[Long-term complete remission of HIV-negative primary testicular plasmablastic lymphoma treated with bortezomib in combination with EPOCH].

Plasmablastic lymphoma (PBL) is a rare variant of diffuse large B-cell lymphoma that is frequently associated with HIV infection or other immunodeficiencies. We present a case of HIV-negative primary testicular PBL with long-term complete remission (CR) and successful treatment with bortezomib in combination with EPOCH (V-EPOCH). Because of rapidly increasing right testicular swelling, an 86-year-old man without immunodeficiencies was admitted to our hospital. Following that, a right high orchiectomy was performed. Histopathological and immunohistochemical analyses revealed diffuse infiltration of plasmablastic lymphocytes, which were positive for CD38, CD138, CD56, MUM1, lambda, EBER, and MYC respectively, but negative for CD20. The MIB-1 index was 90%. FDG abnormal uptake was discovered on PET/CT at systemic lymph nodes. There was no abnormal cell infiltration in either the bone marrow or cerebral spinal fluid. He was diagnosed with PBL, clinical-stage IIIE-A, IPI high-intermediate risk. He achieved durable CR more than 30 months after the diagnosis after six courses of V-EPOCH, followed by intrathecal prophylaxis (IT) and adjuvant radiation therapy (total 30 Gy). Although PBL shows an aggressive clinical course and poor prognosis, adequate therapeutic approaches for PBL have not been established due to the rarity of this disease. According to our findings, V-EPOCH combined with IT and adjuvant radiotherapy appeared to be feasible and effective as a frontline treatment for elderly patients with primary testicular PBL.

[Durable remission attained with rituximab therapy in a patient with acquired von Willebrand syndrome associated with CD20-positive lymphoproliferative disorder].

A 61-year-old female with no history of bleeding was admitted to our hospital owing to persistent bleeding after the left knee joint injection and activated partial thromboplastin time prolongation. Subsequent coagulation tests revealed a critically declined level of the von Willebrand factor (VWF) antigen (<10%) and activity (<10%) measurement besides a significantly declined factor VIII activity (4%). Despite diagnosing her with acquired von Willebrand syndrome (AvWS) and managing her bleeding with desmopressin acetate hydrate (DDAVP), we could not precisely make a definitive diagnosis the underlying disorder. More than 15 months after the onset of AvWS, CD20-positive atypical lymphocytes appeared in the peripheral blood and bone marrow without systemic lymphadenopathy. We initiated rituximab monotherapy eight times a week for CD20-positive lymphoproliferative disorders. The treatment not only caused the disappearance of the clonal expansion of CD20-positive atypical lymphocytes in both peripheral blood and bone marrow but also exhibited the clinical remission of AvWS. In addition, the maintenance therapy with rituximab every 3 months resulted in the durable remission of over 5 years. AvWS is a rare bleeding disorder, similar to von Willebrand disease, which arises from various underlying diseases. Our experience with this case highlights that rituximab proved to be one of the effective and well-tolerated treatment options for AvWS associated with CD20-positive B-cell lymphoproliferative disorders.

Hypoxia-inducible microRNA-210 regulates the DIMT1-IRF4 oncogenic axis in multiple myeloma.

Multiple myeloma (MM) is characterized by the accumulation of a population of malignant plasma cells within the bone marrow and its microenvironment. A hypoxic niche is located within the microenvironment, which causes myeloma cells to become quiescent, anti-apoptotic, glycolytic, and immature. Cell heterogeneity may be related to distinct gene expression profiles under hypoxic and normoxic conditions. During hypoxia, myeloma cells acquire these phenotypes by downregulating interferon regulatory factor 4 (IRF4), an essential transcription factor in myeloma oncogenesis. To identify essential microRNAs and their targets regulated under hypoxic conditions, we undertook microRNA and cDNA microarray analyses using hypoxia-exposed primary MM samples and myeloma cell lines. Under hypoxia, only miR-210 was highly upregulated and was accompanied by direct downregulation of an 18S rRNA base methyltransferase, DIMT1. This inverse expression correlation was validated by quantitative RT-PCR for primary MM samples. We further determined that DIMT1 has an oncogenic potential as its knockdown reduced tumorigenicity of myeloma cells through regulation of IRF4 expression. Notably, by analyzing gene expression omnibus datasets in the National Center for Biotechnology Information database, we found that DIMT1 expression increased gradually with MM progression. In summary, by screening for targets of hypoxia-inducible microRNA-210, we identified DIMT1 as a novel diagnostic marker and therapeutic target for all molecular subtypes of MM.

Varicella-zoster virus-associated fulminant hepatitis following allogeneic hematopoietic stem cell transplantation for multiple myeloma.

