Junichi Tsukada

Kitakyushu University, Kitakyūshū, Fukuoka, Japan

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Publications (102)242.04 Total impact

  • [Show abstract] [Hide abstract] ABSTRACT: We previously reported that the inflammasome inhibitor cucurbitacin D (CuD) induces apoptosis in human leukemia cell lines. In the present study, we investigated the effects of co-treatment with an additional Bcl-xL inhibitor, Z36. Treatment with Z36 induced cell death in leukemia cell lines, with MT-4 cells exhibiting the lowest sensitivity to Z36. Co-treatment of cells with Z36 and CuD resulted in a greater degree of cell death for Hut78 and Jurkat cells than treatment with CuD alone. In contrast, co-treatment of MT-4 cells with Z36 and CuD had a suppressive effect on cell death. The autophagy inhibitor 3-methyladenine (3-MA) suppressed the growth of leukemia cell lines HuT78, Jurkat, MT-1, and MT-4. CuD-induced cell death was enhanced by 3-MA in Jurkat cells, but inhibited in MT-4 cells. Western blotting results revealed cleavage of poly(ADP ribose) polymerase (PARP), supporting CuD-induced cell death; 3-MA enhanced CuD-Z36-induced PARP cleavage. Taken together, our results indicate that autophagy negatively regulates chemical-induced cell death of leukemia cells, and that controlling autophagy could be beneficial in the development of more effective chemotherapies against leukemia.
    No preview · Article · Feb 2016 · Medical Oncology
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    [Show abstract] [Hide abstract] ABSTRACT: Background Plasmablastic lymphoma (PBL) is a rare and aggressive subtype of non-Hodgkin diffuse large B-cell lymphoma originally with a predilection to the oral cavity of patients infected with HIV. However, PBL of extraoral sites possesses clinicopathological characteristics distinct from oral PBL. Recently, therapeutic approaches using a proteasome inhibitor bortezomib to PBL of extraoral sites have been reported. We present a PBL patient with a bulky tumor of the oral cavity, who dramatically responded to bortezomib. Case Presentation The patient was a 58 year-old Japanese male, who presented with a rapidly progressive history of a swelling on his left cheek and restricted mouth opening. He did not have a history or evidence of immunosuppression including HIV infection. A computed tomography demonstrated a bulky tumor in the oral cavity without enlarged lymph nodes. The tumor showed the proliferation of large lymphoid cells with centroblastic morphology, which were positive for CD138, CD38, CD56 and MUM-1, and negative for CD20, CD79a, BCL-6 and HHV8. The Ki-67 proliferation index was almost 100 %. Neither osteolytic lesions nor M-protein was observed. One week after the initiation of bortezomib, a marked regression of the oral tumor was obtained. Conclusions Thus, our case demonstrated the effectiveness of bortezomib on PBL of the oral cavity as well as the extraoral sites.
    Preview · Article · Nov 2015
  • No preview · Article · Nov 2015 · Annals of Oncology
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    [Show abstract] [Hide abstract] ABSTRACT: Primary hepatic lymphoma (PHL) is an extremely rare disease, frequently associated with viruses such as hepatitis B virus (HBV), hepatitis C virus (HCV), and human immune deficiency virus (HIV). On the other hand, an increased risk of lymphoproliferative disorders (LPD) has been demonstrated in patients treated with immunosuppressive drugs such as methotrexate (MTX) for rheumatoid arthritis (RA). The role of Epstein-Barr virus (EBV) has been discussed in the pathogenesis of the immunodeficiency-associated LPDs. We here describe a RA patient, who developed PHL during RA treatment. The patient was a 64 year-old Japanese male with a 2-year history of RA, who had been treated with MTX at weekly dose of 8-14 mg for 2 years and infliximab (IFX) for 7 months. He presented with a 2 month history of generalized malaise, right hypochondrium pain and fever. Contrast-enhanced computed tomography (CECT) of the abdomen showed multiple irregular and nodular liver masses with a maximum of 13 cm in diameter on the right liver. Biopsy specimens demonstrated CD20-positve diffuse large B-cell lymphoma (DLBCL), but EBV was not identified by EBV-encoded RNA in situ hybridization. Serology for HBV, HCV, human T-cell leukemia virus I (HTLV-I), and HIV was negative. His symptoms disappeared following discontinuation of RA treatment including MTX. A drastic regression of the tumor masses was further obtained without cytotoxic chemotherapy. In addition, although the patient had no past history of liver dysfunction before MTX therapy, persistent elevation of liver enzymes has been observed during MTX treatment. These findings show a causative role of MTX in the development of reversible PHL in the patient.
