[Current state of treatment for myelodysplastic syndromes].

Myelodysplastic syndromes (MDS) are hematopoietic stem cell neoplasms characterized by bone marrow failure with a propensity to develop into acute myeloid leukemia (AML). Recent advances in genome-wide analyses have enabled identification of most somatic gene mutations responsible for MDS, and multiplex gene-panel testing for hematological malignancies will be available soon. Thus, identification of genetic abnormalities is now enabling precise diagnosis and risk-stratification of MDS. Recently, two diagnostic classification systems for MDS have been published as updates to the previous WHO classification of myeloid tumors. The IPSS-M has also been proposed as a new risk-stratification system based on genetic abnormalities and known prognostic factors. Following identification of pathological processes in MDS, therapeutic agents that can alter the course of disease, including azacitidine and lenalidomide, were approved and became available in Japan. Several novel therapeutic agents are under development as well. This paper will discuss updated diagnostic and risk-stratification systems, as well as standard treatment strategies for MDS.

[COVID-19 development during the treatment of paroxysmal nocturnal hemoglobinuria].

Paroxysmal nocturnal hemoglobinuria (PNH) is a disorder in which an activated complement causes intravascular hemolysis of erythrocytes that do not have complement regulators. It is critical to monitor the rapid progression of hemolysis caused by infection and thrombosis. As far as we can tell, this is the first report of 5 COVID-19 patients with PNH in Japan. Three patients were being treated with ravulizumab, one with eculizumab, and one with crovalimab. All five cases had received two or more COVID-19 vaccinations. COVID-19 was classified as mild in four cases and moderate in one. None of the cases required the use of oxygen, and none became severe. All of them experienced breakthrough hemolysis, and two required red blood cell transfusions. In any case, no thrombotic complications were observed.

[Updated treatment strategies for myelodysplastic syndromes].

Myelodysplastic syndromes (MDS) are hematopoietic stem cell neoplasms, which are characterized as bone marrow failure with a propensity to develop acute myeloid leukemia (AML). Patients with MDS tend to be of higher age, with usually poor antineoplastic chemotherapy response. The life prognosis of MDS is poor, and its curative treatment is limited to allogeneic hematopoietic cell transplantation. Recent advances in hematopoietic cell transplantation, including alternative donors or reduced-intensity conditioning regimens, resulted in an expanded treatment indication for patients of higher age. Moreover, several novel therapeutic agents are implemented after the elucidation of pathological processes in MDS. Therapeutic agents that can alter the disease course, including azacitidine and lenalidomide, are approved and available in Japan. Additionally, other therapeutic agents for MDS, such as erythropoiesis-stimulating agents and oral iron chelators, are also available, and clinical trials for novel agents are also underway. This study discussed the updated risk-stratified treatment strategies for MDS and the development of novel agents.

[Management of lower-risk myelodysplastic syndromes].

Myelodysplastic syndromes (MDS) are neoplastic diseases of the hematopoietic stem cells, caused by genetic mutations. The clinical courses of MDS are highly variable based on the underlying genetic aberrations, ranging from slowly progressing cytopenia to rapidly-manifesting fatal diseases, including the development of acute myelogenous leukemia. The management of lower-risk MDS, which is risk-stratified based on the revised International Prognostic Scoring System (IPSS-R), mainly consists of a supportive therapy, including blood transfusion to treat anemia and thrombocytopenia. Recently, three novel drugs were approved, which became available in Japan. These include darbepoetin alfa, an erythropoiesis-stimulating agent; lenalidomide, which is specifically active for anemia of 5q- syndrome; and deferasirox, an oral iron-chelating agent. Decision analyses also provide evidence in determining the optimal timing for the potentially curative allogeneic hematopoietic stem cell transplantation for lower-risk MDS. Thus, the management of lower-risk MDS should be optimized using these novel agents and newly available evidence.