Disseminated visceral varicella-zoster virus (VZV) infection rarely occurs in recipients of allogeneic hematopoietic stem cell transplantation (allo-HSCT). To date, only a few cases of isolated VZV-induced fulminant hepatitis following allo-HSCT have been reported. We herein describe the case of a 47-year-old Japanese man with multiple myeloma who developed fulminant hepatitis 17 months after undergoing allo-HSCT. Despite receiving fresh frozen plasma and platelet transfusions, he developed a bleeding tendency (systemic purpura, petechiae and oral bleeding), slipped into a coma and eventually died. He was retrospectively diagnosed with viscerally disseminated VZV infection based on a postmortem examination and multiplex polymerase chain reaction (PCR) amplification.

Late-onset fatal Epstein-Barr virus-associated hemophagocytic syndrome following cord blood cell transplantation for adult acute lymphoblastic leukemia.

A 43-year-old Japanese woman underwent unrelated cord blood transplantation (CBT) during remission for acute lymphoblastic leukemia with t(4; 11)(q21;q23). Tacrolimus was given for prophylaxis of graft-versus-host disease. The posttransplantation clinical course was mostly uneventful, and the leukemia remained in remission. Fourteen months after CBT, the patient developed pancytopenia and hepatic dysfunction with persistent high-grade fever. The bone marrow was hypocellular with increased numbers of macrophages and hemophagocytes. The numbers of Epstein-Barr virus (EBV) copies in peripheral blood samples were remarkably high. Although the patient showed complete donor-type hematopoiesis, the titer of viral capsid antigen immunoglobulin G was low, and the results of a test for EBV nuclear antigen were negative. There was no clinical response to the reduction of immunosuppressive therapy or to the administration of high-dose methylprednisolone, human immunoglobulin, or acyclovir. The patient died 466 days after CBT of massive gastrointestinal hemorrhage due to bone marrow and hepatic failures. This case demonstrates that fatal EBV-associated hemophagocytic syndrome (HPS) can occur more than 1 year after CBT. This report is the first of a case of late-onset EBV-associated HPS following CBT.

Successful autologous peripheral blood stem cell transplantation using thiotepa in a patient with systemic sclerosis and cardiac involvement.

A 19-year-old man with systemic sclerosis (SSc) was hospitalized for autologous peripheral blood stem cell transplantation (auto-PBSCT) due to progressive scleroderma and cardiac involvement despite conventional treatment. During the administration of cyclophosphamide (60 mg/kg/day for 2 days) for mobilization and collection of CD34+ selected peripheral blood stem cells, he developed congestive heart failure. Echocardiogram showed hypokinetic asynergy from the septum to posterior wall, which might indicate underlying cardiac damage. We were also concerned about the risk of high-dose cyclophosphamide-induced cardiotoxicity. Since the dose-limiting toxicity of thiotepa, an alkylating agent, is myelosuppression, and cardiac toxicity due to thiotepa is less common, we used a conditioning regimen consisting of thiotepa (10 mg/kg/day, day -5) and low-dose cyclophosphamide (50 mg/kg/day, days -3 and -2), instead of the conventional high-dose cyclophosphamide (50 mg/kg/day x 4 days/course). The post-transplant course was uneventful, and the modified Rodnan skin thickness score improved from 32 to 15. The present case report demonstrates that thiotepa can be employed as a conditioning regimen for auto-PBSCT in SSc patients with cardiac involvement in order to reduce cyclophosphamide-induced cardiotoxicity.

Successful reduced-intensity hematopoietic stem cell transplantation in myelodysplastic syndrome with severe coronary artery disease.

A 60-year-old Japanese man with myelodysplastic syndrome (MDS) and effort angina was referred to our clinic for treatment of MDS. The patient was transfusion-dependent and displayed coronary artery disease (CAD) with 99% obstruction of the left anterior descending coronary artery. Treatment comprised reduced-intensity hematopoietic stem cell transplantation with administration of fludarabine phosphate (180 mg/m(2)) and busulfan (8 mg/kg), followed by allogeneic peripheral blood stem cell transplantation from an HLA-matched sister. The regimen was well tolerated, and engraftment occurred rapidly without any therapy-related complications, including cardiovascular attack. Sex chromosome analysis by fluorescence in situ hybridization revealed complete donor chimerism on day 29 for bone marrow cells and on day 59 for peripheral blood leukocytes. The patient became transfusion-independent on posttransplantation day 8. As of 22 months postoperatively, he remains well, with 100% Karnofsky performance status, a limited type of chronic graft-versus-host disease, and no recurrence of disease. The clinical course of the patient suggests that this preparative regimen allows safe allogeneic stem cell transplantation for MDS patients with severe CAD.

Phagocytosis of codeveloping megakaryocytic progenitors by dendritic cells in culture with thrombopoietin and tumor necrosis factor-alpha and its possible role in hemophagocytic syndrome.

