Post-cytokine-release Salt Wasting as Inverse Tumor Lysis Syndrome in a Non-cerebral Natural Killer-cell Neoplasm.

The pathogenesis of cerebral/renal salt-wasting syndrome remains unknown. We herein present a case of salt-wasting syndrome with a natural killer-cell neoplasm without cerebral invasion. A 78-year-old man with hemophagocytic syndrome received two cycles of chemotherapy that did not induce tumor lysis syndrome, but repeatedly caused polyuria and natriuresis. The expression of tumor necrosis factor-α in the neoplasm led us to hypothesize that an oncolysis-induced cytokine storm may have caused renal tubular damage and salt wasting. Our theory may explain the pathogenic mechanism of cerebral/renal salt-wasting syndrome associated with other entities, including cerebral disorders, owing to the elevation of cytokine levels after subarachnoid hemorrhage.

Age and Bone Marrow Cellularity are Associated with Response to Eltrombopag in Japanese Adult Immune Thrombocytopenia Patients: A Retrospective Single-Center Study.

In the present retrospective single-center study, we examined the efficacy and safety of eltrombopag, a thrombopoietin (TPO) -receptor agonist (TPO-RA), and found clinical factors associated with its efficacy in Japanese patients with chronic immune thrombocytopenia (ITP). According to the definition of a response, which is to attain a platelet count of more than 50,000/µL at least once during eltrombopag treatment, 42 enrolled patients were divided into two groups: responders (29 patients, 69%) and non-responders (13 patients, 31%). In analyses of the clinical and laboratory data of these two groups, we extracted two factors that are significantly associated with a better response to eltrombopag, which have not been recognized previously, namely, (1) an older age of patients at eltrombopag initiation (≥ 70 years old) and (2) normal or decreased cellularity of iliac bone marrow (BM) biopsy at diagnosis. The significance of patient age contradicts previous findings from studies in which the Caucasian population was the major focus. However, factors such as changes of pharmacokinetics might modulate the effects of eltrombopag in older patients in Japan because East Asians show higher bioavailability of eltrombopag by as-yet-unknown mechanisms. BM cellularity in ITP may represent an impairment and/or lower responsiveness of pluripotent hematopoietic stem cells, not limited to the megakaryocyte (MgK) -platelet axis, to endogenous TPO, because recent evidence shows that TPO-RA can successfully restore hematopoiesis in aplastic anemia. These results should be useful for the therapeutic use of TPO-RA for ITP and also related thrombocytopenia in Japan.

BCOR and BCORL1 mutations in myelodysplastic syndromes and related disorders.

Patients with low-risk myelodysplastic syndromes (MDS) that rapidly progress to acute myeloid leukemia (AML) remain a challenge in disease management. Using whole-exome sequencing of an MDS patient, we identified a somatic mutation in the BCOR gene also mutated in AML. Sequencing of BCOR and related BCORL1 genes in a cohort of 354 MDS patients identified 4.2% and 0.8% of mutations respectively. BCOR mutations were associated with RUNX1 (P = .002) and DNMT3A mutations (P = .015). BCOR is also mutated in chronic myelomonocytic leukemia patients (7.4%) and BCORL1 in AML patients with myelodysplasia-related changes (9.1%). Using deep sequencing, we show that BCOR mutations arise after mutations affecting genes involved in splicing machinery or epigenetic regulation. In univariate analysis, BCOR mutations were associated with poor prognosis in MDS (overall survival [OS]: P = .013; cumulative incidence of AML transformation: P = .005). Multivariate analysis including age, International Prognostic Scoring System, transfusion dependency, and mutational status confirmed a significant inferior OS to patients with a BCOR mutation (hazard ratio, 3.3; 95% confidence interval, 1.4-8.1; P = .008). These data suggest that BCOR mutations define the clinical course rather than disease initiation. Despite infrequent mutations, BCOR analyses should be considered in risk stratification.

Recurrent mutations in multiple components of the cohesin complex in myeloid neoplasms.

