Rapamycin Prolongs Cardiac Allograft Survival in a Mouse Model by Inducing Myeloid-Derived Suppressor Cells.

Mammalian target of rapamycin (mTOR) inhibitors are the main immunosuppressive drugs for organ transplant recipients. Nevertheless, the mechanisms by which mTOR inhibitors induce immunosuppression is not fully understood. Myeloid-derived suppressor cells (MDSCs) maintain host immunity; however, the relationship between mTOR inhibitors and MDSCs is unclear. Here, the results from a murine cardiac transplantation model revealed that rapamycin treatment (3 mg/kg, intraperitoneally on postoperative days 0, 2, 4, and 6) led to the recruitment of MDSCs and increased their expression of inducible nitric oxide synthase (iNOS). Immunohistochemical analysis revealed that rapamycin induced the migration of iNOS-expressing MDSCs into the subintimal space within the allograft vessels, resulting in a significant prolongation of graft survival compared with that in the untreated group (67 days vs. 7 days, respectively). These effects were counterbalanced by the administration of an anti-Gr-1, which reduced allograft survival to 21 days. Moreover, adoptive transcoronary arterial transfer of MDSCs from rapamycin-treated recipients prolonged allograft survival; this increase was reversed by the anti-Gr-1 antibody. Finally, co-administration of rapamycin and a mitogen-activated protein kinase kinase (MEK) inhibitor trametinib reversed rapamycin-mediated MDSC recruitment. Thus, the mTOR and Raf/MEK/extracellular signal regulated kinase (ERK) signaling pathways appear to play an important role in MDSC expansion.

Risk-adjusted assessment of incidence and quantity of blood use in acute-care hospitals in Japan: an analysis using administrative data.

BACKGROUND AND OBJECTIVES: Continuous monitoring of blood use and feedback on transfusions are effective in decreasing inappropriate blood transfusions. However, traditional methods of monitoring have practical challenges, such as the limited availability of experts and funding. Administrative data including a patient classification system may be employed for risk-adjusted assessment of hospital-wide blood use. MATERIALS AND METHODS: We conducted an audit of blood use at two hospitals and determined proportions of appropriate blood use at each hospital. We then used administrative data of 587,045 cases provided by 73 hospitals to develop two mathematical models to calculate risk-adjusted use of blood products. The first model is a logistic regression model to predict the percentage of transfused patients. Patient demographics, surgery and diagnostic groups were utilized as predictors of transfusion. The second model is a case-mix adjusted model which predicts hospital-wide use of units of blood products from the distribution of diagnosis-related groups. For each model, the observed to expected (O/E) ratio of blood use in each hospital was calculated. We compared resultant ratios with proportions of appropriate blood use in two of the hospitals studied. RESULTS: Both models showed good prediction abilities. O/E ratios calculated using the two models were relevant to proportions of appropriate transfusions. CONCLUSIONS: Risk-adjusted assessments of blood product use based on administrative data allow hospital-wide evaluation of transfusion use. Comparing blood use between different hospitals contributes toward establishing appropriate transfusion practices.

The Bcr-Abl kinase inhibitor INNO-406 induces autophagy and different modes of cell death execution in Bcr-Abl-positive leukemias.

Bcr-Abl tyrosine kinase (TK) inhibitors are promising therapeutic agents for Bcr-Abl-positive (Bcr-Abl(+)) leukemias. Although they are known to promote caspase-mediated apoptosis, it remains unclear whether caspase-independent cell death-inducing mechanisms are also triggered. Here we demonstrated that INNO-406, a second-generation Bcr-Abl TK inhibitor, induces programmed cell death (PCD) in chronic myelogenous leukemia (CML) cell lines through both caspase-mediated and caspase-independent pathways. The latter pathways include caspase-independent apoptosis (CIA) and necrosis-like cell death (CIND), and the cell lines varied regarding which mechanism was elicited upon INNO-406 treatment. We also observed that the propensity toward CIA or CIND in cells was strongly associated with cellular dependency on apoptosome-mediated caspase activity. Cells that undergo CIND have a high apoptosome activity potential whereas cells that undergo CIA tend to have a lower potential. Moreover, we found that INNO-406 promotes autophagy. When autophagy was inhibited with chloroquine or gene knockdown of beclin1 by shRNA, INNO-406-induced cell death was enhanced, which indicates that the autophagic response of the tumor cells is protective. These findings suggest new insights into the biology and therapy of Bcr-Abl(+) leukemias.

