Biomedical subjects
Publications and source records attributed to Kazuma Ohyashiki.
We report a patient with myelodysplastic syndrome (refractory anemia) showing the karyotype 46,XY,+1,der(1;10)(q10;p10), resulting in trisomy 1q and monosomy 10q abnormality. This finding suggests that either trisomy of 1q or centromeric connection between chromosomes 1 and 10, rather than the absence of 10q, might be essential toward neoplastic transformation.
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We searched for the Chlamydia psittaci DNA the touchdown enzyme time release PCR (TETR-PCR) in 23 specimens from 21 patients with ocular adnexal lymphoproliferative disorders, including 12 patients with MALT lymphoma to identify C. psittaci infection. Southern hybridization of the PCR product using the C. psittaci-specific probe failed to detect C. psittaci, although three samples appeared to be positive by ethidium bromide staining. This indicates that technical approach for detecting C. psittaci infection in ocular adnexal lymphoma might be an essential in disclosing this association.
Stromal-cell-derived factor-1alpha (SDF-1alpha/CXCL12) is a potent chemoattractant for T cells. We report that Cbl family members, Cbl and Cbl-b, are tyrosine-phosphorylated after SDF-1alpha/CXCL12 stimulation of Jurkat T cells. Enhanced phosphorylation of Cbl and Cbl-b was regulated by src family kinases, and perhaps Fyn. Activated Cbl and Cbl-b interacted with Crk-L, Zap-70, Nck, PLC-gamma and Fyb after SDF-1alpha/CXCL12 stimulation, implicating association of these proteins in SDF-1alpha/CXCL12 actions. SDF-1alpha/CXCL12 did not induce tyrosine phosphorylation of Cbl or Cbl-b in Lck-deficient T cell line J.CaM1.6 or CD45-deficient T cell line J45.01. Thus, Lck Src kinase and tyrosine phosphatase CD45 are likely involved in regulating activation of Cbl family members. A functional role for Cbl and Cbl-b in migration was demonstrated by the decrease in SDF-1/CXCL12-induced migration in a T cell line in which transfected small interfering RNA for Cbl and Cbl-b decreased expression of Cbl and Cbl-b, but not MAPK activity. SDF-1alpha/CXCL12-induced chemotaxis was greatly reduced in the CD45-deficient T cell line. Our results implicate CD45, Cbl, Cbl-b, src kinases and potentially other associated proteins as mediators of SDF-1alpha/CXCL12-induced cell migration of Jurkat T cells.
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We analyzed 23 patients with myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML) showing a der(1;7)(q10;p10) [hereafter der(1;7)] to identify the exact predictive factor of this cytogenetic change. Eight (34.8%) patients, including six with MDS and two with AML patients, had a previous history of genotoxic exposure, especially radiation and/or antimetabolites. Patients with der(1;7) consisted of three groups: one third of patients had a previous history of genotoxic agents, one third had additional cytogenetic changes at the time of MDS/AML diagnosis without previous exposure history, and the remaining one third had neither a previous exposure history nor additional cytogenetic changes. The current study demonstrated that the poor outcome of MDS/AML with der(1;7) is caused by the high frequency of associated risk factors (i.e., previous history of genotoxic exposure, the presence of additional cytogenetic changes, or both). Identification of prognostic disadvantage might be required for applying the appropriate strategy in managing MDS/AML patients with rare der(1;7) abnormality.
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Therapy-related myelodysplastic syndrome (MDS) is a major problem in long-term cancer survivors, therefore early detection and prevention of therapy-related secondary neoplasia is an important issue. We searched for therapy-related MDS and analyzed cytogenetic changes in 155 patients with multiple myeloma (MM) from a single institution. Of the total 155 MM patients with cytogenetic results, 7 patients showed de novo appearance of myeloid-related cytogenetic changes, and 5/7 had -7/7q-, including 3 with der(1;7)(q10;p10): 3 patients developed MDS (i.e. 2 patients with der(1;7)(q10;p10) and 1 with a complex abnormality including -5 and 7q-). Among five patients receiving more than 2 g of melphalan, three developed MDS, and two of them showed der(1;7)(q10;p10) before or at the time of MDS diagnosis. Although morphologic identification of MDS was difficult in some cases, we concluded that the presence of 7q-, specifically der(1;7)(q10;p10), during chemotherapy involving melphalan for MM patients might indicate hidden MDS status and appropriate therapeutic options should be considered for such patients.