Cohesin is a multimeric protein complex that is involved in the cohesion of sister chromatids, post-replicative DNA repair and transcriptional regulation. Here we report recurrent mutations and deletions involving multiple components of the cohesin complex, including STAG2, RAD21, SMC1A and SMC3, in different myeloid neoplasms. These mutations and deletions were mostly mutually exclusive and occurred in 12.1% (19/157) of acute myeloid leukemia, 8.0% (18/224) of myelodysplastic syndromes, 10.2% (9/88) of chronic myelomonocytic leukemia, 6.3% (4/64) of chronic myelogenous leukemia and 1.3% (1/77) of classical myeloproliferative neoplasms. Cohesin-mutated leukemic cells showed reduced amounts of chromatin-bound cohesin components, suggesting a substantial loss of cohesin binding sites on chromatin. The growth of leukemic cell lines harboring a mutation in RAD21 (Kasumi-1 cells) or having severely reduced expression of RAD21 and STAG2 (MOLM-13 cells) was suppressed by forced expression of wild-type RAD21 and wild-type RAD21 and STAG2, respectively. These findings suggest a role for compromised cohesin functions in myeloid leukemogenesis.

Somatic SETBP1 mutations in myeloid malignancies.

Here we report whole-exome sequencing of individuals with various myeloid malignancies and identify recurrent somatic mutations in SETBP1, consistent with a recent report on atypical chronic myeloid leukemia (aCML). Closely positioned somatic SETBP1 mutations encoding changes in Asp868, Ser869, Gly870, Ile871 and Asp880, which match germline mutations in Schinzel-Giedion syndrome (SGS), were detected in 17% of secondary acute myeloid leukemias (sAML) and 15% of chronic myelomonocytic leukemia (CMML) cases. These results from deep sequencing demonstrate a higher mutational detection rate than reported with conventional sequencing methodology. Mutant cases were associated with advanced age and monosomy 7/deletion 7q (-7/del(7q)) constituting poor prognostic factors. Analysis of serially collected samples indicated that SETBP1 mutations were acquired during leukemic evolution. Transduction with mutant Setbp1 led to the immortalization of mouse myeloid progenitors that showed enhanced proliferative capacity compared to cells transduced with wild-type Setbp1. Somatic mutations of SETBP1 seem to cause gain of function, are associated with myeloid leukemic transformation and convey poor prognosis in myelodysplastic syndromes (MDS) and CMML.

Azacitidine-induced pneumonitis in a patient with myelodysplastic syndrome: first case report in Japan.

A 74-year-old Japanese man with myelodysplastic syndrome (MDS) received chemotherapy with azacitidine. From the second day after starting the administration, he complained of fever, cough and shortness of breath. Chest roentgenography and computed tomography showed consolidations and ground-glass opacities. His symptoms grew from worse to life-threatening. We diagnosed him with azacitidine-induced pneumonitis and began administering corticosteroids. Thereafter, his symptoms and radiographic abnormalities improved. Azacitidine is a hypomethylating agent that improves the survival of MDS patients. Although this drug is commonly well tolerated and rarely causes severe lung injury, it is important to consider the potentially serious adverse effects of azacitidine-induced pneumonitis.

[Extramedullary relapse of acute lymphoblastic leukemia in the breast after unrelated allogeneic bone marrow transplantation].

A 28-year-old female presented with an isolated extramedullary relapse in the breast following an unrelated allogeneic bone marrow transplantation(UBMT)for acute lymphoblastic leukemia. She complained of a tumor in her right breast with hematological complete remission 23 months after her first UBMT. The extramedullary lesion resolved with chemotherapy, and she then received a second UBMT. Although there had been no relapse of leukemia in the bone marrow and extramedullary sites, she died from a herpes simplex virus infection in the central nervous system. Extramedullary relapses in the so-called 'sanctuary'sites after hematopoietic stem cell transplantation are unusual, and breast recurrences are even more rare. A treatment strategy for unusual sites of relapse after BMT should be established.

Frequent pathway mutations of splicing machinery in myelodysplasia.