[Effective treatment of POEMS syndrome accompanied by plasmacytoma with lenalidomide, dexamethasone, and local irradiation].

A 70-year-old woman experienced pain in both gastrocnemius muscles, numbness in the toes, and muscle weakness in both the legs that lasted for two months. After getting admitted to our hospital, the muscle weakness extended to both her arms, and nerve conduction studies revealed decreased nerve conduction velocity, which was more prominent in the elbow and the axilla than in the wrist. A magnetic resonance imaging revealed a tumor in the right femoral neck, which was histologically diagnosed as plasmacytoma. Laboratory findings revealed IgA lambda type M protein and an elevated VEGF level of 2,320 pg/ml; edema was present in both the legs. After a diagnosis of POEMS syndrome, lenalidomide and dexamethasone treatment were initiated simultaneously, along with irradiation. The treatment improved polyneuropathy, along with a decrease in the VEGF level. Increased vascular permeability due to elevated VEGF led to the development of neuropathy of POEMS syndrome, and treatment against proliferating monoclonal plasma cells is effective. In the present case, we believe that a prompt control of the plasmacytoma with novel therapeutic agents for myeloma with irradiation resulted in the improvement of the neurological symptoms.

[Acquired hemophilia A requiring plasma exchange and mechanical ventilation].

A 56-year-old man who sustained a right waist injury 1 month ago, reported to our department complaining of pain in the right waist and femur for 1 day. In a computed tomography examination, hematoma of the right iliopsoas muscle was revealed, and arterial embolization was immediately performed but was not effective. Laboratory findings showed hemoglobin levels as 5.4 g/dl, platelet of 20.2×104/µl, prothrombine time of 13.1 s, partial thromboplastin time (APTT) of 81.1 s, and a convex upward curve of the APTT cross-mixing test. The activity of the coagulation factor VIII was <1.0%, but its amount was 120%, and the level of factor VIII inhibitor was 130 Bethesda Unit/ml. Disseminated intravascular coagulation was not noted. Under the diagnosis of acquired hemophilia A, treatment with prednisolone and recombinant activated factor VII was initiated. However, APTT remained prolonged, and intubation and mechanical ventilation were required because of right hemothorax. After steroid pulse therapy and plasma exchange, APTT returned to its normal range, and the inhibitor disappeared. Thus, we finally succeeded in extubation. This case indicated that intensive care may be necessary in the early phase treatment for acquired hemophilia A.

A nationwide survey of hypoplastic myelodysplastic syndrome (a multicenter retrospective study).

Hypoplastic myelodysplastic syndrome (hMDS) is a distinct entity with bone marrow (BM) hypocellularity and the risk of death from BM failure (BMF). To elucidate the characteristics of hMDS, the data of 129 patients diagnosed between April 2003 and March 2012 were collected from 20 institutions and the central review team of the National Research Group on Idiopathic Bone Marrow Failure Syndromes, and compared with 115 non-hMDS patients. More RA and fewer CMMoL and RAEB-t in French-American-British (FAB) and more RCUD and MDS-U and fewer RCMD in World Health Organization (WHO) classifications were found in hMDS than non-hMDS with significant differences. The overall survival (OS) and AML progression-free survival (AML-PFS) of hMDS were higher than those of non-hMDS, especially in patients at age ≥50 and of lower risk in Revised International Prognostic Scoring System (IPSS-R). In competing risks analysis, hMDS exhibited decreased risk of AML-progression in lower IPSS or IPSS-R risk patients, and higher risk of death from BMF in patients at age ≥50. Poor performance status (PS ≥2) and high karyotype risks in IPSS-R (high and very high) were significant risk factors of death and AML-progression in Cox proportional hazards analysis.

Pathophysiology of MDS: genomic aberrations.

