Interleukin-2 induces NF-kappaB activation through BCL10 and affects its subcellular localization in natural killer lymphoma cells.

Deregulation of nuclear factor (NF)-kappaB signalling is common in cancers and is essential for tumourigenesis. Constitutive NF-kappaB activation in extranodal natural killer (NK)-cell lymphoma, nasal type (ENKL) is known to be associated with aberrant nuclear translocation of BCL10. Here we investigated the mechanisms leading to NF-kappaB activation and BCL10 nuclear localization in ENKLs.

Successful treatment of KIT D816V-positive, imatinib-resistant systemic mastocytosis with interferon-alpha.

We describe a case of systemic mastocytosis associated with myelodysplastic syndrome. The bone marrow showed multifocal clusters of mast cells and myeloid dysplasia. Sequencing of the KIT DNA revealed a point mutation at codon 816 including a substitution of valine for aspartic acid (D816V).

Frequent concomitant epigenetic silencing of the stress-responsive tumor suppressor gene CADM1, and its interacting partner DAL-1 in nasal NK/T-cell lymphoma.

Nasal NK/T-cell lymphoma (NL) is a rare but clinically important entity of lymphoma. Its preferential incidence in Orientals but not Caucasians suggests possible genetic predisposition. 11q deletion is common in NL, indicating certain tumor suppressor genes (TSGs) at this locus involved in its pathogenesis.

Cell death by bortezomib-induced mitotic catastrophe in natural killer lymphoma cells.

The proteasome inhibitor bortezomib (PS-341/Velcade) is used for the treatment of relapsed and refractory multiple myeloma and mantle-cell lymphoma. We recently reported its therapeutic potential against natural killer (NK)-cell neoplasms. Here, we investigated the molecular mechanisms of bortezomib-induced cell death in NK lymphoma cells.

Plasmacytoid dendritic cell leukemia with potent antigen-presenting ability.

We report 2 patients with plasmacytoid dendritic cell leukemia (pDCL) expressing CD4, CD56, CD33, CD36, HLA-DR, CD123, CD86 and CD83 in the absence of lineage markers (myeloid, B, T or natural killer cells) except for CD33. Culturing leukemic blasts of both cases with IL-3 for 4 days increased the expression of surface molecules associated with antigen presentation, e.g.

Sensitive measurement of fragmented red cell population using flow cytometry, and its application for estimating thrombotic microangiopathy after stem cell transplantation.

Background: Thrombotic microangiopathy (TMA) is one of the lethal complications after hematopoietic stem cell transplantation (SCT). The levels of fragmented red cells (FRCs), thrombomodulin (TM), and factor VIII-related antigen in the blood are the most important markers for estimating TMA. However, the FRC level has been measured by using microscopy and the naked eye; therefore, an improvement in technology to objectively count FRC is necessary.

Physiological oxidants induce apoptosis and cell cycle arrest in a multidrug-resistant natural killer cell line, NK-YS.

Natural-killer (NK) cell-derived malignant tumors, such as angiocentric lymphoma, is often resistant to various chemotherapeutic agents and follows an aggressive clinical course. We report the effects of physiological oxidants (hydrogen peroxide, H2O2; sodium hypochlorite, NaOCl and monochloramine, NH2Cl) on the cell growth and cell death in a multidrug-resistant NK tumor cell line, NK-YS. Among the oxidants tested, NH2Cl was most cytotoxic, in which more than 90% of the cells died at 150 nmol/1 x 10(6) cells.

Long-term production of pre-existing alloantibodies to E and c after allogenic BMT in a patient with aplastic anemia resulting in delayed hemolytic anemia.

Background: Delayed hemolysis mediated by long-term production of pre-existing recipient-derived antibodies directed against donor RBC antigens after allogenic BMT is an unusual complication of hematopoietic transplantation.

Case Report: A 26-year-old man with aplastic anemia had pre-existing alloantibodies to E and c. He received BMT from a donor, whose Rh phenotype was E+, c+.

Fc epsilon RI and CD22 mRNA are expressed in early B-lineage and myeloid leukemia cell lines.

CD22, one of the important markers for diagnosing B-lineage acute leukemia, was expressed in mature basophil granulocytes. We then investigated the expression of CD22 and other B cell- and basophil-related molecules in 25 human acute leukemia cell lines to find the phenotype of the virtual common progenitor of B and myeloid lineage. Surface and cytoplasmic expressions of antigens were analyzed using a flow cytometer and an essential antibody panel used for diagnosing acute leukemia as well as cytokine receptors and basophil-related enzymes.

Gene silencing of the tyrosine phosphatase SHP1 gene by aberrant methylation in leukemias/lymphomas.

High-frequent silencing of hematopoietic cell-specific protein-tyrosine phosphatase SHP1 gene by promoter methylation was detected in various kinds of leukemias and lymphomas, as well as in many hematopoietic cell lines, which is supported by our previous observation of strong decrease of SHP1 mRNA and protein. The promoter methylation of the SHP1 gene was clearly correlated with the clinical stage. Loss of heterozygosity with microsatellite markers near the SHP1 gene was shown in 79% of informative acute lymphoblastic leukemia cases.

Induction and characterization of cutaneous lymphocyte antigen on natural killer cells.

Cutaneous lymphocyte antigen (CLA) has been reported to be expressed mainly by memory/effector T lymphocytes infiltrating inflammatory skin lesions and cutaneous T-cell lymphoma. It has been suggested that CLA is a specific homing receptor, facilitating the T-cell migration into skin lesions, and also an indicator of the skin-homing T-cell subset. In the present study, we investigated the expression of CLA in natural killer (NK) cells defined phenotypically as surface CD3- and CD56+ cells in peripheral blood.

Expression of cutaneous lymphocyte antigen is associated with a poor outcome of nasal-type natural killer-cell lymphoma.

Nasal and nasal-type natural killer (NK) lymphoma is a distinct clinicopathological entity mostly associated with Epstein-Barr virus. Cases that have widespread lesions are resistant to ordinary anti-cancer therapy and take a highly aggressive course. To date, there are no available data on the relationships between the localization, clinical outcome and expression of adhesion molecules in such cases.

Cutaneous lymphoblastic lymphoma of putative plasmacytoid dendritic cell-precursor origin: two cases.

Although the neoplasm of relatively mature type plasmacytoid dendritic cells (pDC) was recently reported, that of pDC-precursor has not yet been defined. We experienced two elderly male Japanese patients with reddish skin tumors. The histology of the tumors in both patients showed terminal deoxinucleotidyl transferase (TdT)-positive lymphoblastic lymphoma (LBL).

CD56+, NKp46+ cell line (MZ93) expressing T-cell and myeloid antigens.

The MZ93 cell line, established from a patient with CML, expressed CD4, CD7, CD13, CD25, CD33, CD34, CD56 and NKp46. The additional karyotype abnormality of the Ph-positive leukemia cells in vivo, 6p+, was also observed in MZ93. The early passages of MZ93 expressed CD3 in the cytoplasm, but the late passages did not.

Acute T-lymphoblastic leukemia relapsed with the character of myeloid/natural killer cell precursor phenotype: a case report.

The leukemic lymphoblasts of a patient expressed CD7, CD13, CD33, CD34, HLA-DR and cytoplasmic CD3varepsilon. He was diagnosed with acute lymphoblastic leukemia (ALL), and successfully treated with a conventional chemotherapy for ALL. The disease relapsed three times, and the character of the cells gradually altered, i.