Apoptosis-based dual molecular targeting by INNO-406, a second-generation Bcr-Abl inhibitor, and ABT-737, an inhibitor of antiapoptotic Bcl-2 proteins, against Bcr-Abl-positive leukemia.

Bcr-Abl is the cause of Philadelphia-positive (Ph(+)) leukemias and also constitutes their principal therapeutic target, as exemplified by dramatic effects of imatinib mesylate. However, mono-targeting of Bcr-Abl does not always achieve complete leukemia eradication, and additional strategies those enable complete elimination of leukemic cells are desired to develop. Here we demonstrate that INNO-406, a much more active Bcr-Abl tyrosine kinase inhibitor than imatinib, augments the activities of several proapoptotic Bcl-2 homology (BH)3-only proteins (Bim, Bad, Bmf and Bik) and induces apoptosis in Ph(+) leukemia cells via Bcl-2 family-regulated intrinsic apoptosis pathway. ABT-737, an inhibitor of antiapoptotic Bcl-2 and Bcl-X(L), greatly enhanced the apoptosis by INNO-406, even in INNO-406-less sensitive cells with Bcr-Abl point mutations except T315I mutation. In contrast, co-treatment with INNO-406 and other pharmacologic inducers of those BH3-only proteins, such as 17-allylaminogeldanamycin, an heat shock protein-90 inhibitor, or PS-341, a proteasome inhibitor, did not further increase the BH3-only protein levels or sensitize leukemic cells to INNO-406-induced apoptosis, suggesting a limit to how much expression levels of BH3-only proteins can be increased by anticancer agents. Thus, double-barrelled molecular targeting for Bcr-Abl-driven oncogenic signaling and the cell protection by antiapoptotic Bcl-2 family proteins may be the rational therapeutic approach for eradicating Ph(+) leukemic cells.

Dexamethasone Prolongs Cardiac Allograft Survival in a Murine Model Through Myeloid-derived Suppressor Cells.

BACKGROUND: Recently, myeloid-derived suppressor cells (MDSCs) have attracted considerable attention because of their cancer-promoting and immunosuppressive effects. The glucocorticoid dexamethasone (Dex) is an important immunosuppressive agent used to treat autoimmune diseases and organ transplant rejection. However, the mechanism by which it modulates the immune system is not completely understood. MATERIAL AND METHODS: In this study, we investigated the mechanisms by which Dex modulated the immune response in mice given an allogeneic cardiac transplant. RESULTS: Dex injection significantly prolonged heart graft survival compared with phosphate-buffered saline-injected controls. Dex treatment increased the number of splenic MDSCs. Moreover, Gr-1high/CD11b+ MDSCs and CD3+/CD4+/Foxp3+ regulatory T cells (Tregs) were significantly increased in the Dex group compared with controls. Administration of anti-Gr-1 antibody (Ab) to the Dex group significantly shortened mouse heart graft survival. In addition, anti-Gr-1 Ab treatment significantly reduced Tregs in the Dex + anti-Gr-1 co-treatment group compared with the Dex group. These observations suggest that Dex treatment increased both MDSCs and Tregs, and that MDSCs regulated the incidence of Tregs in this immunosuppressive pathway. CONCLUSION: An important role of Dex in the prevention of the rejection of cardiac grafts in mice is to expand MDSCs and Tregs.

Myeloid-derived Suppressor Cells Recruit CD4(+)/Foxp3(+) Regulatory T Cells in a Murine Cardiac Allograft.