Myelodysplastic syndromes (MDS) are characterized by clonal proliferation of hematopoietic stem/progenitor cells and their apoptosis, and show a propensity to progress to acute myelogenous leukemia (AML). Although MDS are recognized as neoplastic diseases caused by genomic aberrations of hematopoietic cells, the details of the genetic abnormalities underlying disease development have not as yet been fully elucidated due to difficulties in analyzing chromosomal abnormalities. Recent advances in comprehensive analyses of disease genomes including whole-genome sequencing technologies have revealed the genomic abnormalities in MDS. Surprisingly, gene mutations were found in approximately 80-90% of cases with MDS, and the novel mutations discovered with these technologies included previously unknown, MDS-specific, mutations such as those of the genes in the RNA-splicing machinery. It is anticipated that these recent studies will shed new light on the pathophysiology of MDS due to genomic aberrations.

ALK-negative anaplastic large cell lymphoma with loss of CD30 expression during treatment with brentuximab vedotin.

A 59-year-old woman with anaplastic large cell lymphoma (ALCL), ALK-negative, was treated with brentuximab vedotin (BV) against relapse after 6 regimens of systemic chemotherapy and radiation. Despite achieving an initial response, skin lesions worsened after 11 courses. A skin biopsy after the development of resistance to BV confirmed loss of CD30 expression by the tumor cells, suggesting a possible cause of resistance. This case shows that down-regulation of CD30 does occur during BV treatment, resulting in resistance to this drug. Because of this possibility, in the future, expression of CD30 should be carefully monitored with extended use of BV against ALCL.

Intracellular reactive oxygen species mark and influence the megakaryocyte-erythrocyte progenitor fate of common myeloid progenitors.

While most studies regarding reactive oxygen species (ROS) focus on their deleterious biological effects, a growing body of evidence indicates the importance of ROS as critical mediators of several signaling pathways, including those involved in hematopoiesis. In this study, we show the critical role of ROS in lineage decision of myeloid progenitors. In megakaryocyte-erythrocyte progenitor cells (MEP), intracellular ROS levels were found to be as low as those in hematopoietic stem cells (HSC). In contrast, remarkably high intracellular ROS levels were observed in granulocyte-monocyte progenitor cells. Intracellular ROS levels in common myeloid progenitors (CMP) were inversely correlated with their MEP differentiation potential. Moreover, gene set enrichment analysis revealed that ROS-low CMP showed gene expression patterns similar to those of MEP, indicating that intracellular ROS levels mark the fate of CMP. In in vitro assays, ROS significantly suppressed the generation of MEP and the formation of megakaryocyte-erythrocyte colonies from CMP. In ROS-high CMP, expression of colony-stimulating factor one receptor (CSF1R) was highly upregulated, and its surface expression correlated with their granulocyte-monocyte differentiation potential. Furthermore, ROS was found to induce the expression of CSF1R mRNA in a leukemia cell line. These data provide novel insights into the relationship between ROS and the hematopoietic differentiation system.

Modified ESHAP regimen for relapsed/refractory T cell lymphoma: a retrospective analysis.

Peripheral T cell lymphomas account for approximately 10 % of all the non-Hodgkin lymphomas and are characterized by an aggressive clinical course and poor treatment outcome. In contrast to the improvement in the treatment of B cell lymphomas, there is no established standard chemotherapy regimen for relapsed/refractory T cell lymphomas. Our institute introduced modified ESHAP (mESHAP) regimen to reduce renal toxicity of standard ESHAP therapy, in which cisplatin was switched to carboplatin. We retrospectively analyzed the efficacy of mESHAP against relapsed/refractory T cell lymphomas. Twenty-two patients with relapsed/refractory T cell lymphomas were treated with mESHAP regimen at the University of Tokyo Hospital between January 2001 and December 2012. The median age was 59 years (range, 36-77). The diagnosis comprised peripheral T cell lymphoma, not otherwise specified (n = 10), angioimmunoblastic T cell lymphoma (AITL; n = 9), mycosis fungoides (n = 1), and anaplastic lymphoma kinase (ALK)-negative anaplastic large cell lymphoma (n = 2). The median follow-up period was 9.5 months (range, 2.5-62.3). Complete remission (CR) was achieved in four patients (18 %) and partial remission (PR) in three patients (14 %). The median overall survival (OS) and progression-free survival (PFS) were 11.0 and 2.5 months, respectively. Leukopenia was the most frequent side effect and renal impairment was rare. According to a multivariate analysis, better OS and PFS were recorded in patients without bone marrow invasion (OS, hazard ratio (HR) 0.13, p = 0.0079; PFS, HR 0.13, p = 0.0044) or those with AITL (OS, HR 0.21, p = 0.021; PFS, HR 0.15, p = 0.0043). Although overall outcomes of mESHAP for relapsed/refractory T cell lymphomas were not excellent, this regimen remains one of the possible candidates for those with AITL histology or without bone marrow invasion.