The deletion of the long arm of chromosome 20, or del(20q), is a common cytogenetic abnormality in various myeloid disorders but is less commonly seen in lymphoid neoplasms. Here we report a case of Waldenström macroglobulinemia with del(20q) as the sole cytogenetic anomaly. No translocation including immunoglobulin genes was identified by spectral karyotyping (SKY) analysis. Reviewing all 11 reported cases of plasma cell dyscrasia possessing sole del(20q), including our case, none of 4 cases with del(20q) as an initial anomaly developed myelodysplastic syndrome-acute myeloid leukemia (MDS/AML), but at least 3 cases with del(20q) appearing after chemotherapy developed MDS/AML at or after the time of del(20q). We propose that the del(20q) may have different clinical significance in plasma cell dyscrasia: one is when del(20q) appears at diagnosis and may involve the initial event of oncogenesis, and the other is when del(20q) appears after treatment and is associated with therapy-related and potential MDS/AML risk.
The deletion of the long arm of chromosome 20, or del(20q), is a common cytogenetic abnormality in various myeloid disorders and is known to be a favorable prognostic factor in myelodysplastic syndromes (MDS) when it is the sole change. However, del(20q) occurs with one or more cytogenetic changes when it is associated with disease progression. Here, we analyzed 33 patients with MDS and del(20q) to ascertain the risk factors in MDS. We categorized del(20q) into two groups: one with the del(20q) clone (> or =50% marrow metaphases), corresponding to genomic integrity, and the other with a late appearance of a minor del(20q) clone (<50% metaphases) with additional cytogenetic changes, representing genomic instability. Of the MDS patients with del(20q) at initial presentation, the negative factors in predicting prognosis on survival are (i) INT-2/High risk according to the International Prognostic Scoring System, (ii) any additional cytogenetic changes, or (iii) minor del(20q) clone. The late appearance of del(20q) at any phase is linked to a significantly unfavorable prognosis, thus indicating the clinical and biological heterogeneity of del(20q) in MDS.
We report the case of a patient with hypereosinophilia and invasive thymoma harboring probable clonal proliferation of CD4+, CD8+, and CD25+ T-lymphocytes. A 64-year-old woman had eosinophilia (14.1 x 10(9)/L) and an anterior mediastinal tumor with elevated levels of serum immunoglobulin E (609.8 mg/dL) and interleukin 5 (239 pg/mL). Bone marrow aspirate showed marked infiltration by morphologically normal eosinophils with a normal karyotype but no FIP1L1-PDGFRA fusion gene. Flow cytometric analysis revealed an increasing number of CD3+/CD25+ lymphocytes in the peripheral blood, and the resected thymoma had infiltrated lymphocytes with CD4/CD8/CD25 antigens. Moreover, the thymoma had T-cell receptor rearrangements with a cytogenetically clonal nature, ie, t(2;4)(p22;q26). Although the number of patients with thymoma showing hypereosinophilia is small, this case suggests that a subset of patients with thymoma may have clonal expansion of T-lymphocytes with abnormal phenotypes that affect clinical manifestations, including hypereosinophilia.
Imatinib was developed as the first molecularly targeted therapy to specifically inhibit the BCR-ABL kinase in Philadelphia chromosome (Ph)-positive chronic myeloid leukemia (CML). Because of the excellent hematologic and cytogenetic responses, imatinib has moved toward first-line treatment for newly diagnosed CML. However, the emergence of resistance to imatinib remains a major problem in the treatment of Ph-positive leukemia. Several mechanisms of imatinib resistance have been identified, including BCR-ABL gene amplification that leads to overexpression of the BCR-ABL protein, point mutations in the BCR-ABL kinase domain that interfere with imatinib binding, and point mutations outside of the kinase domain that allosterically inhibit imatinib binding to BCR-ABL. The need for alternative or additional treatment for imatinib-resistant BCR-ABL-positive leukemia has guided the way to the design of a second generation of targeted therapies, which has resulted mainly in the development of novel small-molecule inhibitors such as AMN107, dasatinib, NS-187, and ON012380. The major goal of these efforts is to create new compounds that are more potent than imatinib and/or more effective against imatinib-resistant BCR-ABL clones. In this review, we discuss the next generation of BCR-ABL kinase inhibitors for overcoming imatinib resistance.
