Michiko Kajiwara

No Advantage of Dexamethasone Over Prednisolone for the Outcome of Standard- and Intermediate-Risk Childhood Acute Lymphoblastic Leukemia in the Tokyo Children's Cancer Study Group L95-14 Protocol

PURPOSE To evaluate whether dexamethasone (DEXA) yields a better outcome than prednisolone (PRED) in a prospective, randomized, controlled trial for the treatment of childhood acute lymphoblastic leukemia (ALL). PATIENTS AND METHODS Two hundred thirty-one standard-risk (SR) patients and 128 intermediate-risk (IR) non-B-cell ALL patients were registered from March 1995 to March 1999. After random assignment in each group, the PRED arm patients received PRED 60 mg/m2 during induction followed by PRED 40 mg/m2 over four intensifications in the SR group and three intensifications in the IR group. DEXA arm patients received DEXA 8 mg/m2 during induction and DEXA 6 mg/m2 during the intensifications. The maintenance phase was continued until week 104. RESULTS Event-free survival rates at 8 years in the DEXA and PRED arms were 81.1% +/- 3.9% (n = 117) and 84.4% +/- 5.2% (n = 114), respectively, in the SR group (P = .217) and 84.9% +/- 4.6% (n = 62) and 80.4% +/- 5.1% (n = 66), respectively, in the IR group (P = .625). The primary reason for treatment failure was marrow relapse. Only two extramedullary relapses occurred in the DEXA arm compared with seven relapses in the PRED arm. Although complications were more prevalent in the DEXA arm than in the PRED arm, fatal toxicity was rare both groups. CONCLUSION DEXA administered at 8 mg/m2 during induction and 6 mg/m2 during intensification showed no advantage over PRED administered at 60 mg/m2 during induction and 40 mg/m2 during intensification in both the SR and IR groups.

Hematopoietic stem cell transplantation for 30 patients with primary immunodeficiency diseases: 20 years experience of a single team.

We retrospectively analyzed our results of 30 patients with three distinctive primary immunodeficiency diseases (PIDs) – severe combined immunodeficiency (SCID, n=11), Wiskott–Aldrich syndrome (WAS, n=11) and X-linked hyper-immunoglobulin M (IgM) syndrome (XHIM, n=8) – who underwent hematopoietic SCT (HSCT) during the past 20 years. Until 1995, all donors were HLA-haploidentical relatives with T-cell depletion (TCD) (n=8). Since 1996, the donors have been HLA-matched related donors (MRD) (n=8), unrelated BM (UR-BM) (n=7) and unrelated cord blood (UR-CB) (n=7). Twenty-seven of 30 patients had various pre-existing infections with or without organ damages before HSCT. Conditioning regimen and GVHD prophylaxis were determined according to disease, donor and pretransplant status. Although one of eight patients transplanted with TCD is alive with full engraftment, the other seven died. On the other hand, 18 of 22 patients transplanted without TCD are alive and well, including six of eight transplanted from MRD, seven of seven from UR-BM and five of seven from UR-CB. All 19 survivors did not require Ig supplementation after HSCT. These results indicate that UR-CBT as well as UR-BMT provides good results for PID comparable to MRD-SCT, and that early diagnosis, HSCT at early stage, careful supportive therapy and monitoring for various pathogens are important for the successful HSCT.

Long-term results of Tokyo Children's Cancer Study Group trials for childhood acute lymphoblastic leukemia, 1984–1999

We report the long-term results of Tokyo Childrens Cancer Study Groups studies L84-11, L89-12, L92-13, and L95-14 for 1846 children with acute lymphoblastic leukemia, which were conducted between 1984 and 1999. The value of event-free survival (EFS)±s.e. was 67.2±2.2% at 10 years in L84-11, which was not improved in the following two studies, and eventually improved to 75.0±1.8% at 10 years in L95-14 study. The lower EFS of the L89-12 reflected a high rate of induction failure because of infection and delayed remission in very high-risk patients. The L92-13 study was characterized by short maintenance therapy; it resulted in poor EFS, particularly in the standard-risk (SR) group and boys. Females did significantly better than males in EFS in the early three studies. The gender difference was not significant in overall survival, partly because >60% of the males survived after the testicular relapse. Randomized studies in the former three protocols revealed that intermediate- or high-dose methotrexate therapy significantly reduced the testicular relapse rate. In the L95-14 study, gender difference disappeared in EFS. Contrary to the results of larger-scale studies, the randomized control study in the L95-14 reconfirmed with updated data that dexamethasone 8 mg/m2 had no advantage over prednisolone 60 mg/m2 in the SR and intermediate-risk groups. Prophylactic cranial irradiation was assigned to 100, 80, 44, and 44% of the patients in the studies, respectively. Isolated central nervous system relapse rates decreased to <2% in the last two trials. Secondary brain tumors developed in 12 patients at 8–22 years after cranial irradiation. Improvement of the remission induction rates and the complete omission of irradiation are currently main objectives in our studies.