Serial profile of vitamins and trace elements during the acute phase of allogeneic stem cell transplantation.

Currently, we utilize vitamins and trace elements formulations that are not prepared specifically for patients receiving hematopoietic stem cell transplantation (HSCT), and adequacy of this strategy has not been evaluated. We prospectively measured blood level of vitamins and trace elements in 15 patients once per week at 6 time points around the acute phase of allogeneic HSCT. We provided standard nutrition support, including administration of parenteral nutrition with vitamin and trace elements formulation in case of impairment of oral intake. Most patients had vitamin B1 deficiency from the start of preparative regimens. Vitamin C deficiency was prominent throughout the acute phase of HSCT and this was significantly associated with high inflammatory markers, C-reactive protein and ferritin. Remarkable vitamin K overload associated with administration of parenteral supplementation and ferritin overload caused by repeated transfusions was observed. Moderate deficiency of zinc was at least partially linked to gastrointestinal loss by diarrhea. We revealed several features of vitamin and trace element status in the acute phase of HSCT and provided a basis for attempts to improve the nutritional condition in HSCT recipients.

Favorable outcomes of tacrolimus compared with cyclosporine A for GVHD prophylaxis in HSCT for standard-risk hematological diseases.

Although calcineurin inhibitors (CNIs) with short-term methotrexate (stMTX) constitute standard prophylaxis for graft-versus-host diseases (GVHD) in hematopoietic stem cell transplantations (HSCT), comparative efficacy of cyclosporine A (CsA) and tacrolimus (Tac) still remains unclear. We have altered GVHD prophylaxis for standard-risk hematological malignancies from CsA (target trough level, 500 ng/mL) to Tac (15 ng/mL) both with stMTX in May 2008, enabling us to compare the efficacy of CNIs with little selection biases. The cumulative incidence of acute and chronic GVHD was comparable for CsA and Tac. Among the GVHD low-risk patients who received stem cells from matched sibling donors or cord blood, the Tac arm had a trend for favorable control of grade III-IV acute GVHD (6.7 vs. 30.0 %, p = 0.2), which may contribute to the significantly better overall survival (p = 0.048) and relapse-free survival (p = 0.043) in that group. Inadequate concentration of CNIs in early phase of HSCT affected the cumulative incidence of acute GVHD in the CsA but not in the Tac arm. There were no differences in the GVHD incidence and survival outcomes between CsA and Tac in the GVHD high-risk subgroup. This study underlies the significance of maintaining adequate CsA concentration in standard-risk HSCT.

Development of hairy cell leukemia in familial platelet disorder with predisposition to acute myeloid leukemia.