Myelodysplastic syndromes and related disorders (myelodysplasia) are a heterogeneous group of myeloid neoplasms showing deregulated blood cell production with evidence of myeloid dysplasia and a predisposition to acute myeloid leukaemia, whose pathogenesis is only incompletely understood. Here we report whole-exome sequencing of 29 myelodysplasia specimens, which unexpectedly revealed novel pathway mutations involving multiple components of the RNA splicing machinery, including U2AF35, ZRSR2, SRSF2 and SF3B1. In a large series analysis, these splicing pathway mutations were frequent (∼45 to ∼85%) in, and highly specific to, myeloid neoplasms showing features of myelodysplasia. Conspicuously, most of the mutations, which occurred in a mutually exclusive manner, affected genes involved in the 3'-splice site recognition during pre-mRNA processing, inducing abnormal RNA splicing and compromised haematopoiesis. Our results provide the first evidence indicating that genetic alterations of the major splicing components could be involved in human pathogenesis, also implicating a novel therapeutic possibility for myelodysplasia.

Gain-of-function of mutated C-CBL tumour suppressor in myeloid neoplasms.

Acquired uniparental disomy (aUPD) is a common feature of cancer genomes, leading to loss of heterozygosity. aUPD is associated not only with loss-of-function mutations of tumour suppressor genes, but also with gain-of-function mutations of proto-oncogenes. Here we show unique gain-of-function mutations of the C-CBL (also known as CBL) tumour suppressor that are tightly associated with aUPD of the 11q arm in myeloid neoplasms showing myeloproliferative features. The C-CBL proto-oncogene, a cellular homologue of v-Cbl, encodes an E3 ubiquitin ligase and negatively regulates signal transduction of tyrosine kinases. Homozygous C-CBL mutations were found in most 11q-aUPD-positive myeloid malignancies. Although the C-CBL mutations were oncogenic in NIH3T3 cells, c-Cbl was shown to functionally and genetically act as a tumour suppressor. C-CBL mutants did not have E3 ubiquitin ligase activity, but inhibited that of wild-type C-CBL and CBL-B (also known as CBLB), leading to prolonged activation of tyrosine kinases after cytokine stimulation. c-Cbl(-/-) haematopoietic stem/progenitor cells (HSPCs) showed enhanced sensitivity to a variety of cytokines compared to c-Cbl(+/+) HSPCs, and transduction of C-CBL mutants into c-Cbl(-/-) HSPCs further augmented their sensitivities to a broader spectrum of cytokines, including stem-cell factor (SCF, also known as KITLG), thrombopoietin (TPO, also known as THPO), IL3 and FLT3 ligand (FLT3LG), indicating the presence of a gain-of-function that could not be attributed to a simple loss-of-function. The gain-of-function effects of C-CBL mutants on cytokine sensitivity of HSPCs largely disappeared in a c-Cbl(+/+) background or by co-transduction of wild-type C-CBL, which suggests the pathogenic importance of loss of wild-type C-CBL alleles found in most cases of C-CBL-mutated myeloid neoplasms. Our findings provide a new insight into a role of gain-of-function mutations of a tumour suppressor associated with aUPD in the pathogenesis of some myeloid cancer subsets.

Frequent inactivation of A20 in B-cell lymphomas.

A20 is a negative regulator of the NF-kappaB pathway and was initially identified as being rapidly induced after tumour-necrosis factor-alpha stimulation. It has a pivotal role in regulation of the immune response and prevents excessive activation of NF-kappaB in response to a variety of external stimuli; recent genetic studies have disclosed putative associations of polymorphic A20 (also called TNFAIP3) alleles with autoimmune disease risk. However, the involvement of A20 in the development of human cancers is unknown. Here we show, using a genome-wide analysis of genetic lesions in 238 B-cell lymphomas, that A20 is a common genetic target in B-lineage lymphomas. A20 is frequently inactivated by somatic mutations and/or deletions in mucosa-associated tissue lymphoma (18 out of 87; 21.8%) and Hodgkin's lymphoma of nodular sclerosis histology (5 out of 15; 33.3%), and, to a lesser extent, in other B-lineage lymphomas. When re-expressed in a lymphoma-derived cell line with no functional A20 alleles, wild-type A20, but not mutant A20, resulted in suppression of cell growth and induction of apoptosis, accompanied by downregulation of NF-kappaB activation. The A20-deficient cells stably generated tumours in immunodeficient mice, whereas the tumorigenicity was effectively suppressed by re-expression of A20. In A20-deficient cells, suppression of both cell growth and NF-kappaB activity due to re-expression of A20 depended, at least partly, on cell-surface-receptor signalling, including the tumour-necrosis factor receptor. Considering the physiological function of A20 in the negative modulation of NF-kappaB activation induced by multiple upstream stimuli, our findings indicate that uncontrolled signalling of NF-kappaB caused by loss of A20 function is involved in the pathogenesis of subsets of B-lineage lymphomas.

