Autocrine and Paracrine Interactions between Multiple Myeloma Cells and Bone Marrow Stromal Cells by Growth Arrest-specific Gene 6 Cross-talk with Interleukin-6.

The pathogenesis of multiple myeloma (MM) has not yet been fully elucidated. Our microarray analysis and immunohistochemistry revealed significant up-regulation of growth arrest-specific gene 6 (Gas6), a vitamin K-dependent protein with a structural homology with protein S, in bone marrow (BM) cells of MM patients. ELISA showed that the serum levels of soluble Gas6 were significantly increased in the MM patients when compared with healthy controls. Gas6 was overexpressed in the human CD138-positive MM cell line RPMI-8226. Exogenous Gas6 suppressed apoptosis induced by serum deprivation and enhanced cell proliferation of the MM cells. The conditional medium from the human BM stromal cell line HS-5 induced cell proliferation and anti-apoptosis of the MM cells with extracellular signal-regulated kinase, Akt, and nuclear factor-κB phosphorylation, which were reversed by the neutralizing antibody to Gas6 or IL-6. The TAM family receptor Mer, which has been identified as a Gas6 receptor, was overexpressed in BM cells of MM patients. The knockdown of Mer by siRNA inhibited cell proliferation, anti-apoptosis, and up-regulation of intercellular cell adhesion molecule-1 (ICAM-1) in MM cells stimulated by an HS-5 cell-conditioned medium. Furthermore, the Gas6-neutralizing antibody reduced the up-regulation of IL-6 and ICAM-1 induced by a HS-5 cell-conditioned medium in MM cells. The present study provides new evidence that autocrine and paracrine stimulation of Gas6 in concert with IL-6 contributes to the pathogenesis of MM, suggesting that Gas6-Mer-related signaling pathways may be a promising novel target for treating MM.

[Airway obstruction due to localized tracheal lesion of extranodal NK/T-cell lymphoma, nasal type].

A 76-year-old man presented with a tracheal tumor associated with severe respiratory obstruction. A tracheotomy was performed due to respiratory failure. F-fluorodeoxyglucose (FDG) -positron emission tomography/computed tomography revealed an abnormal accumulation of FDG (maximum standardized uptake value: 16) in the trachea. A histopathological examination of the tracheal biopsy revealed extranodal NK/T-cell lymphoma, nasal type (ENKL). He was treated with concurrent radiotherapy (50 Gy) for the tracheal tumor and three courses of two-thirds dose ofdexamethasone, etoposide, ifosfamide, and carboplatin. Although the tumor responded remarkably well to this therapy, the patient died of an ENKL recurrence in the lungs and liver 11 months post therapy.

A possible role of low regulatory T cells in anti-acetylcholine receptor antibody positive myasthenia gravis after bone marrow transplantation.

BACKGROUND: Chronic graft-versus-host disease (GVHD) appears several months following allogenic hematopoietic stem cell transplantation (HSCT) and is clinically analogous to autoimmune disorder. Polymyositis is a common neuromuscular disorder in chronic GVHD, but myasthenia gravis (MG) is extremely rare. Hence, its pathophysiology and treatment have not been elucidated. CASE PRESENTATION: A 63-year-old man with a history of chronic GVHD presented with ptosis, dropped head, and dyspnea on exertion, which had worsened over the previous several months. He showed progressive decrement of compound muscle action potential in the deltoid muscle evoked by 3-Hz repetitive nerve stimulation, a positive edrophonium test, and elevated levels of serum anti-acetylcholine receptor antibodies, which suggested a diagnosis of generalized MG. No thymoma was found. Flow cytometric analysis revealed a remarkable depletion of peripheral Tregs (CD4+CD25highFOXP3+ cells, 0.24% of the total lymphocytes). Administration of prednisolone and tacrolimus was insufficient to alleviate his symptoms; however, the use of rituximab successfully improved his condition. CONCLUSIONS: Myasthenic symptoms appeared in the process of tapering prednisolone for the treatment of chronic GVHD, supporting the diagnosis of MG associated with chronic GVHD. The present case proposes a possibility that reduction of Tregs might contribute to the pathogenesis of MG underlying chronic GVHD. Immunotherapy with rituximab is beneficial for treatment of refractory MG and GVHD.

CD4+ T cells in aged or thymectomized recipients of allogeneic stem cell transplantations.

