K Miyazawa

Tokyo Medical University, Tokyo, Tokyo-to, Japan

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Publications (59)220.3 Total impact

  • Article: Uncontrolled thrombocytosis in polycythemia vera is a risk for thrombosis, regardless of JAK2(V617F) mutational status.
    Leukemia: official journal of the Leukemia Society of America, Leukemia Research Fund, U.K 01/2008; 21(12):2544-5. · 8.30 Impact Factor
  • Article: Uncontrolled thrombocytosis in polycythemia vera is a risk for thrombosis, regardless of JAK2V617F mutational status
    Leukemia 07/2007; 21(12):2544-2545. · 9.56 Impact Factor
  • Article: Clinical usefulness of transcription-mediated amplification and hybridization protection assay in imatinib-treated chronic myelogenous leukemia patients.
    Clinical & Laboratory Haematology 01/2006; 27(6):416-7. · 1.11 Impact Factor
  • Article: The JAK2 V617F tyrosine kinase mutation in myelodysplastic syndromes (MDS) developing myelofibrosis indicates the myeloproliferative nature in a subset of MDS patients.
    Leukemia 01/2006; 19(12):2359-60. · 9.56 Impact Factor
  • Article: Combination of 22-oxa-1,25-dihydroxyvitamin D(3), a vitamin D(3) derivative, with vitamin K(2) (VK2) synergistically enhances cell differentiation but suppresses VK2-inducing apoptosis in HL-60 cells.
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    ABSTRACT: We originally reported that vitamin K(2) (VK2) effectively induces apoptosis in various types of primary cultured leukemia cells and leukemia cell lines in vitro. In addition, VK2 was shown to induce differentiation of leukemia cells when the cells were resistant against VK2-inducing apoptosis. A novel synthetic vitamin D(3)derivative, 22-oxa-1,25-dihydroxyvitamin D(3) (OCT: oxacarcitriol) shows a more potent differentiation-inducing ability among myeloid leukemia cells in vitro with much lesser extent of the induction of hypercalcemia in vivo as compared to the effects of 1alpha,25(OH)(2)D(3). In the present study, we focused on the effects of a combination of OCT plus VK2 on leukemia cells. Treatment of HL-60 cells with OCT for 72 h induces monocytic differentiation. A combination of OCT plus VK2 dramatically enhances monocytic differentiation as assessed by morphologic features, positivity for non-specific esterase staining, and cell surface antigen expressions. This combined effect far exceeds the maximum differentiation induction ability at the optimal concentrations of either OCT or VK2 alone. In addition, pronounced accumulation of the cells in the G0/G1 phase is observed by combined treatment with OCT plus VK2 as compared with each vitamin alone. In contrast to cell differentiation, caspase-3 activation and apoptosis induction in response to VK2 are significantly suppressed in the presence of OCT in HL-60 cells. These data suggest that monocytic differentiation and apoptosis induction of HL-60 cells are inversely regulated. Furthermore, pronounced induction of differentiation by combined treatment with VK2 plus OCT was also observed in four out of six cases of primary cultured acute myeloid leukemia cells in vitro, suggesting that VK2 plus OCT might be a potent combination for the differentiation-based therapy for acute myeloid leukemias.
    Leukemia 09/2002; 16(8):1519-27. · 9.56 Impact Factor
  • Article: Myelodysplastic syndrome accompanied by Addison's disease and multiple autoimmune phenomena: steroid therapy resolved cytopenias and all immune disorders.
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    ABSTRACT: We report here a patient with myelodysplastic syndromes (MDS), which was complicated with several autoimmune disorders and asymptomatic immunologic abnormalities. An 82-year-old woman with refractory anemia (RA) rapidly developed thrombocytopenia with the appearance of symptoms such as purpura, fatigue, anorexia, and weight loss. Furthermore, clinical examinations revealed that she also had Addison's disease, rheumatoid arthritis, and autoimmune hematological diseases such as thrombocytopenia and hemolytic anemia. However, the cytopenia and all autoimmune disorders were remarkably improved after she received steroid therapy.
    Internal Medicine 11/2001; 40(10):1041-4. · 0.94 Impact Factor
  • Article: Re-evaluation of refractory anemia with excess blasts in transformation.