Long-term follow-up of childhood acute lymphoblastic leukemia in Tokyo Children's Cancer Study Group 1981-1995.

The objectives were as follows: Firstly, to estimate the overall probability of event-free survival (EFS) and isolated CNS relapse in the studies for children with acute lymphoblastic leukemia (ALL) during the 1980s and 1990s. Secondly, to report the EFS according to presenting features and lineage. Thirdly, to evaluate the treatment results re-classified by the risks of NCI criteria. Four consecutive protocol studies were performed in the Tokyo Childrens Cancer Study Group: L81–10 protocol (1981–1984, 189 patients), L84–11 (1984–1989, 484 patents), L89–12 (1989–1992, 418 patients) and L92–13 (1992–1995, 347 patients). Overall EFS at 5 years in each protocol was 56.5 ± 3.8(1 s.e.)%, 71.0 ± 2.1%, 67.8 ± 2.3%, and 63.4 ± 2.7%, respectively. The cumulative isolated CNS relapse rate at 5 years was 8.1 ± 2.1%, 3.5 ± 0.9%, 3.6 ± 1.0%, 1.0 ± 0.6. The EFS in SR/HR (standard risk/high risk) according to the NCI criteria in B-precursor ALL at 5 years was 61.9 ± 4.3%/41.4 ± 7.4% (lineage was not confirmed.), 72.5 ± 2.6%/63.4 ± 5.0%, 77.4 ± 2.7%/56.3 ± 4.7%, and 67.8 ± 3.4%/56.7 ± 5.4% in each protocol. Also EFSs according to NCI SR/HR at 5 years of T-ALL in protocols L84–11, L89–12 and L92–13 were 55.6 ± 16.6%/60.9 ± 10.1%, 72.7 ± 13.4%/51.6 ± 9.1%, and 77.1 ± 14.4%/53.6/10.1%, respectively. The truncation of maintenance therapy to 6 months resulted in a decreased EFS in L92–13, particularly due to an increase of bone marrow relapse after cessation of therapy in SR and HR. The NCI risk criteria work properly even in the patients treated by different intensities, so that it makes the comparison possible among the patients in various groups. The overall EFSs in childhood ALL improved in 1980s, but it seemed stable or decreased in 1990s. The short maintenance therapy resulted in poor outcome in SR on the L92–13 protocol. Many of these late relapsers were effectively rescued and overall survival remained at a high level. The proportion of patients who received cranial irradiation reduced without any increase of the CNS events.

Increased sensitivity for detection of human cytomegalovirus in urine by removal of inhibitors for the polymerase chain reaction

The presence of inhibitors in urine interferes with the enzymatic reaction of the polymerase chain reaction (PCR) for detection of human cytomegalovirus (HCMV). To remove inhibitors, HCMV virions in urine were precipitated with polyethylene glycol, or DNA was extracted from urine by the use of glass powder and subjected to PCR followed by Southern blot hybridization with alkaline phosphatase-linked oligonucleotide probes. These simple, rapid methods increased significantly the sensitivity of PCR for detection of HCMV in urine.

Outcome of unrelated umbilical cord blood transplantation in 88 patients with primary immunodeficiency in Japan

We report the results of umbilical cord blood transplantation (UCBT) performed in 88 patients with primary immunodeficiency (PID) between 1998 and 2008 in Japan; severe combined immunodeficiency (SCID, n = 40), Wiskott–Aldrich syndrome (WAS, n = 23), chronic granulomatous disease (n = 7), severe congenital neutropaenia (SCN, n = 5) and other immunodeficiencies (n = 13). Five‐year overall survival (5‐year OS) for all patients was 69% [95% confidence interval (CI), 57–78%], and was 71% and 82% for SCID and WAS, respectively. The main cause of death before day 100 was infection (17/19), while that after day 100 was graft‐versus‐host disease (GVHD) (5/7). Using multivariate analyses, pre‐transplant infection, no conditioning, ≥2 human leucocyte antigen (HLA) mismatches or diagnosis other than SCID, SCN or WAS were all associated with poor prognosis. Reduced‐intensity conditioning was associated with decreased overall mortality compared with myeloablative therapy. The cumulative incidence of grade 2–4 acute GVHD at day 100 was 28% (95% CI, 19–38%), and that of chronic GVHD at day 180 was 13% (95% CI, 7–23%). We conclude that UCBT should be considered for PID patients without an HLA‐matched sibling. The control of pre‐transplant infection and selection of HLA‐matched donors will lead to a better outcome.

Novel adopted immunotherapy for mixed chimerism after unrelated cord blood transplantation in Omenn syndrome.