    Preview · Article · May 2015
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    Preview · Dataset · Feb 2015
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    Preview · Dataset · Feb 2015
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    Preview · Dataset · Feb 2015
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    [Show abstract] [Hide abstract] ABSTRACT: SMARCE1 gene is a SWI/SNF-related, matrix-associated and actin-dependent regulator of chromatin, subfamily e, member 1, which encodes BAF57 protein. Previously, we reported that BAF57 is a predictive marker of endometrial carcinoma. In this study, we investigated BAF57 expression in ovarian cancer cell lines and their sensitivities to cisplatin, doxorubicin, paclitaxel, and 5-fluorouracil (5-FU). BAF57 expression was strongly correlated with sensitivities to cisplatin, doxorubicin, and 5-FU in 10 ovarian cancer cell lines. Paclitaxel sensitivity was also correlated with BAF57 expression, but without significance. In A2780 ovarian cancer cells, knockdown of BAF57 using specific siRNA increased cell cycle arrest at G1 phase and the sensitivities to these anti-cancer agents. cDNA microarray analysis of A2780 cells transfected with BAF57 siRNA showed that 134 genes were positively regulated by BAF57, including ATP-binding cassette, sub-family G (WHITE), member 2 (ABCG2) encoding breast cancer resistance protein (BCRP). We confirmed that knockdown of BAF57 decreased BCRP expression in ovarian cancer cells by western blot analysis, and that ABCG2 gene expression might be regulated transcriptionally. These results suggested that BAF57 is involved in ovarian cancer cell growth and sensitivity to anti-cancer agents, and that BAF57 may be a target for ovarian cancer therapy.This article is protected by copyright. All rights reserved.
    Preview · Article · Jan 2015 · Cancer Science
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    [Show abstract] [Hide abstract] ABSTRACT: Background and Objectives Previously, a weak phenotype Am or Bm was assumed to be caused by a reduction of A or B gene expression in bone marrow cells, but not in mucus-secreting cells. However, ABO expression has not been examined in erythroid progenitor cells of Am or Bm individuals.Materials and Methods We carried out in vitro erythroid differentiation of CD34+ cells from peripheral blood of a Bm individual harbouring a 3·0-kb deletion including an erythroid cell-specific regulatory element, named the +5·8-kb site, in intron 1 of the human ABO blood group gene.ResultsDuring the in vitro differentiation of CD34+ cells from this Bm individual into erythroid cells, B-antigens were not detectable on the cultured cells by flow cytometric analysis, and allele-specific RT-PCR consistently detected the transcripts from the O allele, but not from the B allele. Moreover, chromatin immunoprecipitation assay demonstrated that both RUNX1 and GATA-2 or GATA-1 were bound to the +5·8-kb site in cultured erythroid cells expressing ABO.Conclusion It is likely that the +5·8-kb site enhances transcription from the ABO promoter in erythroid cells through binding of RUNX1 and GATA-2 or GATA-1.