Bortezomib is a proteasome inhibitor that can be effective in the treatment of refractory and relapsed multiple myeloma. Recently, severe pulmonary complications associated with bortezomib therapy have been reported in Japan. Because bortezomib has not yet been approved for general use in Japan and is imported by attending physicians on the request of patients, The Japanese Society of Hematology and The Japanese Society of Clinical Hematology sent urgent questionnaires to the councilors of both societies to explore the situation and the details of pulmonary complications associated with bortezomib therapy. Clinical details were available for 46 patients who had been treated with personally imported bortezomib in Japan. Seven patients (15.2%), including 3 who died from respiratory failure, showed complications definitely or probably caused by bortezomib. Of the 7 patients, 6 had a prior history of stem cell transplantation (SCT), whereas only 14 of 39 patients without lung injury had received SCT treatment (P = .033, Fisher exact test). Multivariate analysis revealed that the concomitant use of corticosteroids might reduce the risk of lung injury (P = .024; odds ratio, 0.055) and that a previous SCT might increase the risk (P = .042; odds ratio, 13.140). We summarized these data from questionnaires for a limited Japanese cohort and therefore do not know the precise incidence of lung injury linked to fatal progression. Thus, future verification concerning this matter is warranted after the approval of bortezomib for use in Japan. Clinicians should be aware of the possibility of severe pulmonary complications associated with bortezomib therapy.
Vitamin K2 (VK2) has a growth inhibitory effect on various types of cancer cells in vitro, and its efficacy has been demonstrated in clinical applications in a number of patients with leukemia and hepatocellular carcinoma. In this study, the effect of cell growth inhibition and apoptosis induction and the concomitant use of an anticancer agent by VK2 (menaquinone: MK4), on gastric cancer cell lines were examined. When 4 kinds of gastric cancer cells (KATO III, MKN7, MKN74 and FU97) were exposed to MK4, the cell growth was inhibited in an MK4 dose-dependent manner. Morphologically, apoptosis induced by MK4 was recognized in FU97, but only a slight number of apoptotic images was recognized in other cell lines. On the contrary, in all the cell lines, the percentage of APO2.7 positive cells increased significantly in the MK4-treated group as compared to the controls. Caspase-3 activity increased significantly in KATO III and FU97 as compared to the controls, while no significant differences were noted in MKN7 or MKN74. Moreover, in all the cell lines, the percentage of G0/G1-phase cells ( approximately 70% in KATO III and FU97, and > or =80% in MKN7 and MKN74) increased in comparison to the controls, suggesting that cell-cycle arrest had occurred. All of the gastric cancer cell lines were given MK4 in different concentrations and two kinds of anticancer agent, with the result that cell growth was inhibited by the anticancer agent in a dose-dependent manner when it was given with MK4 in concentrations of up to 10 microM. In conclusion, our results demonstrate that the effect of MK4 on apoptosis and cell-cycle arrest differs in differentiated (MKN7, MKN74) and undifferentiated (KATO III, FU97) gastric cancer cell lines, and that MK4 alone or with anticancer agents has an antitumor effect on gastric cancer cell lines.
A 24-year-old woman was referred to our hospital with fever and cervical lymphadenopathy. On admission, her serum concentration of soluble IL-2 receptor had increased to 1,740 IU/ml, LDH was 2,889 IU/l, and ferritin was 2,389 ng/ml. Dyspnea became evident (PaO2 60 Torr) with a further increase of serum ferritin to 96,552 mg/ml on day 11. Chest CT findings showed the thickening of the interlobular septa, bilateral pleural effusion, and swelling of mediastinal lymph nodes, symptoms which were very similar to those associated with lymphangitis carcinomatosis. She received steroid pulse therapy (methylprednisolone, 1,000 mg/day for three days). This resulted in a rapid improvement of her dyspnea and disappearance of the lymphatic blockade-mediated pulmonary findings in two days. A cervical lymph node biopsy was performed on day 12, and revealed that she had subacute lymphadenitis (Kikuchi disease). This case suggests that acute respiratory failure should be considered in cases of Kikuchi disease when associated with a lymphatic blockade.
A 27-year-old man was admitted to our hospital with the complaint of general fatigue. He had cervical and mediastinal lymphadenopathy. Laboratory examination revealed anemia, hypergammaglobulinemia, and increased levels of C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR). A chest radiograph showed opacities in both lung fields. Pathological findings from thoracoscopic mediastinal lymph node and lung biopsies were compatible with multicentric Castleman's disease (MCD), plasma cell type with pulmonary involvement. Chemotherapy combined with radiation therapy resulted in no improvement of his lymphadenopathy and inflammatory symptoms. Eight mg/kg humanized anti-human IL-6 receptor antibody (tocilitumab) was thus administered biweekly. Soon after initiating the tocilitumab treatment, the patient's general fatigue disappeared, and anemia, CRP, ESR, hypergammaglobulinemia and lymphadenopathy all improved remarkably. Further treatment with tocilitumab for two years resulted in maintenance of this good response without any severe adverse events, but the pulmonary findings showed no obvious improvement. Tocilitumab therapy was effective in this MCD patient, however its influence on concurrent lung disease needs to be investigated further.