Abstract Familial platelet disorder with predisposition to acute myeloid leukemia (FPD/AML) is an autosomal dominant disorder characterized by mild to moderate thrombocytopenia with or without its impaired function, inherited RUNX1 mutation and high incidence of myeloid malignancy, such as myelodysplastic syndrome or acute myeloid leukemia. A 72-year-old male visited our institute because of gradually progressive pancytopenia and splenomegaly, and was diagnosed as having hairy cell leukemia. He was administered one course of intravenous cladribine (0.12 mg/kg, day 1-5) and achieved hematological complete response. Mutation analyses of RUNX1 gene were underwent because familial history of hematological malignancies evoked a possibility of FPD/AML. As a result, RUNX1 L445P mutation was identified in the peripheral blood and the mutation was considered as germ-line mutation because the same mutation was detected in the buccal mucosa. BRAF V600E mutation was also identified in the peripheral blood but not in the buccal mucosa. To our knowledge, this is the first report of B cell malignancy arising from FPD/AML.

Risk factors for drug-resistant pathogens in community-acquired and healthcare-associated pneumonia.

RATIONALE: Identification of patients with drug-resistant pathogens at initial diagnosis is essential for treatment of pneumonia. OBJECTIVES: To elucidate clinical features of community-acquired pneumonia (CAP) and healthcare-associated pneumonia (HCAP), and to clarify risk factors for drug-resistant pathogens in patients with CAP and HCAP. METHODS: A prospective observational study was conducted in hospitalized patients with pneumonia at 10 institutions in Japan. Pathogens identified as not susceptible to ceftriaxone, ampicillin-sulbactam, macrolides, and respiratory fluoroquinolones were defined as CAP drug-resistant pathogens (CAP-DRPs). MEASUREMENTS AND MAIN RESULTS: In total, 1,413 patients (887 CAP and 526 HCAP) were analyzed. CAP-DRPs were more frequently found in patients with HCAP (26.6%) than in patients with CAP (8.6%). Independent risk factors for CAP-DRPs were almost identical in patients with CAP and HCAP. These included prior hospitalization (adjusted odds ratio [AOR], 2.06; 95% confidence interval [CI], 1.23-3.43), immunosuppression (AOR, 2.31; 95% CI, 1.05-5.11), previous antibiotic use (AOR, 2.45; 95% CI, 1.51-3.98), use of gastric acid-suppressive agents (AOR, 2.22; 95% CI, 1.39-3.57), tube feeding (AOR, 2.43; 95% CI, 1.18-5.00), and nonambulatory status (AOR, 2.45; 95% CI, 1.40-4.30) in the combined patients with CAP and HCAP. The area under the receiver operating characteristic curve for counting the number of risk factors was 0.79 (95% CI, 0.74-0.84). CONCLUSIONS: The clinical profile of HCAP was different from that of CAP. However, physicians can predict drug resistance in patients with either CAP or HCAP by taking account of the cumulative number of the risk factors. Clinical trial registered with https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr.cgi?function=brows&action=brows&type=summary&recptno=R000004001&language=E ; number UMIN000003306.

Dynamic metabolic changes during the first 3 months after 90Y-ibritumomab tiuxetan radioimmunotherapy.

OBJECTIVE: To elucidate the time course of tumor metabolism during the first 3 months after (90)Y-ibritumomab tiuxetan radioimmunotherapy (RIT) in patients with refractory malignant lymphoma. MATERIALS AND METHODS: Seven patients with recurrent follicular lymphoma underwent FDG-PET imaging before and after 1-, 4-, and 12-week RIT with (90)Y-ibritumomab tiuxetan. Tumor metabolic activity on FDG-PET scans was assessed as the maximum standard uptake value (SUVmax). RESULTS: Decrease in metabolism was detected 1 week after RIT. In the most decreased lesion, SUVmax decreased to 20% of the baseline value during the first week. Most lesions continued to decrease for up to 4 weeks. Some lesions showed increased metabolism from 4 to 12 weeks, while the level of FDG accumulations at 12 weeks was still lower than the baseline. CONCLUSIONS: Tumor response to RIT could be observed as early as 1 week after the administration of RIT. After tumor activity decreases, the metabolism may increase at least between 4 and 12 weeks. It suggests that the metabolic changes should be carefully evaluated during this period.