    Full-text · Article · Nov 2014 · Vox Sanguinis
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    [Show abstract] [Hide abstract] ABSTRACT: Background The ABO blood group is important in blood transfusion. Recently, an erythroid cell-specific regulatory element has been identified in the first intron of ABO using luciferase reporter assays with K562 cells. The erythroid cell-specific regulatory activity of the element was dependent upon GATA-1 binding. In addition, partial deletion of Intron 1 including the element was observed in genomic DNAs obtained from 111 B-m and AB(m) individuals, except for one, whereas the deletion was never found among 1005 individuals with the common phenotypes. Study Design and Methods In this study, further investigation was performed to reveal the underlying mechanism responsible for reduction of B antigen expression in the exceptional B-m individual. Peptide nucleic acid-clamping polymerase chain reaction was carried out to amplify the B-related allele, followed by sequence determination. Electrophoretic mobility assays and promoter assays were performed to examine whether a nucleotide substitution reduced the binding of a transcription factor and induced loss of function of the element. ResultsSequence determination revealed one point mutation of the GATA motif in the element. The electrophoretic mobility shift assays showed that the mutation abolished the binding of GATA transcription factors, and the promoter assays demonstrated complete loss of enhancer activity of the element. Conclusion These observations suggest that the mutation in the GATA motif of the erythroid-specific regulatory element may diminish the binding of GATA transcription factors and down regulate transcriptional activity of the element on the B allele, leading to reduction of B antigen expression in erythroid lineage cells of the B-m individual.
    Full-text · Article · Apr 2013 · Transfusion
  • [Show abstract] [Hide abstract] ABSTRACT: We report a case of adult T-cell leukemia/lymphoma (ATL) with rapidly progressive pulmonary areas of ground-glass attenuation (GGA) and nodules resulting from acute transformation of chronic ATL. A 48-year-old Japanese man was admitted for progressive dyspnea. Chest computed tomography showed rapidly progressive bilateral pulmonary areas of GGA and nodules. Flow cytometry of bronchoalveolar lavage fluid and immunohistochemical examination of lung biopsy specimens revealed invasion of ATL cells. Systemic chemotherapy improved the pulmonary findings. Rapidly expanding areas of GGA and nodules are a rare manifestation of pulmonary invasion of ATL that clinicians should nevertheless keep in mind.
    No preview · Article · Mar 2013
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    [Show abstract] [Hide abstract] ABSTRACT: The ABO blood group is of great importance in blood transfusion and organ transplantation. However, the mechanisms regulating human ABO gene expression remain obscure. On the basis of DNase I-hypersensitive sites in and upstream of ABO in K562 cells, in the present study, we prepared reporter plasmid constructs including these sites. Subsequent luciferase assays indicated a novel positive regulatory element in intron 1. This element was shown to enhance ABO promoter activity in an erythroid cell-specific manner. Electrophoretic mobility-shift assays demonstrated that it bound to the tissue-restricted transcription factor GATA-1. Mutation of the GATA motifs to abrogate binding of this factor reduced the regulatory activity of the element. Therefore, GATA-1 appears to be involved in the cell-specific activity of the element. Furthermore, we found that a partial deletion in intron 1 involving the element was associated with B(m) phenotypes. Therefore, it is plausible that deletion of the erythroid cell-specific regulatory element could down-regulate transcription in the B(m) allele, leading to reduction of B-antigen expression in cells of erythroid lineage, but not in mucus-secreting cells. These results support the contention that the enhancer-like element in intron 1 of ABO has a significant function in erythroid cells.
    Full-text · Article · Mar 2012 · Blood
  • [Show abstract] [Hide abstract] ABSTRACT: We report a 73-year-old Japanese man with early onset pure red cell aplasia (PRCA) caused by subcutaneous administration of recombinant epoetin-β. Two months after the start of epoetin therapy, he developed PRCA. Anti-erythropoietin (EPO) antibody, detected in the patient's serum by enzyme immunoassay and radioimmunoprecipitation method, inhibited EPO-dependent growth of AS-E2 cells in vitro. Treatment with prednisone (1 mg/kg) significantly reduced antibody levels 3 months later. It is important to have an awareness of antibody-mediated PRCA. Our case shows that subcutaneous epoetin administration produces this complication in the early period of therapy.