BACKGROUND: CD4+CD25highFOXP3+ regulatory T (Treg) cells, which include thymus-derived and peripherally induced cells, play a central role in immune regulation, and are therefore crucial to prevent graft-versus-host disease (GVHD). The increasing use of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for elderly patients with thymus regression, and our case of allo-HSCT shortly after total thymectomy, raised questions about the activity of thymus-derived Treg cells and peripherally induced Treg cells, which are otherwise indistinguishable. RESULTS: We found that despite pre-transplant thymectomy or older age, both naïve and effector Treg cells, as well as naïve and effector conventional T cells, proliferated in allo-HSCT recipients. Higher proportions of total Treg cells 1 month post allo-HSCT, and naïve Treg cells 1 year post allo-HSCT, appeared in patients achieving complete chimera without developing significant chronic GVHD, including our thymectomized patient, compared with patients who developed chronic GVHD. CONCLUSIONS: Treg cells that modulate human allogeneic immunity may arise peripherally as well as in the thymus of allo-HSCT recipients.

A Case of Acquired von Willebrand Syndrome Complicated by Acute Myelomonocytic Leukemia.

We here report a 21-year-old male who presented with acute myelomonocytic leukemia (AMML) associated with acquired von Willebrand syndrome (AVWS). To our knowledge, this is the first case of AVWS caused by AMML. In our case, following remission-induction chemotherapy combined with idarubicin and cytarabine, the patient showed remarkable improvement of bleeding symptoms due to AVWS. Moreover, after an allogeneic stem cell transplantation from a sibling donor, both AMML and AVWS maintain complete remission.

Circulating intranuclear proteins may play a role in development of disseminated intravascular coagulation in individuals with acute leukemia.

Intranuclear proteins, including high mobility group box 1 (HMGB1) and histone H3, released from inflammatory cells activate platelets and the coagulation systems, leading to development of disseminated intravascular coagulation (DIC) in individuals with sepsis. These observations prompted us to hypothesize that HMGB1 and histone H3 liberated from leukemia cells undergoing apoptosis after chemotherapy might play a role in development of DIC. To test this hypothesis, we prospectively measured plasma levels of coagulation markers and intranuclear proteins in patients with newly diagnosed acute leukemia (n = 17) before and after chemotherapy. Ten of 17 patients were diagnosed with DIC at the time of diagnosis of leukemia. Serum levels of HMGB1 and histone H3 were significantly higher in patients with DIC than in non-DIC patients. Of note, seven patients developed DIC or experienced exacerbation of coagulopathy after administration of anti-leukemic agents. Intriguingly, an increase in levels of HMGB1 and histone H3 were detected in five of seven patients. These findings suggest that intranuclear proteins spontaneously released from leukemia cells may play a role in development of leukemia-related DIC. Additionally, remission induction chemotherapy causes apoptosis of leukemia cells, leading to forced release of intranuclear proteins, which may exacerbate coagulopathy.

A critical role of the Gas6-Mer axis in endothelial dysfunction contributing to TA-TMA associated with GVHD.

Endothelial dysfunction in the early phases of hematopoietic stem cell transplantation (HSCT) contributes to a common pathology between transplant-associated thrombotic microangiopathy (TA-TMA) and graft-versus-host disease (GVHD), which are serious complications of HSCT. Growth arrest-specific (Gas) 6 structurally belongs to the family of plasma vitamin K-dependent proteins working as a cofactor for activated protein C, and has growth factor-like properties through its interaction with receptor tyrosine kinases of the TAM family: Tyro3, Axl, and Mer. Serum Gas6 levels were significantly increased in HSCT patients with grade II to IV acute GVHD (aGVHD), and Gas6 and Mer expression levels were upregulated in aGVHD lesions of the large intestine and skin. The increased serum Gas6 levels were also correlated with elevated lactate dehydrogenase, d-dimer, and plasmin inhibitor complex values in HSCT patients with aGVHD. In human umbilical vein endothelial cells (ECs), exogenous Gas6 or the exposure of sera isolated from patients with grade III aGVHD to ECs induced the downregulation of thrombomodulin and the upregulation of PAI-1, as well as the upregulation of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1, which were inhibited by UNC2250, a selective Mer tyrosine kinase inhibitor. In mouse HSCT models, we observed hepatic GVHD with hepatocellular apoptosis, necrosis, and fibrosis, as well as TA-TMA, which is characterized pathologically by thrombosis formation in the microvasculature of the liver and kidney. Of note, intravenous administration of UNC2250 markedly suppressed GVHD and TA-TMA in these mouse HSCT models. Our findings suggest that the Gas6-Mer axis is a promising target for TA-TMA after GVHD.

Intestinal Behçet disease associated with myelodysplastic syndrome accompanying trisomy 8 successfully treated with abdominal surgery followed by hematopoietic stem cell transplantation: A case report.