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    ABSTRACT: The category 'refractory anemia with excess blasts in transformation (RAEBt)' consists of two sub-sets; one group is categorized based on the percentage of blasts in the marrow (> or =20%) and other is based on the percentage of blasts in the peripheral blood (> or =5%). We separated RAEBt patients based on these two criteria and compared hematologic and clinical relevance to assess the reasonable basis for the new classification. All RAEBt patients showing peripheral blood (PB) blasts of > or =5% were re-classified as RAEB by the WHO classification. This subset of RAEBt patients had lower percentages of bone marrow (BM) blasts, and notably they showed frequent complex cytogenetic abnormalities, including -5/5q- and/or -7/7q-. Moreover, the RAEBt patients of this group had shorter survivals compared to RAEBt patients with BM blasts between 20 and 30%. We next assessed hematologic and clinical relevance between refractory anemia with excess blasts (RAEB) and RAEBt patients with PB blasts of > or =5%. Except for the percentage of blasts in the PB (P=0.0037) and BM (P=0.0073), there was no significant difference in hematologic or clinical features between RAEB patients with BM blasts of > or =11% and RAEBt patients with PB blasts of > or =5%. When MDS patients with PB blasts of > or =5% (RAEBt by the FAB classification) were included as RAEB-II based on the "MDS 2000 classification', there was a high frequency of patients with complex chromosome changes, involving 5q and 7q, with significant poorer outcome compared to those with RAEB-I. Although it is still controversial whether MDS patients with BM blasts 20% or more should be considered as acute leukemia, the utilization of the 'MDS 2000 classification' might be useful to designate MDS patients diagnosed based on the percentage of blasts in the peripheral blood.
    Leukemia Research 11/2001; 25(11):933-9. · 2.92 Impact Factor
  • Article: Successful treatment with cyclosporin A for myelodysplastic syndrome with erythroid hypoplasia associated with T-cell receptor gene rearrangements.
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    ABSTRACT: Myelodysplastic syndrome (MDS) with erythroid hypoplasia, a rare form of MDS, has not yet been clearly defined. We report four patients with MDS with erythroid hypoplasia who received immunosuppressive therapy. All were elderly, had severe transfusion-dependent anaemia, morphological evidence of myelodysplasia and a low percentage (3.2-13.6%) of erythroid precursors. Administration of cyclosporin A (CsA) improved their anaemia; all transfusion-dependent patients achieved transfusion-independence. An inverted CD4/8 ratio was seen in three patients who also demonstrated T-cell receptor (TCR)-beta and -gamma gene rearrangements by Southern blotting and clonality by polymerase chain reaction. Treatment with CsA can be an attractive alternative treatment for patients with MDS with erythroid hypoplasia, which may be associated with a clonal abnormality in T cells.
    British Journal of Haematology 09/2001; 114(2):358-61. · 4.94 Impact Factor
  • Article: [Pulmonary Kaposi's sarcoma successfully diagnosed by transbronchial lung biopsy].
    Nihon Naika Gakkai Zasshi 08/2001; 90(7):1345-7.
  • Article: Apoptosis/differentiation-inducing effects of vitamin K2 on HL-60 cells: dichotomous nature of vitamin K2 in leukemia cells.
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    ABSTRACT: We originally reported that vitamin K2 (VK2) analogs, including menaquinone 4 (MK4) but not vitamin K1, effectively induce apoptosis in various types of primary cultured leukemia cells and leukemia cell lines in vitro. It has also been reported by others that VK2 showed the differentiation-inducing activity in leukemia cell lines. To investigate the discrepancy between apoptosis- and differentiation-inductions of leukemia cells by VK2 treatment, we used bcl-2 gene transfected HL-60 cells (HL-60-bcl-2) which resulted in five-fold over-expression of BCL-2 protein, and then compared the effects of MK4 to the control HL-60-neo cells. Seventy-two hours of exposure to various concentrations of MK4 resulted in growth inhibition of these cells in a dose-dependent manner (0.1-50 microM), however, HL-60-bcl-2 was less sensitive against MK4. MK4 potently induced apoptosis of HL-60-neo cells along with the depolarization of mitochondrial membrane potential and caspase-3 activation. Notably, HL-60-bcl-2 was almost completely resistant to apoptosis induction in response to MK4, although cell growth inhibition was still observed. In spite of the abrogation of apoptosis induction, about 90% of HL-60-bcl-2 cells were arrested in the G0/G1 phase within 48 h of exposure to 10 microM of MK4 accompanied by up-modulation of p27KIP1 expression. Concomitantly, HL-60-bcl-2 cells underwent monocytic differentiation. These data suggest that VK2 also shows the differentiation inducing effects on leukemia cells which are resistant against VK2-inducing apoptosis. The dichotomous nature of VK2 against leukemia cells appears to have clinical benefits for the treatment of patients with leukemias and myelodysplastic syndromes.
    Leukemia 08/2001; 15(7):1111-7. · 9.56 Impact Factor
  • Article: MALT lymphoma originating in breast and uvula.
