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In order to investigate the mechanism of interferon-alpha (IFNalpha) action in the treatment of chronic myelogenous leukemia (CML), we examined surface expressions of both type I interferon receptor 1 (IFNAR1) and 2 (IFNAR2) subunits on CD34-positive cells in bone marrow (BM) in a total of 57 CML patients. Initial cell-surface IFNAR2 expression at diagnosis assessed by flow cytometry widely distributed but showed overall significantly higher expression in CML patients when compared with normal controls. In 15 fresh patients who subsequently received IFNalpha therapy, IFNAR2 expression at diagnosis was significantly higher in cytogenetic good responders than in poor responders. Down-regulation of IFNAR2 expression during IFNalpha therapy was observed only in good responders but not in poor responders. In addition to protein level, both initial high IFNAR2c mRNA expression level and its down-regulation during IFNalpha therapy, in purified CD34-positive cells, were also observed only in good responders. In contrast to IFNAR2, cell-surface IFNAR1 expression was generally lower than IFNAR2, and correlation between either the pretreatment level or down-regulation of IFNAR1 and clinical response was not evident. With in vitro IFNalpha stimulation, CD34-positive cells showed down-regulations of cell-surface IFNAR2, and IFNAR1 to a lesser extent, in one good-responder patient, but not in one poor-responder patient. Serum soluble interferon receptor (sIFNR) was higher in untreated CML patients than in normal controls, without any correlation with clinical response to IFNalpha. Thus, the pretreatment protein and mRNA expression levels of IFNAR2 and their down-regulations during IFNalpha therapy correlate well with IFNalpha response in CML patients., (Copyright Blackwell Munksgard 2004.)

Cyclin D1 is a positive-regulator of the cell cycle and is overexpressed in myeloma cells with t(11;14)(q13;q32). First, we analyzed whether there was a correlation between cyclin D1 overexpression and the presence of Ki67-positive myeloma cells in multiple myeloma (MM). Cyclin D1 overexpression was examined by competitive RT-PCR. Then we found these two markers were present independently in a given case. FISH analysis revealed that cyclin D1 over-expression was caused by t(11;14)(q13;q32) or extra copies of B-cell leukemia/lymphoma-1 (BCL-1/CCND1), and unknown mechanism without them. We compared the gene expression between myeloma cells with cyclin D1 overexpression and those without it using cDNA microarray analysis. Analysis of the expression profiles showed that the significantly up-regulated genes included cyclin D1, cell division cycle 37 (CDC37) and B-cell leukemia/lymphoma-2 (BCL-2), while the down-regulated genes included cyclin D2 and CD9 antigen (p24) in MM cases with cyclin D1 overexpression. However, hierarchical clustering analysis of the data showed that myeloma cells of MM cases with cyclin D1 overexpression could not be distinguished clearly from those without it. Real-time RT-PCR showed that the expression of CDC37 gene was significantly up-regulated in MM patients with cyclin D1 overexpression compared with those without it (p=0.0418). However, there was no significant difference in BCL-2 gene (p=0.5748). These results suggested that MM cases with cyclin D1 overexpression do not constitute a specific group, and cyclin D1 overexpression may not be caused only by abnormality of the BCL-1/CCND1 gene. The CDC37 may collaborate with cyclin D1 in progression of MM.

CD27 is a marker of memory B cells and its interaction with its ligand, CD70, is very important for differentiation into plasma cells. Although CD27 is detected on normal plasma cells, its expression is significantly reduced with the progression of multiple myeloma (MM), including monoclonal gammopathy of undetermined significance (MGUS). CD27+ myeloma cells are thought to represent an early phase of myeloma, as CD27+ plasma cells from MM patients were found to be composed of normal plasma cells (CD19+/CD38++) and myeloma cells (CD19-/CD38++), and monoclonality was detected in the CD27+/CD38++ fraction. Given that the lack of CD27 on plasma cells is related to myelomagenesis and that the pro-apoptotic protein Siva is thought to bind to the cytoplasmic tail of CD27, we analysed alterations of cell growth and genes caused by co-culturing CD27-transfected myeloma cell lines (U266, KMS-5) with CD70-transfected NIH3T3 cells. CD27-CD70 interaction could not induce apoptosis in either type of myeloma transfectant, and binding between Siva and CD27 was not detected. cDNA microarray (human apoptosis CHIP) analysis showed a significant upregulation of expression of the ectodermal neural cortex 1 (ENC1) gene by CD27-CD70 interaction compared with CD27 transfection alone. These findings show that the relationship between the loss of CD27 and oncogenesis of plasma cells is not simple. It remains unclear whether the lack of CD27 leads to evasion of apoptosis.

Type 2B von Willebrand disease (vWD) is a von Willebrand factor (vWF) subtype with increased binding affinity for platelet glycoprotein (GP) Ib and is characterized by increased ristocetin-induced platelet agglutination at low concentrations of ristocetin. Usually there are no high molecular weight multimers of vWF, and platelet counts are within normal ranges in patients with type 2B vWD. We identified a variant of type 2B vWD showing the full range of vWF multimers in plasma accompanied by thrombocytopenia, which seemed to be caused by circulating platelet aggregation. Since the A1 domain and surrounding region of vWF alleles, in which mutation sites are known to be clustered in type 2B vWD, appeared normal on nucleotide sequencing, this increased binding affinity of vWF for GPIb may be due to a novel mechanism differing from that which usually underlies type 2B vWD.