RATIONALE: Intestinal Behçet disease (BD) with myelodysplastic syndrome (MDS) is a rare condition that is resistant to various immunosuppressive therapies. Several cases in which hematopoietic stem cell transplantation (HSCT) was effective for intestinal BD with MDS accompanying trisomy 8 have been reported. PATIENT CONCERNS: We report an 18-year-old female with a 7-year history of BD. Colonoscopy demonstrated a huge ulcer in the cecum. Chromosomal examination revealed a karyotype of trisomy 8 in 87% of cells. Bone marrow examination revealed dysplastic cells in multilineages. DIAGNOSES: A diagnosis of intestinal BD associated with MDS accompanying trisomy 8 was made. INTERVENTIONS: The patient underwent ileocecal resection due to microperforations of ileocecal ulcers; she then underwent allogeneic peripheral blood stem cell transplantation (PBSCT) with her mother as a donor. OUTCOMES: After the PBSCT, the patient's symptoms due to BD (fever, oral aphthae, abdominal pain, and genital ulcers) completely disappeared, with no severe adverse events. LESSONS: The present case demonstrates that HSCT including PBSCT might be an effective new therapeutic option for refractory intestinal BD with MDS when immunosuppressive therapy has achieved insufficient efficacy.

Lenalidomide as a Beneficial Treatment Option for Renal Impairment Caused by Light Chain Deposition Disease.

Light chain deposition disease (LCDD) is a rare systemic disorder caused by the deposition of light chain immunoglobulins, which often results in renal impairment associated with either nephrotic syndrome or asymptomatic proteinuria. B-cell neoplasms, such as multiple myeloma and lymphoproliferative disorders, are well-known underlying diseases in LCDD. Some chemotherapy regimens have been reported, but both evidence-based treatment and management for LCDD have yet to be established. We herein report three cases of LCDD treated with lenalidomide-based therapy, resulting in hematologic responses accompanied by a significant reduction in proteinuria and improvement in the renal function. We recommend lenalidomide-based therapy for renal impairment caused by LCDD.

Microvascular thrombosis in the hepatic vein of a patient with paroxysmal nocturnal hemoglobinuria.

Paroxysmal nocturnal hemoglobinuria (PNH) is characterized by complement-mediated hemolysis, venous thrombosis, and bone marrow failure. In May 2003, a 33-year-old man was admitted to a hospital with right hypochondralgia and fever. He had a history of aplastic anemia. The patient's diagnosis of diffuse microvessel thrombosis in the hepatic vein due to an unknown cause was derived from the findings of a contrast-enhanced computed tomography examination of the abdominal region, angiographic evaluation of abdominal vessels, and pathohistologic examination of a liver biopsy sample. The patient was subsequently treated with warfarin. The abdominal pain and fever continued, however, and anemia gradually appeared. In April 2004, the patient was referred to our hospital to examine the cause of the thrombosis. On admission, slight anemia and a low serum haptoglobin level were observed. A flow cytometry evaluation of CD55 and/or CD59, CD59, and CD48 expression in erythrocytes, granulocytes, and monocytes, respectively, showed that the respective proportions of negative populations were 5.6%, 97.1%, and 96.2%. The patient then received a diagnosis of aplastic anemia/PNH syndrome, which had caused the hemolytic anemia and thrombosis, although no hemoglobinuria had been observed during his clinical course. This patient is, to our knowledge, the first reported case of a PNH patient with thrombosis present only in hepatic microvessels and not in hepatic large vessels, in spite of the presence of few hemolytic events.

Steroid-resistant autoimmune myelofibrosis in a patient with autoimmune hepatitis and Evans syndrome complicated with increased expression of TGF-ß in the bone marrow: a case report.

We here report a 47-year-old female with autoimmune myelofibrosis (AIMF) associated with liver damage caused by autoimmune hepatitis and Evans syndrome. Bone marrow biopsy revealed hypocellular marrow with grade 2 reticulin fibrosis and increased levels of B lymphocytes (CD20+), T lymphocytes (CD3+, CD8+), and plasma cells (CD138+). Immunohistochemical analysis revealed increased expression of transforming growth factor-ß (TGF-ß) in infiltrating lymphocytes and macrophages in the bone marrow. She was initially treated with oral prednisolone (PSL) for 2 months, which had a limited effect. However, after treatment with rituximab, the patient's pancytopenia showed improvement, allowing us to rapidly reduce the PSL dosage. The present case suggests the possibility that increased expression of TGF-ß in infiltrating lymphocytes and macrophages of bone marrow may contribute to the pathogenesis of AIMF. Prednisolone combined with rituximab may thus be an effective option for steroid-refractory cases.