INTRODUCTION: Myeloid-derived suppressor cells (MDSCs) play an important role in regulating allograft rejection in organ transplantation. On the other hand, CD3(+)/CD4(+)/FOXP3(+) regulatory T cells (Tregs) also are of vital importance in immunological tolerance. We previously revealed that adoptive transfer of MDSCs recruited Tregs in the spleen. However, it is still uncertain whether MDSCs are capable of recruiting Tregs to an allograft in vivo. OBJECTIVES: We conducted adoptive transfer experiments of MDSCs to clarify the effects of MDSCs on Tregs in vivo. METHODS: Gr-1(+)/CD11b(+) MDSCs were isolated from rapamycin-treated cardiac transplant (CTx) recipients (3 mg/kg, intraperitoneally on postoperative days [POD] 0, 2, 4, and 6) on POD 7 by magnetic-activated cell sorting (purity >95%). In murine heterotopic cardiac transplantation, 2 × 10(6) MDSCs were transferred into the graft aorta 5 minutes before reperfusion. RESULTS: Flow cytometric analyses of a cardiac allograft on POD 7 showed that MDSCs derived from rapamycin-treated CTx mice (MDSCs-Rap) transfer led to significant recruitment of Tregs compared with a PBS-injected allograft. The level of programmed death ligand-1 (PD-L1) on MDSCs-Rap was higher than those from non-treated recipients. Furthermore, pathological findings also confirmed accumulation of Foxp3(+) Tregs in an allograft. CONCLUSION: Induced PD-L1 on MDSCs might result in recruitment of Tregs. These results suggested that functional MDSCs possessed an ability to induce Tregs in a cardiac allograft and developed a tendency to immunological tolerance.

Mobilization of hematopoietic primitive and committed progenitor cells into blood in mice by anti-vascular adhesion molecule-1 antibody alone or in combination with granulocyte colony-stimulating factor.

OBJECTIVE: One of the mechanisms for mobilization of hematopoietic stem cells and progenitor cells is alternation of adhesion molecules. We investigated the mobilization of hematopoietic progenitor cells in blood by administration of anti-vascular cell adhesion molecule (VCAM)-1 antibody (Ab) in mice. MATERIALS AND METHODS: Twelve- to 14-week old C57BL/6J mice were injected intravenously with anti-VCAM-1 Ab and anti-very late antigen (VLA)-4 Ab at a dose of 5 mg/kg for 2 days. RESULTS: The number of colony-forming cells (CFCs) in blood was increased 11.4-fold after anti-VCAM-1 Ab treatment, but the number of CFCs was not increased after treatment with anti-VLA-4 Ab. The number of colony-forming unit spleen (CFU-S) also was increased 21.6-fold in the peripheral blood by administration of anti-VCAM-1 Ab. The number of CFCs and CFU-S in the bone marrow of mice treated with anti-VCAM-1 Ab was decreased and that in the spleen also was decreased. On administration of recombinant human granulocyte colony-stimulating factor (125 microg/kg twice daily) with anti-VCAM-1 Ab, the numbers of CFCs and CFU-S were increased 141.8-fold and 439-fold, respectively. CONCLUSIONS: These observations demonstrated that administration of anti-VCAM-1 Ab induced mobilization of hematopoietic progenitor cells into blood from bone marrow and spleen and that granulocyte colony-stimulating factor has synergistic effects on anti-VCAM-1 Ab-induced mobilization.

Serum levels of endogenous and exogenous granulocyte colony-stimulating factor after autologous blood stem cell transplantation.

Although the administration of recombinant human granulocyte colony-stimulating factor (rhG-CSF) enhances myeloid engraftment and reduces infectious morbidity after autologous and allogeneic bone marrow transplantations, the effect of rhG-CSF on neutrophil recovery in autologous blood stem cell transplantation (ABSCT) is controversial. We previously demonstrated that a low dose, delivered subcutaneously, of rhG-CSF (50 micrograms/m2) accelerates neutrophil recovery in ABSCT, but the optimal dosage of rhG-CSF is not known. To elucidate the effect of rhG-CSF on neutrophil recovery, we determined serum levels of endogenous and exogenously administered G-CSF in 24 patients receiving ABSCT. Of these, five received bolus subcutaneous injection of 50 micrograms/m2 rhG-CSF, 10 received 150 micrograms/m2, and nine received no rhG-CSF. Endogenous G-CSF levels rose immediately after ABSCT, and an inverse correlation was found between the serum level of G-CSF and the absolute neutrophil count (r = -0.73, p < 0.01). The pre-dose level in patients receiving rhG-CSF rose gradually, reaching a maximum between days 3 and 6. The level gradually decreased as the neutrophil count began to rise, even through administration of the same dose of rhG-CSF continued. Pharmacokinetic data showed that the half-life of elimination of G-CSF (t1/2) exceeded 15 hours during severe neutropenia but decreased during the recovery of neutrophils. These observations suggest that neutrophils provide a negative feedback mechanism for clearing G-CSF from the circulation. Pre-dose levels of G-CSF in patients receiving 50 micrograms/m2 rhG-CSF reached 10 ng/mL, equivalent to the concentrations used in clonogenic assay in vitro to stimulate myeloid progenitor cells.