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    ABSTRACT: A case of marginal zone B cell lymphoma of MALT type arising in the uvula and breast is reported. The patient, a 30-year-old woman who delivered a child and lactated in 1997, was suffering from Sjögren syndrome (SS). She was diagnosed with MALT lymphoma after a biopsy of the right breast and uvula. To investigate the relationship of the delivery, lactation and MALT lymphoma, we examined the immunohistochemical analysis of hormone receptors. As a result, lymphoid cells of the breast were stained with anti-progesterone receptor antibodies in the cytoplasm. Consequently, the MALT lymphoma of the uvula appeared to be associated with SS. Moreover, hormones such as progesterone may have influenced the breast involvement of MALT lymphoma in our case.
    Leukemia and Lymphoma 05/2001; 41(3-4):461-3. · 2.58 Impact Factor
  • Article: Anaplastic large-cell lymphoma which showed severe inflammatory status and myelodysplasia with increased VEGF and IL-6 serum levels after long-term immunosuppressive therapy.
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    ABSTRACT: We report a patient with anaplastic large-cell lymphoma (ALCL) who has been given immunosuppressive therapy for Evans syndrome for 10 years. He was admitted with spike fever, intra-abdominal lymphadenopathy, and multiple liver masses. Examination of biopsy specimens obtained by para-aortic lymph nodes and liver masses resulted in a diagnosis of ALCL. Immunohistochemically, these cells were reactive to anti-CD30 antibody but were not of B- or T-lineage. Bone marrow aspiration demonstrated the invasion of giant neoplastic cells and trilineage myelodysplasia. Because the patient showed severe inflammatory symptoms, we examined serum levels of various cytokines. Pretreatment levels of IL-6 and VEGF in this patient were significantly elevated compared to those of normal controls. He was treated with combination chemotherapy (ABVD regimen), achieving complete remission. Myelodysplasia and serum IL-6 and VEGF also normalized after treatment. We assumed that ALCL resulted from long-term immunosuppressive therapy and that the up-regulation of IL-6 and VEGF played a role in pathogenesis of this type of lymphoma.
    American Journal of Hematology 02/2001; 66(1):49-52. · 4.67 Impact Factor
  • Article: [Rapidly progressive fibrosis and increased CD68-positive cells in the bone marrow at the terminal stage of adult T-cell leukemia accompanied by polycythemia vera].
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    ABSTRACT: We report a case of adult T-cell leukemia (ATL) accompanied by polycythemia vera (PV) in which rapid development of myelofibrosis and clinical features of hemophagocytic syndrome (HPS) were observed at the terminal stage. The patient, a 53-year-old man who was born in Oita Prefecture, Japan, was diagnosed as having PV in 1996. He had undergone venesection but had not received any chemotherapy. In June 1997, he showed systemic lymphadenopathy with positivity for serum HTLV-1 antibody (x 10,240). Pathological findings and Southern blotting analysis for detection of monoclonal integration of HTLV-1 provirus DNA in a lymph node biopsy sample revealed that he also had acute-type ATL. Although several courses of chemotherapy were transiently effective, high fever, pancytopenia, increased serum LDH, hypoproteinemia and hyperferritinemia appeared, all of which were compatible with the clinical features of HPS. In addition, cytomegalovirus infection became evident. He died of multiple organ failure with rapid progression of myelofibrosis in May 1998. Detection of both increased CD68-positive histiocytes by immunohistochemistry and iron-stained phagocytic cells in marrow biopsy specimens appeared to be helpful for diagnosis of HPS in this patient, whose marrow showed myelofibrosis with hypocellularity.
    [Rinshō ketsueki] The Japanese journal of clinical hematology 01/2001; 41(12):1254-9.
  • Article: Nuclear accumulation of beta-catenin in intestinal-type gastric carcinoma: correlation with early tumor invasion.
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    ABSTRACT: Mutation of the adenomatous polyposis coli gene, which is known to be an early event in the carcinogenesis of intestinal-type gastric carcinoma, leads to accumulation of beta-catenin. In addition, beta-catenin has been found to activate down stream signaling molecules in the wingless/Wnt pathway. In this study, the clinical significance of nuclear accumulation of beta-catenin was evaluated in gastric carcinoma. Immunohistochemical staining showed nuclear localization in 16 (12%) of 139 (94 intestinal-type and 45 diffuse-type) gastric carcinomas, and all 16 lesions with nuclear staining were intestinal-type adenocarcinomas. Of the 16 cases, 15 were in the early clinical stage. In the remaining case, the lesion had invaded the subserosal layer and showed strong nuclear staining at the invasive front. In 14 of the 16 cases with nuclear localization, there were no abnormal mobility shifts detected using polymerase chain reaction-single strand conformational polymorphism analysis. This was confirmed using direct sequencing analysis, which revealed the wild-type sequence in the 12 cases tested. Nuclear accumulation of beta-catenin did not correlate with lymph node metastasis or 5-year survival. These findings suggest that high intranuclear levels of beta-catenin protein play an important role in early tumor growth and may function in initiation of invasive processes in intestinal-type gastric carcinoma.