Abstract:  Omenn syndrome is a variant form of severe combined immunodeficiency. It is fatal unless treated by allogeneic stem cell transplantation (SCT), which is the only curative approach. However, both treatment‐related complications and graft rejection are major obstacles to treatment success. This report describes a case with Omenn syndrome who developed mixed chimerism after unrelated cord blood transplantation (UCBT). This case was successfully treated by altering the patients immunosuppression and donor lymphocyte infusion (DLI) with donor cord blood‐derived activated CD4+ T cells ex vivo expanded from the cord blood cell residues in an infused bag. This novel development to expand CD4+ T‐lymphocytes from the donor cord blood unit for the use of DLI would serve as a useful method to overcome the risk of graft rejection in SCT for primary immunodeficiency disorders with residual cell‐mediated immunity without compounding graft‐vs.‐host disease, especially in the UCBT setting.

WASP is involved in proliferation and differentiation of human haemopoietic progenitors in vitro

The Wiskott‐Aldrich syndrome (WAS) is an X‐linked recessive disorder characterized by thrombocytopenia, immunodeficiency and eczema. X‐linked thrombocytopenia (XLT) is a mild form of WAS with isolated thrombocytopenia. Both phenotypes are caused by mutation of the Wiskott‐Aldrich syndrome protein (WASP) gene. In this study we investigated the role of WASP in the differentiation of CD34‐positive (CD34+) cells isolated from the bone marrow of patients with WAS (n = 5) or with XLT (n = 4). Megakaryocyte colony formation was significantly decreased in patients with WAS when compared with normal controls. The formation of granulocyte‐macrophage colonies and erythroid bursts were also decreased in WAS patinets. In contrast, in XLT patients, formation of all these colonies was normal. However, in vitro proplatelet formation of megakaryocytes induced by thrombopoietin was markedly decreased in both XLT and WAS. Electron microscopic examination revealed that megakaryocytes obtained from WAS or XLT patients grown in vitro had abnormal morphologic features, which seemed to be caused by defective actin cytoskeletal organization, including labyrinth‐like structures of the demarcation membrane system and deviated distribution of the α‐granules and demarcation membrane system. These observations indicate that WASP is involved in the proliferation and differentiation of CD34+ haemopoietic progenitor cells probably by its participation in signal transduction and in the regulation of the cytoskeleton.

A recombinant human ADAMTS-13: first-in-human study evaluating pharmacokinetics, safety and tolerability in cTTP patients.

Safety, tolerability, and pharmacokinetics of recombinant ADAMTS-13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13; BAX 930; SHP655) were investigated in 15 patients diagnosed with severe congenital ADAMTS-13 deficiency (plasma ADAMTS-13 activity <6%) in a prospective phase 1, first-in-human, multicenter dose escalation study. BAX 930 was well tolerated, no serious adverse events occurred, and no anti-ADAMTS-13 antibodies were observed. After single-dose administration of BAX 930 at 5, 20, or 40 U/kg body weight to adolescents and adults, there was approximate dose proportionality with respect to maximum plasma concentration (Cmax [U/mL]) and area under the concentration-time curve (AUC [h∙U/mL]). Dose-related increases of individual ADAMTS-13:Ag and activity were observed and reached a maximum within 1 hour. With escalating BAX 930 doses administered, a dose-dependent persistence of ADAMTS-13-mediated von Willebrand factor (VWF) cleavage products and reduced VWF multimeric size were observed. This study demonstrated that pharmacokinetic parameters of BAX 930 were comparable to those estimated in previous plasma infusion studies and provided evidence of pharmacodynamic activity. This study was registered at www.clinicaltrials.gov as #NCT02216084.

Haploinsufficiency of TNFAIP3 (A20) by germline mutation is involved in autoimmune lymphoproliferative syndrome

Background Autoimmune diseases in children are rare and can be difficult to diagnose. Autoimmune lymphoproliferative syndrome (ALPS) is a well‐characterized pediatric autoimmune disease caused by mutations in genes associated with the FAS‐dependent apoptosis pathway. In addition, various genetic alterations are associated with the ALPS‐like phenotype. Objective The aim of the present study was to elucidate the genetic cause of the ALPS‐like phenotype. Methods Candidate genes associated with the ALPS‐like phenotype were screened by using whole‐exome sequencing. The functional effect of the identified mutations was examined by analyzing the activity of related signaling pathways. Results A de novo heterozygous frameshift mutation of TNF‐&agr;–induced protein 3 (TNFAIP3, A20), a negative regulator of the nuclear factor &kgr;B pathway, was identified in one of the patients exhibiting the ALPS‐like phenotype. Increased activity of the nuclear factor &kgr;B pathway was associated with haploinsufficiency of TNFAIP3 (A20). Conclusion Haploinsufficiency of TNFAIP3 (A20) by a germline heterozygous mutation leads to the ALPS phenotype.