Hmga2 collaborates with JAK2V617F in the development of myeloproliferative neoplasms.

High-mobility group AT-hook 2 (HMGA2) is crucial for the self-renewal of fetal hematopoietic stem cells (HSCs) but is downregulated in adult HSCs via repression by MIRlet-7 and the polycomb-recessive complex 2 (PRC2) including EZH2. The HMGA2 messenger RNA (mRNA) level is often elevated in patients with myelofibrosis that exhibits an advanced myeloproliferative neoplasm (MPN) subtype, and deletion of Ezh2 promotes the progression of severe myelofibrosis in JAK2V617F mice with upregulation of several oncogenes such as Hmga2. However, the direct role of HMGA2 in the pathogenesis of MPNs remains unknown. To clarify the impact of HMGA2 on MPNs carrying the driver mutation, we generated ΔHmga2/JAK2V617F mice overexpressing Hmga2 due to deletion of the 3' untranslated region. Compared with JAK2V617F mice, ΔHmga2/JAK2V617F mice exhibited more severe leukocytosis, anemia and splenomegaly, and shortened survival, whereas severity of myelofibrosis was comparable. ΔHmga2/JAK2V617F cells showed a greater repopulating ability that reproduced the severe MPN compared with JAK2V617F cells in serial bone marrow transplants, indicating that Hmga2 promotes MPN progression at the HSC level. Hmga2 also enhanced apoptosis of JAK2V617F erythroblasts that may worsen anemia. Relative to JAK2V617F hematopoietic stem and progenitor cells (HSPCs), over 30% of genes upregulated in ΔHmga2/JAK2V617F HSPCs overlapped with those derepressed by Ezh2 loss in JAK2V617F/Ezh2Δ/Δ HSPCs, suggesting that Hmga2 may facilitate upregulation of Ezh2 targets. Correspondingly, deletion of Hmga2 ameliorated anemia and splenomegaly in JAK2V617F/Ezh2Δ/wild-type mice, and MIRlet-7 suppression and PRC2 mutations correlated with the elevated HMGA2 mRNA levels in patients with MPNs, especially myelofibrosis. These findings suggest the crucial role of HMGA2 in MPN progression.

Severe immune thrombocytopenia possibly elicited by the anti-influenza viral agent peramivir.

A 44-year-old man whose platelet count had been at the lower limit of the normal range for years visited the urgent care department of our hospital for treatment of a high fever and severe fatigue. The influenza A virus was detected, and the patient therefore received the intravenous antiviral agent, peramivir. One week later, he developed systemic petechial rashes. A peripheral blood examination showed a markedly decreased platelet count (3.0×10(9) cells/L), and the bone marrow findings were compatible with a diagnosis of immune thrombocytopenia (ITP). Furthermore, a drug-induced lymphocyte-stimulating test was positive for peramivir. The thrombocytopenia slowly responded to treatment with oral prednisolone. This case suggests that neuraminidase inhibitors, including peramivir, can elicit or worsen ITP.

Pleural solitary fibrous tumor complicated with autoimmune hemolytic anemia.

We herein report a 74-year-old woman who presented with autoimmune hemolytic anemia (AIHA) associated with pleural solitary fibrous tumor (SFT). Her AIHA was initially treated with 1 mg/kg daily of oral prednisolone (PSL) for 2 months, which had a limited effect. However, after surgical tumor resection, the patient showed remarkable improvement of AIHA with normalizations of serum lactate dehydrogenase and bilirubin levels, and we were able to rapidly reduce the PSL dosage. This is the first description of a case of AIHA caused by SFT.

Pulmonary hypertension and refractory heart failure in a patient with Crow-Fukase (POEMS) syndrome.

We experienced the case of a 67-year-old man with refractory heart failure. He presented with dyspnea and progressive pitting edema of the lower limbs. Diuretics were insufficient to improve his symptoms. Cardiac catheterization demonstrated pulmonary hypertension. Additional examinations confirmed polyneuropathy, organomegaly, endocrinopathy and monoclonal gammopathy. The plasma vascular endothelial growth factor (VEGF) level was 1,340 pg/mL. The patient was diagnosed with Crow-Fukase (POEMS) syndrome. Echocardiography detected left ventricular hypertrophy and diastolic dysfunction. Polysomnography demonstrated severe sleep-disordered breathing. We herein describe a case of pulmonary hypertension with Crow-Fukase syndrome accompanied by left ventricular diastolic dysfunction and sleep-disordered breathing.

Low concentration of serum haptoglobin has impact on understanding complex pathophysiology in patients with acquired bone marrow failure syndromes.