    Archiv für Pathologische Anatomie und Physiologie und für Klinische Medicin 12/2000; 437(5):508-13. · 2.49 Impact Factor
  • Article: Combination of granulocyte colony-stimulating factor and low-dose cytosine arabinoside further enhances myeloid differentiation in leukemia cells in vitro.
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    ABSTRACT: We examined the differentiation-inducing effect on freshly isolated myeloid leukemia cells in liquid suspension culture by combined treatment with granulocyte colony-stimulating factor (G-CSF) plus low-dose cytosine arabinoside (Ara-C; 5-10 ng/ml) in 25 patients with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) in leukemic transformation. Culture with G-CSF alone showed leukemic cell growth stimulation in 15 out of the 25 cases (60%) and induction of cell differentiation in 19 out of the 25 cases (76%), respectively. In 23 cases (92%), either growth stimulation and/or differentiation induction of leukemia cells was observed in response to G-CSF. This suggests that most myeloid leukemia cells are able to respond to G-CSF stimulation. In addition, treatment of cells with low-dose Ara-C alone resulted in the enhancement of myeloid specific antigens expression in 16 cases (64%). Treatment of leukemia cells with higher concentrations of Ara-C (over 50 ng/ml) alone resulted in cytocidal effects but not in the induction of differentiation. Furthermore, 15 cases (60%) showed pronounced myeloid differentiation of leukemia cells after combined exposure to G-CSF plus low-dose Ara-C as compared with cells treated with either G-CSF or Ara-C alone. The enhanced effect of differentiation induction by combining G-CSF plus low-dose Ara-C was also observed in a murine myeloid leukemia cell line WEHI-3B in vitro. These data suggest that treatment with G-CSF plus low-dose Ara-C is capable of inducing differentiation of leukemic cells in vitro, and also appears to be useful for the differentiation-based therapy of patients with AML and MDS.
    Leukemia and Lymphoma 10/2000; 39(1-2):173-84. · 2.58 Impact Factor
  • Article: [Intrafamilial epidemic of meningococcal meningitis].
    Nihon Naika Gakkai Zasshi 09/2000; 89(8):1642-4.
  • Article: Refractory anemia with ringed sideroblasts with a low IPSS score progressed rapidly with de novo appearance of multiple karyotypic abnormalities and into acute erythroleukemia (AML-M6A).
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    ABSTRACT: We report here a case of refractory anemia with ringed sideroblasts (RARS) with a low risk group by the International Prognostic Scoring System (IPSS) at the time of diagnosis but had a rapid disease progression. Although the patient showed a normal male karyotype at the time of RARS diagnosis, his marrow cells had del(5)(q14) and add(17)(p12) abnormalities 2 months after the diagnosis, and later the marrow cells had multiple abnormalities and the patient expired 6 months after the initial diagnosis of RARS. The patient was diagnosed as having RARS with a low risk group by the IPSS classification, however, one should keep in mind that some patients with myelodysplastic syndromes with low risks by either the French-American-British (FAB) classification or the IPSS classification may have progressive disease and subsequential cytogenetic analysis could predict the disease progression.
    Leukemia Research 08/2000; 24(7):597-600. · 2.92 Impact Factor
  • Article: [Diffuse large B-cell lymphoma showing CNS invasion by CD30-positive multinuclear giant cells mimicking the clinical features of progressive multifocal leukoencephalopathy].
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    ABSTRACT: We report a 55-year-old woman with diffuse large B-cell lymphoma showing central nervous system (CNS) infiltration by CD30-positive lymphoma cells. The patient was admitted with pleural effusion, ascites and a large mass in the abdominal cavity. Southern blot analysis of DNA extracted from the ascites revealed IgJH rearrangement, and therefore she was initially diagnosed as B-cell neoplasia. She received combined chemotherapy (DICE and CHOP regimens), and achieved a transient clinical response. Three months later, she developed various neurological abnormalities, and brain magnetic resonance imaging revealed diffuse infiltration of the cerebral white matter. We considered the possibility of CNS involvement by the lymphoma or progressive multifocal leukoencephalopathy (PML), and began a course of anti-virus therapy and radiation therapy. Because multiple lumbar punctures demonstrated large multinuclear lymphoma cells in the cerebrospinal fluid, a diagnosis of metastatic CNS lymphoma was made. Immunohistochemistry revealed that these lymphoma cells were reactive with anti-CD30 antibody. Although the radiation therapy was temporarily effective against the CNS involvement, the patient died of systemic invasion of the lymphoma cells. The final diagnosis was diffuse large B-cell lymphoma on the basis of pathologic findings, immunohistochemistry, and Southern blot analysis using a mesenteric lymph node obtained at autopsy. Cytospin preparations and immunohistochemistry of specimens obtained from frequent lumbar punctures were useful for differentiating CNS lymphoma from PML.