Multiple phosphorylation sites are important for RUNX1 activity in early hematopoiesis and T-cell differentiation.

RUNX1 is essential for definitive hematopoiesis and T-cell differentiation. It has been shown that RUNX1 is phosphorylated at specific serine and threonine residues by several kinase families. However, it remains unclear whether RUNX1 phosphorylation is absolutely required for its biological functions. Here, we evaluated hematopoietic activities of RUNX1 mutants with serine (S)/threonine (T) to alanine (A), aspartic acid (D), or glutamic acid (E) mutations at phosphorylation sites using primary culture systems. Consistent with the results of knockin mice, RUNX1-2A, carrying two phospho-deficient mutations at S276 and S293, retained hematopoietic activity. RUNX1-4A, carrying four mutations at S276, S293, T300, and S303, showed impaired T-cell differentiation activity, but retained the ability to rescue the defective early hematopoiesis of Runx1-deficient cells. Notably, RUNX1-5A, carrying five mutations at S276, S293, T300, S303, and S462, completely lost its hematopoietic activity. In contrast, the phospho-mimic proteins RUNX1-4D/E and RUNX1-5D/E exhibited normal function. Our study identifies multiple phosphorylation sites that are indispensable for RUNX1 activity in hematopoiesis.

Evi-1 is a transcriptional target of mixed-lineage leukemia oncoproteins in hematopoietic stem cells.

Ecotropic viral integration site-1 (Evi-1) is a nuclear transcription factor that plays an essential role in the regulation of hematopoietic stem cells. Aberrant expression of Evi-1 has been reported in up to 10% of patients with acute myeloid leukemia and is a diagnostic marker that predicts a poor outcome. Although chromosomal rearrangement involving the Evi-1 gene is one of the major causes of Evi-1 activation, overexpression of Evi-1 is detected in a subgroup of acute myeloid leukemia patients without any chromosomal abnormalities, which indicates the presence of other mechanisms for Evi-1 activation. In this study, we found that Evi-1 is frequently up-regulated in bone marrow cells transformed by the mixed-lineage leukemia (MLL) chimeric genes MLL-ENL or MLL-AF9. Analysis of the Evi-1 gene promoter region revealed that MLL-ENL activates transcription of Evi-1. MLL-ENL-mediated up-regulation of Evi-1 occurs exclusively in the undifferentiated hematopoietic population, in which Evi-1 particularly contributes to the propagation of MLL-ENL-immortalized cells. Furthermore, gene-expression analysis of human acute myeloid leukemia cases demonstrated the stem cell-like gene-expression signature of MLL-rearranged leukemia with high levels of Evi-1. Our findings indicate that Evi-1 is one of the targets of MLL oncoproteins and is selectively activated in hematopoietic stem cell-derived MLL leukemic cells.

Loss of AML1/Runx1 accelerates the development of MLL-ENL leukemia through down-regulation of p19ARF.

Dysfunction of AML1/Runx1, a transcription factor, plays a crucial role in the development of many types of leukemia. Additional events are often required for AML1 dysfunction to induce full-blown leukemia; however, a mechanistic basis of their cooperation is still elusive. Here, we investigated the effect of AML1 deficiency on the development of MLL-ENL leukemia in mice. Aml1 excised bone marrow cells lead to MLL-ENL leukemia with shorter duration than Aml1 intact cells in vivo. Although the number of MLL-ENL leukemia-initiating cells is not affected by loss of AML1, the proliferation of leukemic cells is enhanced in Aml1-excised MLL-ENL leukemic mice. We found that the enhanced proliferation is the result of repression of p19(ARF) that is directly regulated by AML1 in MLL-ENL leukemic cells. We also found that down-regulation of p19(ARF) induces the accelerated onset of MLL-ENL leukemia, suggesting that p19(ARF) is a major target of AML1 in MLL-ENL leukemia. These results provide a new insight into a role for AML1 in the progression of leukemia.