A newly developed bisphosphonate, YM529, is a potent apoptosis inducer of human myeloma cells.

We examined the effect of YM529, a newly developed third-generation bisphosphonate (BP), on the growth of human myeloma cell lines using the trypan blue dye exclusion test and Alamar blue assay. BPs induced inhibition of proliferation in all cell lines dose-dependently, and YM529 had a most potent growth inhibitory effect, followed by incadronate and pamidronate. Flow cytometric analysis using annexinV and 7AAD showed that YM529 most significantly induced apoptosis of all myeloma cell lines. These observations suggested that YM529 is a potent apoptosis inducer of myeloma cells, and might have some benefit not only on the improvement of bone lesions but also on survival in some myeloma patients.

Clinicopathological features of myeloid/natural killer (NK) cell precursor acute leukemia.

Four patients (three males and one female) were diagnosed as myeloid/natural killer (NK) cell precursor acute leukemia in our department. Two patients showed the extramedullary involvement at initial presentation. Leukemic cells expressed CD7, CD33, CD45 and CD56 in all patients. Additionally, CD13, CD34, HLA-DR, cytoplasmic CD3 and myeloperoxidase were expressed in some patients. Trisomy 10 was found in two patients, which has not been reported in this disease. Therefore, myeloid/NK cell precursor acute leukemia might be rather heterogeneous especially in chromosomal abnormality though it seemed to constitute the distinct clinical entity among acute myeloid leukemia of M0 subtype.

Collection of peripheral blood stem cells mobilized by high-dose Ara-C plus VP-16 or aclarubicin followed by recombinant human granulocyte-colony stimulating factor.

We developed an effective method for harvesting large numbers of peripheral blood stem cells (PBSC) for use in autotransplantation. Twenty patients with hematological malignancies were treated with high doses of Ara-C (12 g/m2) and VP-16/aclarubicin followed by administration of rhG-CSF (50 micrograms/m2). The optimal time for starting PBSC collection was determined by monitoring the CD34-positive stem cells in blood using immunomagnetic beads. PBSC were collected with a CS-3000 blood cell separator. A total blood volume between 7000 and 9000 ml was processed in each apheresis. Under these conditions, a total of 64 apheresis procedures was performed in the 20 patients. The mean numbers of mononuclear cells and of CFU-GM harvested per apheresis were 4.1 x 10(8)/kg and 110 x 10(4)/kg, respectively. A number of CFU-GM sufficient for engraftment (> 30 x 10(4)/kg) could be harvested by a single apheresis in 15 of the 20 patients. So far, 11 patients have been transplanted with PBSC and obtained rapid hematopoietic recovery. The median time to recover neutrophils more than 0.5 x 10(9)/l was 10 days, and that for platelets 50 x 10(9)/l was 11 days. This method for harvesting large numbers of PBSC allows safer autotransplantation in patients with chemoradiosensitive tumors, and is applicable to older patients.

Successful non-T cell-depleted HLA haplo-identical three-loci mismatched hematopoietic stem cell transplantation from mother to son based on the feto-maternal microchimerism in chronic myelogenous leukemia.

A 17-year-old male with chronic myelogenous leukemia in blast crisis received a non-T cell-depleted (TCD) HLA haplo-identical three-loci mismatched hematopoietic stem cell transplant (HSCT) from his mother. Long-term feto-maternal microchimerism was detected by nested polymerase chain reaction with sequence-specific primer typing. The post-transplantation prophylaxis against graft-versus-host disease (GVHD) was tacrolimus with minidose methotrexate. Sustained engraftment was obtained. Acute GVHD (grade 2) developed, but improved rapidly. Bone marrow aspiration on day 120 showed complete remission. Non-TCD HLA haplo-identical HSCT based on feto-maternal microchimerism might be feasible and has important implications in the selection of alternative family donors in HSCT.

Subcutaneous infection with Mycobacterium fortuitum after allogeneic bone marrow transplantation.