Molecular cloning of t(2;7)(p24.3;p14.2), a novel chromosomal translocation in myelodysplastic syndrome-derived acute myeloid leukemia.

In this study, we report the molecular structure of the breakpoint region in a new chromosomal translocation, t(2;7)(p24.3;p14.2), in a case of acute myeloid leukemia transformed from myelodysplastic syndrome (MDS). An extensive fluorescence in situ hybridization (FISH) analysis showed that NAG (2p24.3) and ELMO1 (7p14.2) were involved at the breakpoints of t(2;7)(p24.3;p14.2). Furthermore, we detected a novel chimeric transcript consisting of NAG and ELMO1. Interestingly, this transcript encoded a truncated molecular form of 3'ELMO1 as the result of a frameshift caused by the chromosomal translocation. Although this study does not provide direct evidence that a defect in NAG-ELMO1 plays a role in the pathogenesis or the leukemic change in MDS, it does suggest that defects in NAG-ELMO1 potentially contributed to the leukemic progression in this case.

A safety, pharmacokinetic and pharmacodynamic investigation of deferasirox (Exjade, ICL670) in patients with transfusion-dependent anemias and iron-overload: a Phase I study in Japan.

The pharmacokinetics (PK) and pharmacodynamics (PD) of the once-daily, oral ironchelating agent, deferasirox (Exjade, ICL670), have been evaluated further in a Phase I, openlabel, multicenter, dose-escalation study in Japanese patients with myelodysplastic syndromes, aplastic anemia, and other anemias. Deferasirox was initially administered as a single dose of 5 (n = 6), 10 (n = 7), 20 (n = 6) or 30 (n = 7) mg/(kg day) and then after 7 days seven daily doses were administered. Linear PK (C (max) and AUC) were observed at all doses after a single dose and at steady state, and dose-dependent iron excretion was observed. Pharmacokinetic/pharmacodynamic parameters were similar to those reported in a Caucasian beta-thalassemia cohort. Following the single- and multiple-dose phases, 21 of 26 patients progressed to a 3-year extension phase of the study, where dose reductions and increases [5-30 mg/(kg day)] were allowed following safety and efficacy assessments. In the interim, 1-year data show that deferasirox was well tolerated, with generally infrequent and mild adverse events. Reductions in serum ferritin levels were observed and a negative iron balance achieved at doses of 20-30 mg/(kg day). These data suggest that deferasirox has a stable and predictable PK/PD profile, irrespective of underlying disease or race, and a predictable and manageable safety profile suitable for chronic administration.

[Clinical analysis of HLA-DR-negative non-M3 AML].

The type of leukemia was defined as HLA-DR(-) non-M3-AML, when HLA antigens were detected by flow cytometry at an incidence of < 20% of the blast population excluding M3-AML. Out of 109 patients with de novo acute myeloid leukemia, 8 patients had HLA-DR(-) non-AML-M3. According to the French-American-British criteria, 7 patients could be subdivided into 3 patients with M1, 4 patients with M2 and 1 patient with M4. The morphological features of bone marrow aspiration demonstrated no dysplasia and peroxidase stain positivity was noted in over 86% of the blast cells in all patients, the blast cells with fine granularity in 7 patients. The cytogenetic analysis revealed a normal karyotype. There was no expression marker of the blast antigens except CD13, CD14, CD33, CD34 and CD56. All of 7 patients who underwent induction therapy attained complete remission. Overall survival and disease-free survival showed no significant differences between the HLA-DR(-) non- M3-AML group and the HLA-DR(+) AML group.

[Clinical evaluation of biapenem for febrile neutropenia in patients with hematological disorders].