    No preview · Article · Jan 2012 · [Rinshō ketsueki] The Japanese journal of clinical hematology
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    Preview · Chapter · Oct 2011
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    [Show abstract] [Hide abstract] ABSTRACT: Human T-cell leukemia is an aggressive malignancy of T lymphocytes. T-cell leukemia has a very poor prognosis, even with intensive chemotherapy, indicating the need for development of new drugs to treat the disease. Triterpenoid cucurbitacins have been shown to have antitumor activity, but the mechanism of this activity is not fully understood. The effects of cucurbitacin D on the proliferation and apoptotic induction of T-cell leukemia cells using the Cell viability assay and Annexin V staining were evaluated. To investigate the mechanisms of apoptosis, antiapoptotic protein, NF-κB, and the proteasome activity of leukemia cells treated with cucurbitacin D were evaluated by Western blotting both in vitro and in vivo. In this study, cucurbitacin D was found to inhibit proliferation and to induce apoptosis of T-cell leukemia cells. Constitutively activated NF-κB was inhibited by cucurbitacin D in the nucleus, which resulted in accumulation of NF-κB in the cytoplasm, leading to down-regulation of the expression of antiapoptotic proteins Bcl-xL and Bcl-2. Furthermore, cucurbitacin D induced the accumulation of inhibitor of NF-κB (IκB)α by inhibition of proteasome activity. Low doses of cucurbitacin D synergistically potentiated the antiproliferative effects of the histone deacetylase inhibitor VPA. Finally, the proapoptotic and proteasome inhibitory activities of cucurbitacin D also were demonstrated using SCID mice in an in vivo study. Cucurbitacin D induced apoptosis through suppression of proteasome activity both in vitro and in vivo, making cucurbitacin D a promising candidate for clinical applications in the treatment of T-cell leukemia.
    Full-text · Article · Jun 2011 · Cancer
  • [Show abstract] [Hide abstract] ABSTRACT: The C/EBP family of proteins represents an important group of bZIP transcription factors that are key to the regulation of essential functions such as cell cycle, hematopoiesis, skeletal development, and host immune responses. They are also intimately associated with tumorigenesis and viral disease. These proteins are regulated at multiple levels, including gene induction, alternative translational initiation, post-translational modification, and protein-protein interaction. This review attempts to integrate recent reports with more than 20 years of previous effort focused on this fascinating collection of regulators.
    No preview · Article · Apr 2011 · Cytokine
  • [Show abstract] [Hide abstract] ABSTRACT: The efficacy of pirarubicin (THP)-COP was previously compared with cyclophophamide + doxorubicin + vincristine + prednisolone (CHOP) in elderly patients with lymphoma. The subset analysis showed that T-cell lymphoma had a significantly better response with THP-COP, whereas no such difference was observed in B-cell lymphoma. The aim of this study is to confirm the efficacy of THP-COP in the treatment of T-cell lymphoma. We underwent a multicenter phase II study of THP-COP as a first-line treatment for T-cell lymphoma. The overall response rate, survival period, and toxicity were analyzed. Fifty-three patients were enrolled in this study. Seventeen patients had peripheral T-cell lymphoma (PTCL), including nine of PTCL not otherwise specified (PTCL-NOS) and eight of angioimmunoblastic T-cell lymphoma (AITL). Thirty-six patients had adult T-cell leukemia/lymphoma (ATLL), including 20 of acute type and 16 of lymphoma type. A treatment response was obtained in 35 (66%) patients, including 17 (32%) complete responses. Median overall survival (OS) and progression-free survival (PFS) times were 14.3 months and 5.2 months, respectively. Patients with ATLL showed a tendency to obtain low response rate (61% vs. 77%, P = 0.27) and had a significantly inferior OS (13.3 vs. 28.6 months, P = 0.04) and PFS (4.6 vs. 8.1 months, P = 0.01) in comparison with PTCL. Grade 3 to 4 neutropenia, anemia, and thrombocytopenia occurred in 72%, 34%, and 58% of the patients, respectively. Febrile neutropenia was observed in 51% and grade 3 non-hematological toxicities in 2-9% of the patients. The efficacy of THP-COP is equivalent to that of CHOP for the first-line therapy in T-cell lymphoma.