    [Rinshō ketsueki] The Japanese journal of clinical hematology 07/2000; 41(6):507-12.
  • Article: Comparative multi-color flow cytometric analysis of cell surface antigens in bone marrow hematopoietic progenitors between refractory anemia and aplastic anemia.
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    ABSTRACT: Refractory anemia (RA) in myelodysplastic syndrome (MDS) without prominent dysplasia closely resemble the mild type of aplastic anemia (AA) in their hematological features. This sometimes makes it difficult to distinguish clearly between the two diseases. Using the multi-color flow cytometric technique, we compared cell surface antigen expression patterns on bone marrow hematopoietic progenitor cells which were isolated as a CD34 positive- CD45 dull positive with low side scatter intensity (CD34(+)CD45(dull+)SSC(low)) population in flow cytogram between RA (n=12) and AA (n=11). The antigens analyzed in CD34(+)CD45(dull+)SSC(low) mononuclear cells were: CD38 and CD71 for cell growth-related antigens, CD 33 and CD13 for myeloid and monocytoid lineage-associated antigens, CD7 and CD19 for lymphoid lineage, and CD14 for a monocytic lineage specific antigen. The percentages of CD34(+)CD45(dull+)SSC(low) cells in bone marrow non-erythroid mononuclear cells, and the expression frequencies of CD38, CD71, CD33 and CD13 antigens in CD34(+)CD45(dull+)SSC(low) progenitors were all significantly decreased in AA compared to normal bone marrows (n=7) (P<0.005). In contrast, in RA bone marrows the percentages of CD34(+)CD45(dull+)SSC(low) cells showed wide distribution and the cell surface antigen expression patterns varied among each case: some cases showed low frequencies of CD38 and CD71 expression as well as AA, whereas the others showed high expression frequency of specific antigen(s) which may reflect the clonal expansion of an abnormal clone in bone marrow. An MDS patient who had progressed from RA to RAEB showed further projecting pattern of expression of CD38 and CD33 in CD34(+)CD45(dull+)SSC(low) population in accordance with the disease progression. These data suggest that analysis of cell surface antigen expression patterns of CD34(+)CD45(dull+)SSC(low) progenitor cells by multi-color flow cytometry appears to be a useful method for qualitative and quantitative assessment of marrow progenitor states in AA and RA, therefore this method could be helpful for early detection of clonal evolution in MDS.
    Leukemia Research 04/2000; 24(4):359-66. · 2.92 Impact Factor
  • Article: Spontaneous reduction of leukemic lymphoma cells possibly by anti-tumor antibody-mediated phagocytosis; a kappa lambda-dual-positive B cell lymphoma.
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    ABSTRACT: We have investigated the possible role of anti-tumor antibody detected in a case of follicular lymphoma which demonstrated the spontaneous reduction of leukemic tumor cells. The tumor cells genotypically had monoclonal rearrangements of the immunoglobulin J H and C kappa genes, but phenotypically exhibited surface IgG, A, kappa and lambda (kappa lambda dual positivity). The culture study revealed that IgGlambda, at least, was derived from the serum, and IgAkappa was expressed intrinsically. Furthermore, the positive correlation between the densities of both surface light chains on two-color flow cytometry, the rosette formation study and its inhibition test by the Fcgamma fragment suggested that the serum IgGlambda combined with some antigens on the tumor-cell surface via its Fab portion and with the Fcgamma receptor of macrophages via its Fc portion. From these findings, we regarded the present case as an anti-tumor antibody-coated lymphoma. In addition, the phagocytic study disclosed that the serum-derived IgGlambda, at least, might have induced the phagocytosis of circulating lymphoma cells by macrophages. In conclusion, the existence of the anti-tumor antibody-coated lymphoma may be helpful in clarifying the immunological mechanism of the spontaneous regression occasionally seen in lymphomas.
    Leukemia 03/2000; 14(2):278-84. · 9.56 Impact Factor