Tumor necrosis factor-alpha (TNF-alpha) and thrombopoietin (TPO) have been shown to induce the differentiation and proliferation of CD34+ cells toward dendritic cells (DCs) in the presence of multiacting cytokines. We hypothesized that the costimulation of TPO and TNF-alpha generates megakaryocytic progenitors and DCs together from human CD34+ cells and that the interaction of these cells may indicate a physiologic and/or a pathologic role of DCs in megakaryopoiesis. When highly purified human CD34+ cells were cultured for 7 days with TPO alone, the generated cells expressed megakaryocytic markers, such as CD41, CD42b, and CD61. The addition of TNF-alpha with TPO remarkably decreased the number of megakaryocytic progenitor cells without affecting the cell yield. Almost half of the cells thus generated expressed CD11c, and most of them were positive for CD4 and CD123. Furthermore, CD11c+ cells were found to capture damaged CD61+ cells and to induce autologous T-cell proliferation, although the cytokine productions were low. We also confirmed an engulfment of CD61+ cells and their fragment by CD11c+ cells in bone marrow cells from patients with hemophagocytic syndrome. These findings suggest that DCs generated under megakaryocytic and inflammatory stimuli are involved in megakaryopoiesis and the subsequent immune responses to self-antigens.

Allogeneic haematopoietic stem cell transplantation as a promising treatment for natural killer-cell neoplasms.

The efficacy of allogeneic haematopoietic stem-cell transplantation (allo-HSCT) for natural killer (NK)-cell neoplasms is unknown. We investigated the results of allo-HSCT for NK-cell neoplasms between 1990 and 2003 through questionnaires. After reclassification by a haematopathologist, of 345 patients who underwent allo-HSCT for malignant lymphoma, 28 had NK-cell neoplasms (World Health Organization classification): extranodal NK/T-cell lymphoma (n=22), blastic NK-cell lymphoma (n=3), and aggressive NK-cell leukaemia (n=3). Twelve were chemosensitive and 16 chemorefractory. Twenty-two had matched-related donors. Stem-cell source was bone marrow in eight and mobilised peripheral blood in 20. Conditioning regimens were myeloablative (n=23) and non-myeloablative (n=5). Grade 2-4 acute graft-versus-host disease (GVHD) and chronic GVHD developed in 12 and 8 respectively. Eight died of disease progression, three of infection, two of acute GVHD, one of veno-occlusive disease, one of interstitial pneumonitis, and one of thrombotic microangiopathy. Two-year progression-free and overall survivals were 34% and 40% respectively (median follow-up, 34 months). All patients who did not relapse/progress within 10 months achieved progression-free survival (PFS) during the follow-up. In multivariate analysis, stem cell source (BM versus peripheral blood; relative risk 3.03), age (>or=40 years vs. <40 years; relative risk 2.85), and diagnoses (extranodal NK/T-cell lymphoma versus others; relative risk 3.94) significantly affected PFS. Allo-HSCT is a promising treatment for NK-cell neoplasms.

Fluorescence in situ hybridization monitoring of BCR-ABL-positive neutrophils in chronic-phase chronic myeloid leukemia patients during the primary stage of imatinib mesylate therapy.

We describe a method for monitoring chronic myeloid leukemia (CML) patients treated with imatinib that uses fluorescence in situ hybridization (FISH) to detect BCR-ABL in peripheral blood (PB) granulocytes. First, we compared this method, termed Neutrophil-FISH, with interphase FISH (i-FISH) analysis of bone marrow (BM), i-FISH analysis of PB mononuclear cells, and conventional cytogenetic analysis (CCA) of BM in 30 consecutive CML patients. We found the percentage of BCR-ABL-positive neutrophils as determined by Neutrophil-FISH to correlate best with the percentage of Philadelphia chromosome-positive metaphases in the BM determined by CCA (y = 0.8818x + 5.7249; r(2) = 0.968). We then performed a serial Neutrophil-FISH study of 10 chronic-phase CML patients treated with imatinib and found that the technique could clearly separate imatinib responders from nonresponders within 12 weeks of drug administration. There was a significant difference in the percentages of BCR-ABL-positive neutrophils between responder (mean 3 SD, 18.2% 3 11.8%) and nonresponder (82.4% 3 5.1%) groups at 12 weeks (P < .0001, Student t test).Together with real-time quantitative polymerase chain reaction analysis, Neutrophil-FISH represents another useful method for monitoring CML patients during the primary myelosuppressive stage of imatinib therapy because it is a quick, simple, and reliable method for assessing cytogenetic response.

Gene expression profiling of human erythroid progenitors by micro-serial analysis of gene expression.