    No preview · Article · May 2010 · European Journal Of Haematology
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    [Show abstract] [Hide abstract] ABSTRACT: The diagnosis of myelodysplastic syndromes is not always straightforward when patients lack specific diagnostic markers, such as blast excess, karyotype abnormality, and ringed sideroblasts. We designed a flow cytometry protocol applicable in many laboratories and verified its diagnostic utility in patients without those diagnostic markers. The cardinal parameters, analyzable from one cell aliquot, were myeloblasts (%), B-cell progenitors (%), myeloblast CD45 expression, and channel number of side scatter where the maximum number of granulocytes occurs. The adjunctive parameters were CD11b, CD15, and CD56 expression (%) on myeloblasts. Marrow samples from 106 control patients with cytopenia and 134 low-grade myelodysplastic syndromes patients, including 81 lacking both ringed sideroblasts and cytogenetic aberrations, were prospectively analyzed in Japan and Italy. Data outside the predetermined reference range in 2 or more parameters (multiple abnormalities) were common in myelodysplastic syndromes patients. In those lacking ringed sideroblasts and cytogenetic aberrations, multiple abnormalities were observed in 8/26 Japanese (30.8%) and 37/55 Italians (67.3%) when the cardinal parameters alone were considered, and in 17/26 Japanese (65.4%) and 42/47 Italians (89.4%) when all parameters were taken into account. Multiple abnormalities were rare in controls. When data from all parameters were used, the diagnostic sensitivities were 65% and 89%, specificities were 98% and 90%, and likelihood ratios were 28.1 and 8.5 for the Japanese and Italian cohorts, respectively. This protocol can be used in the diagnostic work-up of low-grade myelodysplastic syndromes patients who lack specific diagnostic markers, although further improvement in diagnostic power is desirable.
    Full-text · Article · Jul 2009 · Haematologica
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    [Show abstract] [Hide abstract] ABSTRACT: Whether galectin-9 plays a role in inflammatory responses remains elusive. The present study was designed to determine the role of intracellular galectin-9 in activation of inflammatory cytokine genes in human monocytes. Galectin-9 expression vector pBKCMV3-G9 was transiently co-transfected into THP-1 monocytic cells along with luciferase reporters carrying gene promoters of IL-1alpha (IL1A), IL-1beta (IL1B) and IFNgamma. Transient transfection studies showed that galectin-9 over-expression activated all three gene promoters, suggesting that intracellular galectin-9 induces inflammatory cytokine genes in monocytes. Galectin-9 over-expression also activated NF-IL6 (C/EBP beta) and AP-1, but not NF-kappaB. In contrast, extracellular galectin-9 is not involved in regulation of inflammatory cytokines. Immunoprecipitation/Western blotting, using anti-galectin-9 Ab and anti-NF-IL6 Ab, showed physical association of intracellular galectin-9 with NF-IL6. RT-PCR confirmed that galectin-9 over-expression increased IL-1alpha and IL-1beta mRNA levels in THP-1 cells. The interaction of galectin-9 with NF-IL6 was enhanced following LPS treatment in THP-1 cells. Intracellular galectin-9 synergized with LPS to activate NF-IL6. Nuclear translocation of galectin-9 was also observed in THP-1 cells treated with LPS. Our results indicate that galectin-9 is a LPS-responsive factor, and further demonstrate that intracellular galectin-9 transactivates inflammatory cytokine genes in monocytes through direct physical interaction with NF-IL6.
    Full-text · Article · May 2009 · Genes to Cells
  • No preview · Article · May 2009 · Leukemia Research

Publication Stats

1k Citations
242.04 Total Impact Points

Institutions

  • 2014
    • Kitakyushu University
      Kitakyūshū, Fukuoka, Japan
  • 1989-2011
    • University of Occupational and Environmental Health
      • School of Medicine
      Kitakyūshū, Fukuoka, Japan
  • 1994-1998
    • Harvard Medical School
      • • Department of Pathology
      • • Department of Medicine
      Boston, Massachusetts, United States