Reports of cases of mycobacterial infections after SCT are rare. We report a 30-year-old female with a cutaneous infection of Mycobacterium fortuitum 30 months after allogeneic bone marrow transplantation for acute lymphoblastic leukemia. The patient was successfully treated with surgical debridement followed by oral minocycline and clarithromycin. Mycobacterial infections should be considered in SCT patients with undiagnosed refractory chronic cutaneous infection, and surgical debridement is useful for the diagnosis and treatment of such infections.

Effect of granulocyte colony-stimulating factor on hematopoietic recovery after peripheral blood progenitor cell transplantation.

To examine the effect of granulocyte colony-stimulating factor (G-CSF) on hematopoietic recovery after high-dose chemotherapy and peripheral blood progenitor cell transplantation (PBPCT), 20 patients with hematologic malignancies were divided into two groups. One group was given G-CSF at a daily dose of 50 micrograms/m2 subcutaneously, the other received no G-CSF. Neutrophil recovery was accelerated in the G-CSF treated patients and exceeded 0.5 x 10(9)/l at a median of 10 days post-PBPCT compared with 14 days in the control group (p < 0.01). This reduction led to a decrease in antibiotic use and a trend toward fewer febrile days in the G-CSF treated group.

Reconstitution of lymphocyte subsets after peripheral blood stem cell transplantation: two-color flow cytometric analysis.

The reconstitution of lymphocyte subsets after high-dose chemotherapy followed by peripheral blood stem cell transplantation (PBSCT) was studied using two-color flow cytometry in 14 patients with acute leukemia (four AML and two ALL) and malignant lymphoma (six NHL and two HD). The CD3+HLA-DR+ lymphocytes (activated T cells) and CD8+ lymphocytes increased markedly by 4 weeks after PBSCT. Most of the increased CD8+ lymphocytes were CD11b-, S6F1+ cells and CD8+CD11b+ cells remained low throughout the follow-up period. The CD4+ lymphocytes remained below the normal range up to 34 weeks after PBSCT. The ratio of CD4+ to CD8+ lymphocytes (CD4/CD8 ratio) transiently increased and then decreased below 1.0 at 2 weeks after PBSCT. The CD19+ lymphocytes and the CD3-CD16+CD56+ lymphocytes returned to normal levels in the early period. The CD4+CD45RA+ lymphocytes (suppressor-inducer) decreased to below the normal range, while the CD4+CD45RO+ lymphocytes (helper-inducer) increased more rapidly than the CD4+CD45RA+ lymphocytes. This study shows that an immunosuppressed state exists after PBSCT as is seen after bone marrow transplantation (BMT) and that B cell reconstitution is more rapid in PBSCT than in BMT.

Phenotypic differences of CD34-positive stem cells harvested from peripheral blood and bone marrow obtained before and after peripheral blood stem cell collection.

Using two-color flow cytometry, we analyzed the subpopulations of CD34+ stem and progenitor cells in the blood and bone marrow from 10 patients with hematological malignancies. Peripheral blood mononuclear cells (PBMNC) harvested after chemotherapy (high-dose Ara C and VP-16) and rhG-CSF, and BM mononuclear cells, which were obtained before chemotherapy (BMMNCbefore) and after the stem cell collection (BMMNCafter) were isolated by Ficoll-Hypaque centrifugation. The purified cells were stained with FITC-conjugated anti-CD34 antibody and one of the following PE-conjugated antibodies: anti-CD7, CD10, CD11b, CD11c, CD13, CD19, CD33, CD38, CD45RO, CD56, and HLA-DR. CD34+ PBMNC harvested and the CD34+ BMMNCafter expressed CD13 and CD33 more frequently than CD34+ BMMNCbefore but expressed CD10 and CD19 less frequently than CD34+ BMMNCbefore. These data suggested that harvested PBMNC contain more myeloid lineage committed progenitors than BMMNCbefore, which might contribute to the rapid recovery of neutrophils after peripheral blood stem cell transplantation. No significant phenotypic differences of CD34+ cells between harvested PBMNC and BMMNCafter were observed except for the expression of CD11c. CD34+ PBMNC harvested coexpressed CD11c more frequently than both CD34+ BMMNCbefore and CD34+ BMMNCafter, which expression might be associated with commitment to the monocyte lineage.

CD34+/CD41a+ cells best predict platelet recovery after autologous peripheral blood stem cell transplantation.