We compared the expression profiles of highly purified human CD34+ cells and erythroid progenitor cells by micro-serial analysis of gene expression (microSAGE). Human CD34+ cells were purified from granulocyte colony-stimulating factor-mobilized blood stem cells, and erythroid progenitors were obtained by cultivating these cells in the presence of stem cell factor, interleukin 3, and erythropoietin. Our 10,202 SAGE tags allowed us to identify 1354 different transcripts appearing more than once. Erythroid progenitor cells showed increased expression of LRBA, EEF1A1, HSPCA, PILRB, RANBP1, NACA, and SMURF. Overexpression of HSPCA was confirmed by real-time polymerase chain reaction analysis. MicroSAGE revealed an unexpected preferential expression of several genes in erythroid progenitor cells in addition to the known functional genes, including hemoglobins. Our results provide reference data for future studies of gene expression in various hematopoietic disorders, including myelodysplastic syndrome and leukemia.

Codevelopment of dendritic cells along with erythroid differentiation from human CD34(+) cells by tumor necrosis factor-alpha.

OBJECTIVE: Tumor necrosis factor-alpha (TNF-alpha) inhibits erythropoiesis and enhances nonerythroid colony formation. The present study examines the nature of these nonerythroid cells and investigates their physiologic role in relation to erythroid progenitor cells. MATERIALS AND METHODS: Highly purified human CD34(+) cells underwent erythroid differentiation in the presence of multiple cytokines, including stem cell factor (SCF), interleukin-3 (IL-3), and erythropoietin (EPO), with and without TNF-alpha. We enumerate colony-forming unit-erythroid (CFU-E) and glycophorin A (GPA; a specific marker for erythroid lineage) positive cells in semisolid phase as well as in liquid suspension culture. The character and roles of codeveloping nonerythroid cells in the presence of TNF-alpha were analyzed using fluorescent activating cell sorter, enzyme immunohistochemistry, and confocal microscopy. RESULTS: TNF-alpha inhibited the generation of GPA(+) cells and conversely enhanced the generation of GPA(-) cells. The GPA(-) cells were comprised of cells with excentric cell shape and were positive for HLA class I, HLA class II, CD1a, CD4, CD11c, CD14, CD40, CD80, CD83, and CD86, but not for CD3, CD8, CD19, CD20, and CD56, indicating the codevelopment of dendritic cells (DC) along with erythroid differentiation. Developing DC/DC precursors were detected within 3 days of culture. Only in the presence of TNF-alpha did CD34(+) cells proliferate by forming aggregates where both GPA(+) and CD11c(+) DC/DC precursors were present. During culture period, immature CD11c(+) DC were capable of endocytosing damaged GPA(+) cells. CONCLUSIONS: GPA(-) cells cogenerated from human CD34(+) cells during erythroid differentiation in the presence of IL-3/SCF/EPO and TNF-alpha express DC phenotypes. The CD11c(+) DC subset physically and selectively associates with developing immature erythroid cells and damaged self-GPA(+) cells and then obtains and captures self-substances.

[Hemolytic uremic syndrome-like episode following nonmyeloablative hematopoietic stem cell transplantation in a patient with chronic myeloid leukemia].

We report on a 61-year-old woman with chronic myeloid leukemia (CML) who developed a hemolytic uremic syndrome (HUS)-like episode following nonmyeloablative allogeneic hematopoietic stem cell transplantation. Macrohematuria, hypertension, hemolytic anemia with red cell fragmentation, thrombocytopenia, and progressive renal insufficiency were observed after thawed peripheral blood stem cell (PBSC) infusion. Although transient systemic hemolysis is known to occur during dimethylsulfoxide (DMSO)-cryopreserved stem cell infusion, HUS caused by DMSO has not been described in the literature. We speculate that one of the triggers of the HUS-like episode could have been renal microangiopathy caused by the long-term administration of interferon-alpha before the stem cell transplantation.

Dysregulation of apoptosis and a novel mechanism of defective apoptotic signal transduction in human B-cell neoplasms.

Apoptotic cell death is essential for normal B-cell development and for shaping the B-cell repertoire. Dysregulation of the Bcl-2 related proteins and alterations of the p53/p14ARF pathway are implicated in the pathogenesis and treatment resistance in human B-cell malignancies. We found a novel mechanism of dysregulated apoptosis in human B lymphoma Raji cells that differs from that of altered Bcl-2 and p53 functions. This cell line was resistant to nuclear apoptosis induced by various stimuli, and neither mitochondrial activation nor activation of caspase-3 led to DNA fragmentation. DNA in purified Raji nuclei was degraded in the presence of lysates from the apoptosis-sensitive cell line HL-60, whereas Raji cell lysates did not induce DNA fragmentation in HL-60 nuclei. Cleavage of ICAD/DFF-45 was normal. These results indicate that the apoptosis signal transduction pathway is defective downstream of caspase-3 in Raji cell cytoplasm. Therefore, exploring the molecular mechanism in this system should provide insight into apoptosis resistance in human B-cell malignancies.