Peripheral T cell neoplasms originating from gamma/delta T cells are rarely reported, despite the development of hepatosplenic lymphoma from gamma/delta T cells. We report a case of multiple generated gamma/delta T cell lymphomas presenting in the subcutaneous tissue and small intestine in a patient with accompanying capillary leak syndrome. The patient, a 43-year-old male presented with remarkable systemic edema, pleural effusion, and ascites. Widespread tumors were evident in the subcutaneous tissue and in the small intestine. A biopsy revealed anaplastic large cell lymphoma in these lesions. Phenotypic examination showed that the neoplastic cells were positive for the surface markers CD3 and TCR delta, but negative for CD4, CD8 and TCR beta. Genomic analysis revealed a clonal rearrangement of the TCR genes encoding the gamma, delta, and beta chains. A polymerase chain reaction analysis of the gene encoding the TCR delta chain showed that the rearrangement occurred between V delta 3 and J delta 1, suggesting that neoplastic cells were generated in the early stages of T cell differentiation.

We encountered a male patient with marked basophilia and eosinophilia complicated by anemia, thrombocytopenia, myelofibrosis, and hyperhistaminemia. Since morphological abnormalities were unclear and since chromosome analysis showed 45,XY,-7, a diagnosis of basophilic-eosinophilic myeloproliferative disorder was made. After administration of prednisolone and cytarabine ocfosfate, basophil and eosinophil levels decreased, but blasts transiently appeared in the peripheral blood. Chromosome analysis performed at the time of appearance of blasts showed a clone with 45,XY,-7,del(16)(q22). Subsequently, pancytopenia developed, after which white blood cell count and its classification were normal, as were chromosome findings. In this patient, monosomy 7 seemed to have induced myeloproliferative disorder with basophilia and eosinophilia, and del(16)(q22) may have enhanced the eosinophilia.

Follicular lymphoma is a low grade malignant lymphoma. However, some follicular lymphomas undergo histological transformation into higher grade malignant lymphomas. We recently encountered a diffuse large cell lymphoma which seemed to have progressed from a follicular lymphoma and which finally transformed into a small non-cleaved lymphoma. Each stage of the histological transformation was accompanied by increasing clinical grades of malignancy. It was suspected that in our patient a follicular lymphoma initially developed due to rearrangement of the BCL2 gene, and then underwent histological transformation into a diffuse large cell lymphoma, which was associated with p53 mutation. Subsequent rearrangement of C-MYC promoted the histological transformation of this diffuse large cell lymphoma into a small non-cleaved lymphoma. Our findings indicate that p53 mutation and rearrangement of C-MYC are involved in the histological transformation of follicular lymphomas into more advanced lymphomas.

A 26-year-old male patient with pachydermoperiostosis is reported. He had severe anemia with myelofibrosis. Treatment with iron, prednisolone, oxymethorone and 1 alpha (OH)D3 were not satisfactory. But steroid pulse therapy with parenteral iron improved his anemia and pancytopenia, but was not sufficient to relieve the bone marrow fibrosis or splenomegaly. The mechanism of anemia which was considered to be multifactorial including gastro-intestinal bleeding associated with peptic ulcer or erosion and bone marrow failure due to myelofibrosis, is discussed.

Two kindreds of phosphofructokinase (PFK) deficiency associated with congenital nonspherocytic hemolytic anemia and mild myopathy were found in Japan. Both probands had jaundice, gallstones, and slight to moderate degree of exercise intolerance. They showed decreased level of red cell PFK activity and no increase of blood lactate in forearm ischemic exercise test. We studied these probands' red cell PFKs by partial purification and condensation. Muscle type isozyme of PFK in both cases was not demonstrable in starch gel electrophoresis and DEAE-Sephadex chromatography. The clinical symptoms are considered to be due to a defect of muscle type isozyme.

Enzymatic and electron microscopical studies were performed on the muscle of a proband with phosphofructokinase deficiency. Enzymatic studies showed that muscle phosphofructokinase activity of the proband was decreased to about a half of normal. This enzyme was quite thermolabile and had low affinity for fructose 6-phosphate. Electron microscopical studies showed the accumulation of glycogen granules beneath the sarcolemma and between the myofibrils in spite of a lack of accumulation of the intermediates before the step of phosphofructokinase. The proband's clinical symptoms, i.e., hemolytic anemia and myopathy, were considered to be due to the unstable, mutant, muscle-type phosphofructokinase in the red blood cells and muscle.

The concordance rate for diagnoses of atomic bomb-related cases of leukemia in Nagasaki was determined using the French-American-British (FAB) classification for acute leukemias and myelodysplastic syndromes (MDS). Two Radiation Effects Research Foundation (RERF) hematologists and one of the members (JMB) of the FAB cooperative group reviewed independently the peripheral blood and/or bone marrow smears from 193 people with leukemia or a related disorder. There was 85% agreement in the identification of types and subtypes of acute leukemia. There was almost complete agreement for the diagnoses of non-FAB disorders (chronic myeloid leukemia (CML), adult T-cell leukemia (ATL) and others) resulting in overall concordance of 88.2%. The present study suggests that the previously established leukemia types for about a quarter of the cases of acute leukemia and related disorders except CML should be changed. Considerable numbers of cases of ATL and MDS were involved in this series. The frequency of the former disease was not high in the high-dose irradiated group, but that of the latter was considerably high. All subtypes of AML except M3 and M6 were present in the high-dose group. The striking difference in CML incidence between Nagasaki and Hiroshima may continue to be a problem in relation to biological response to radiation exposure.