly diagnosed patients, entered into the E9486/E9487 clinical study of the Eastern Cooperative Oncology Group. Fluorescent in situ hybridization (FISH) combined with immune fluorescent detection (cIg-FISH) of clonal plasma cells (PC) and cytomorphology were used to analyze interphase, bone marrow (BM) cell, cytospin slides. We simultaneously used DNA probes for the following locus specific probes (LSI); LSI 13 (Rb) and D13S319, which hybridize to 13q14. We subsequently studied distal deletions using the D13S25 probe (13q14.3) and a subtelomeric probe (13qSTP) for the 13q-arm (D13S327) in 40 cases with documented LSI 13 (Rb)/D13S319 deletion and 40 without deletion of these loci. Of 325 evaluable patients, we found 13q deletions in 176 (54%) using LSI 13 (Rb) and D13S319 probes. Of 40 patients with LSI 13 (Rb)/D13S319 deletions, 34 (85%) had coexistent deletion of both D13S25/13qSTP. These results indicate that chromosome 13 deletions in MM involve loss of most if not all of the 13q arm perhaps even indicating monosomy. In six cases the 13qSTP signal was conserved, but D13S25 was lost indicating large interstitial deletions involving 13q14. In 39 of the 40 cases without LSI 13 (Rb)/D13S319 deletions, the normal pattern of two pairs of signals was observed for D13S25/13qSTP. Deletions involving 13q14 are very common in MM as detected by cIg-FISH. These deletions appear to predominantly involve loss of large segments of the 13q arm or monosomy 13, and only occasionally represent an interstitial deletion. [ABSTRACT FROM AUTHOR]
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- 2001
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10. Chronic neutrophilic leukemia (CNL): a clinical, pathologic and cytogenetic study.
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Elliott, M A, Dewald, G W, Tefferi, A, and Hanson, C A
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MYELOPROLIFERATIVE neoplasms , *LEUKEMIA - Abstract
This report describes a single institution's recent experience with six patients fulfilling the diagnostic criteria of chronic neutrophilic leukemia. No patient had the Philadelphia chromosome or the BCR/ABL fusion gene. None of the common cytogenetic abnormalities characteristic of myeloid disorders were detected. Two patients demonstrated clonal evolution during the course of the disease. All responded initially to therapy with hydroxyurea with control of leukocytosis and reduction in splenomegaly. Three patients eventually became refractory to hydroxyurea, manifesting progressive neutrophilia without blastic transformation. Aggressive chemotherapy to control progressive leukocytosis resulted in death due to cytopenias in two of these patients. The third patient received less intensive chemotherapy and died of progressive disease. One patient died after transformation of the disease into undifferentiated acute myeloid leukemia. Two patients remain alive with stable disease on hydroxyurea therapy, 12 and 54 months after initial diagnosis. Chronic neutrophilic leukemia is a rare clinicopathologic entity that can be distinguished from chronic myelogenous leukemia, the recently described neutrophilic-chronic myelogenous leukemia, and myelodysplastic syndrome. The clinical course is heterogeneous, with a definite risk of death from either blastic transformation or progressive neutrophilic leukocytosis. Continued study and reporting of these cases must be encouraged. [ABSTRACT FROM AUTHOR]
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- 2001
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11. HLA-linked complement polymorphisms (C2, BF) in psoriasis.
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Dewald, G., Lange, C., Schmeel, E., and Kreysel, H.
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Starting from the known association between psoriasis and several HLA antigens and from the fact that the HLA chromosomal region contains the structural genes for at least three complement components, the authors have looked for an association between psoriasis and allotypes of C2 and BF. C2 and BF polymorphism were examined in 230 psoriatic patients. Two rare complement genes were found to be significantly increased when compared with controls: the frequency of the C22 gene was 0.061 among patients and 0.035 among controls ( P<0.05); for BFSO7, the frequencies were 0.0304 in patients and 0.0092 in controls ( P<0.0005). The BFF gene frequency, however, was significantly decreased among patients: 0.1196 vs. 0.1743 ( P<0.01). The relative risks were 1.79 for the C22, 3.44 for the BF SO7, and 0.6 for the BFF gene product. From previous studies, it is known that these three complement alleles ( C22, BF SO7, BFF) are in linkage disequilibrium with HLA alleles that have also been found increased or decreased, respectively, in psoriasis. [ABSTRACT FROM AUTHOR]
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- 1983
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12. C6-Polymorphismus der sechsten Komplementkomponente.
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Rittner, Ch., Dewald, G., Berghoff, E., and Mollenhauer, E.
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Copyright of Zeitschrift für Rechtsmedizin is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 1979
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13. A retrospective study of 69 patients with t(6;9)(p23;q34) AML emphasizes the need for a prospective, multicenter initiative for rare ‘poor prognosis’ myeloid malignancies.
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Slovak, M L, Gundacker, H, Bloomfield, C D, Dewald, G, Appelbaum, F R, Larson, R A, Tallman, M S, Bennett, J M, Stirewalt, D L, Meshinchi, S, Willman, C L, Ravindranath, Y, Alonzo, T A, Carroll, A J, Raimondi, S C, and Heerema, N A
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LETTERS to the editor ,LEUKEMIA - Abstract
A letter to the editor is presented in response to the article "A retrospective study of 69 patients with t(6;9)(p23;q34) AML emphasizes the need for a prospective, multicenter initiative for rare ‘poor prognosis’ myeloid malignancies" that appeared online in the April 20, 2006 issue of "Leukemia."
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- 2006
- Full Text
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