We examined the clinical evaluation of biapenem (BIPM) for febrile neutropenia in patients with hematological disorders. BIPM was administrated by drip infusion when fever developed over 37.5 degrees C with a neutrophil counts lower than 1000/microl. The underlying diseases were acute myelogenous leukemia in 16 cases, acute lymphocytic leukemia in 1, malignant lymphoma in 14, myelodysplastic syndrome in 1, aplastic anemia in 1. Microbiologically documented infections were found in 3 cases (9.1%) before treatment. Clinical effect was excellent in 9 cases, good in 11, fair in 6, poor in 7. Factors associated with efficacy rate were concomitant use of granulocytecolony stimulating factor, duration of neutropenia and neutrophil counts at day 3 of day after start of the therapy. No serious adverse events were observed in all cases, although one case developed exanthema. In conclusion, these results confirmed the efficacy and safety of BIPM for febrile neutropenia in patients with hematological disorders.

[Cord blood transplantation after successful treatment of brain abscess caused by Bacillus cereus in a patient with acute myeloid leukemia].

Central nervous system infection caused by Bacillus cereus is a rare condition, which often progresses rapidly and is fatal in immunocompromised patients. A 54-year-old woman with acute myelogenous leukemia fell into a coma with high fever during severe neutropenia while undergoing chemotherapy. A blood culture demonstrated the presence of B. cereus and magnetic resonance imaging showed multiple abnormal lesions in her brain. The patient was treated with meropenem and vancomycin, and recovered from the coma in a week. Antibiotic therapy was administered for seven weeks, and then she underwent cord blood transplantation for refractory acute myelogenous leukemia with successful engraftment without exacerbation of the brain abscess. This case demonstrates that brain abscess caused by B. cereus can be treated without surgical treatment.

Disseminated intravascular coagulation complicating acute lymphoblastic leukemia: a study of childhood and adult cases.

A high incidence of disseminated intravascular coagulation (DIC) in adult patients with acute lymphoblastic leukemia (ALL) is reported. However, studies comprising both childhood and adult patients are sparse and the clinical relevance of DIC in ALL patients has been a conflicting issue. Coagulation profiles at presentation and within seven days after starting remission-induction therapy of 44 childhood and 51 adult ALL patients were studied. At presentation, two childhood (5%) and 11 adult (22%) patients had DIC (p<0.05). After starting therapy, four of 27 childhood (15%) and 14 of 33 adult (42%) patients screened for coagulopathy developed DIC (p<0.05). Overall, six of the 44 children (14%) and 25 of the 51 adults (49%) were complicated with DIC (p<0.001). In the adult cases, DIC was more frequently complicated with FAB subtype L2 than L1 (p<0.05). All hemorrhages seen in the childhood cases were minor hemorrhages. In the adult patients, two patients with DIC had WHO grade 3 hemorrhage and the other hemorrhagic complications were minor hemorrhages. While milder induction therapies starting with corticosteroid given for childhood cases should be taken into consideration when comparing the incidences of DIC after therapy, the findings indicated that childhood and adult ALL may differ in the procoagulant characteristics. Morphological distinction between L1 and L2 appears to have relevance in the procoagulant activity in adult ALL. DIC complicating ALL is generally mild, however, sometimes causes severe hemorrhages in adults.

[Evaluation of prophylactic use of lamivudine in HBV-positive patients with malignant lymphoma undergoing chemotherapy].

A prospective evaluation was carried out on the effect of lamivudine administration as a prophylactic measure to prevent exacerbation of hepatitis in HBV carrier or chronic hepatitis B patients with malignant lymphoma undergoing chemotherapy. Eighteen patients were registered between 1997 and 2002 from institutions of the Research Group for the Treatment of Malignant Lymphoma. The patients' median age was 53 years old (39-73), and consisted of 8 males and 10 females. HBe-seroconversion had already occurred in 13 and liver biopsy had been performed in 8. No adverse effects of lamivudine were noted and the serum HBV-DNA content did not increase during lamivudine administration. Planned treatment courses could be completed in all patients. In 2, however, the viral load increased and the HBe antibody (Ab) value declined after the cessation of lamivudine, which were reversed to the normal ranges following the resumption of lamivudine. As for the overall outcome, 14 of the patients survived, and there were 4 fatalities due to malignant lymphoma. Serum HBeAb status may be regarded as a useful laboratory marker for deciding the safe cessation of lamivudine. An additional case is described, who had recovered from past HBV infection, but eventually succumbed to fulminant hepatitis after the cessation of lamivudine covering prolonged courses of chemotherapy. This illustrates a need for inclusion of such cases for the prophylactic use of lamivudine.