To clarify whether measurement of serum haptoglobin (Hp) has impact on understanding pathophysiology in bone marrow failure (BMF) syndromes, we investigated concentrations of serum Hp by nephelometric procedure in 156 Japanese patients with BMF, including 54 aplastic anemia (AA), 50 paroxysmal nocturnal hemoglobinuria (PNH), and 52 myelodysplastic syndromes (MDS) patients. The frequencies with low concentrations of serum Hp (<42 mg/dL) in PNH patients (98.0%) were significantly higher than those in AA (27.8%; P < 0.0001) and MDS (38.5%; P < 0.0001) patients. In AA patients, white blood cell (WBC), absolute neutrophil, and platelet counts were significantly decreased in the group (n = 15) with low concentrations of serum Hp than in that (n = 39) with normal concentrations of it, and WBC counts were positively correlated with concentrations of serum Hp, suggesting that WBC counts may affect the concentrations. In MDS patients, hemoglobin concentrations and serum iron were significantly decreased and increased, respectively, in the group (n = 20) with low concentrations of serum Hp than in that (n = 32) with normal concentrations of it, and the values of serum iron were inversely correlated with concentrations of serum Hp, suggesting that ineffective erythropoiesis may affect the concentrations. Several AA and MDS patients with low concentrations of serum Hp had Coombs-negative autoimmune hemolytic anemia determined by immunoradiometric assay. In conclusion, several factors in conjunction with pathophysiology contribute to decrease of serum Hp in BMF.

Hematopoietic stem cell transplantation in the Department of Hematology, Fukushima Medical University.

From 1996 to the end of 2009, a total of 114 cases of hematopoietic stem cell transplantation were performed in the Department of Hematology, Fukushima Medical University. We report here a general overview of our results. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) was performed in 37 cases of acute leukemia, 10 of myelodysplastic syndrome, 5 of aplastic anemia, and 5 others. The 5-year survival rate with allo-HSCT was 51.1%. Autologous hematopoietic stem cell transplantation (auto-HSCT) was performed in 34 cases of malignant lymphoma, 15 of multiple myeloma, and 8 others. The 5-year patient survival rate was 75.2% with malignant lymphoma and 46.7% with multiple myeloma. These results are comparable to those from a nationwide survey in Japan, confirming that our hospital has attained a creditable level as a transplantation center.

A long-term remission of renal amyloidosis with nephrotic syndrome after autologous peripheral blood stem-cell transplantation.

Renal amyloidosis is typically characterized by nephrotic syndrome, often with massive proteinuria and refractory peripheral edema. We report the case of a patient with renal amyloidosis associated with nephrotic syndrome who maintained remission for 6 years after undergoing high-dose chemotherapy followed by autologous peripheral blood stem-cell transplantation (auto-PBSCT). The patient was a man aged in his 50s who had developed nephrotic syndrome. Bone marrow aspiration and kidney biopsy determined that the cause of the nephrotic syndrome was renal amyloidosis due to multiple myeloma, and the patient was admitted to our department in July 2003. After one course of chemotherapy, auto-PBSCT was performed in March 2004. Following transplantation, serum M-protein was no longer detectable from March 2005, and the patient achieved complete hematological remission. Subsequently, proteinuria decreased, serum albumin levels normalized, and nephrotic syndrome improved. As of 6 years after transplantation, in March 2010, the patient remained in remission, meaning that auto-PBSCT proved extremely effective as a treatment for renal amyloidosis in this case.

CD4+ T cells in aged or thymectomized recipients of allogeneic stem cell transplantations

BACKGROUND: CD4+CD25highFOXP3+ regulatory T (Treg) cells, which include thymus-derived and peripherally induced cells, play a central role in immune regulation, and are therefore crucial to prevent graft-versus-host disease (GVHD). The increasing use of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for elderly patients with thymus regression, and our case of allo-HSCT shortly after total thymectomy, raised questions about the activity of thymus-derived Treg cells and peripherally induced Treg cells, which are otherwise indistinguishable. RESULTS: We found that despite pre-transplant thymectomy or older age, both naïve and effector Treg cells, as well as naïve and effector conventional T cells, proliferated in allo-HSCT recipients. Higher proportions of total Treg cells 1 month post allo-HSCT, and naïve Treg cells 1 year post allo-HSCT, appeared in patients achieving complete chimera without developing significant chronic GVHD, including our thymectomized patient, compared with patients who developed chronic GVHD. CONCLUSIONS: Treg cells that modulate human allogeneic immunity may arise peripherally as well as in the thymus of allo-HSCT recipients.