Reliable markers for megakaryocytic reconstitution after peripheral blood stem cell transplantation (PBSCT) have not been established. To determine a convenient and reliable predictor, we measured the number of megakaryocyte progenitor cells in PBSC grafts by clonogenic and flow cytometric assays. Seventeen patients with hematological and solid malignancies were included in this study. For the clonogenic assay, we used thrombopoietin (TPO) as a growth factor to evaluate the maximum number of megakaryocyte progenitor cells. Using a flow cytometric assay, we examined the expression of platelet glycoproteins on CD34+ cells to count the number of megakaryocyte progenitor cells. We used buffer containing EDTA to prevent platelet adhesion to CD34+ cells and selected CD34+ cells by immunomagnetic beads. The best correlation was observed between the number of CD34+/CD41a+ cells and the time to platelet recovery (P = 0.0205), rather than the total number of CD34+ cells. In addition, a close correlation was observed between the number of CD34+/CD41a+ cells and colony-forming unit megakaryocyte (CFU-MK) (P = 0.0018). These observations suggest that the number of CD34+/CD41a+ cells is the best predictor for platelet reconstitution after PBSCT.

Mobilization of peripheral blood progenitor cells by high-dose Ara C, VP-16 and recombinant human granulocyte colony-stimulating factor: factors affecting progenitor cell yields.

Forty seven patients with hematological malignancies were treated with high doses of cytosine arabinoside (Ara C; 12 g/m2) and etoposide (VP-16), followed by recombinant human granulocyte colony-stimulating factor (rhG-CSF; 50 micrograms/m2). Peripheral blood progenitor cells (PBPC) were collected during rapid leukocyte recovery using a CS-3000 blood cell separator. A blood volume of 9 liters was processed in each apheresis, with 162 apheresis procedures performed. The mean numbers of mononuclear cells (MNC) and colony-forming unit granulocyte-macrophage (CFU-GM) harvested per apheresis were 4.4 x 10(8)/kg and 142.5 x 10(4)/kg, respectively. A sufficient number of CFU-GM for engraftment (> 30 x 10(4)/kg) could be harvested by a single apheresis in 35 of 47 patients (74%). Various factors that influence the collection of progenitor cells were analyzed by univariate and multivariate analyses. The number and duration of previous chemotherapy cycles were the most significant factors affecting CFU-GM yield. In patients with malignant lymphoma, age also had an influence in addition to these two factors. MNC harvested had an impact on CFU-GM yields by univariate analysis. These observations suggest that high-dose Ara C plus VP-16 followed by G-CSF is an effective regimen for harvesting PBPC. PBPC should be collected in the early stage of first-line chemotherapy.

Autoimmune thrombocytopenia following peripheral blood stem cell autografting.

A 22-year-old woman diagnosed as AML (M3) received myeloablative chemotherapy followed by autologous peripheral stem cell transplantation (PBSCT). Rapid hematopoietic reconstitution occurred. By day 10, the neutrophil count was > 0.5 x 10(9)/l and the platelet count > 50 x 10(9)/l. The platelet count was 145 x 10(9)/l on day 20. Purpura developed on the anterior chest and legs on day 50, at which time the platelet count fell to 17 x 10(9)/l. The BM was hypocellular with an increase in megakaryocytes. Platelet-associated IgG (PAIgG) was 88.1 ng/10(7) platelets (normal range 9-25 ng/10(7)); a diagnosis of idiopathic thrombocytopenic purpura (ITP) was made. Prednisolone administration led to an increase in the platelet count and a decrease in PAIgG. Analysis of lymphocyte subsets revealed an increased number of CD3+ gamma/delta T cells. It is postulated that the thrombocytopenia in this case was due to an autoimmune mechanism such as ITP.

Successful peripheral blood stem cell transplantation for myelodysplastic syndrome.

Wilms' tumor (WT1) gene expression is increased in patients with leukemia as well as myelodysplastic syndrome (MDS) and is useful for detection of minimal residual disease (MRD). A 47-year-old man given a diagnosis of refractory anemia with excess of blasts in transformation (RAEB-T) received myeloablative therapy followed by autologous peripheral blood stem cell transplantation (PBSCT). MRD by WT1 expression was not detected in the graft. The patient has been in CR for 25 months after PBSCT. These observations suggest that PBSCT is feasible for patients with RAEB-T and analysis of WT1 expression can be applied for patients with high risk MDS.