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Objectives Although epidemiological surveys of paediatric rheumatic diseases in Japan have been conducted, they were single surveys with no continuity. This is the first report of the Pediatric Rheumatology Association of Japan registry database, which was established to continuously collect data for paediatric rheumatic diseases. Methods Pediatric Rheumatology International Collaborate Unit Registry version 2 (PRICUREv2) is a registry database established by the Pediatric Rheumatology Association of Japan. The registry data were analysed for the age of onset, time to diagnosis, sex differences, seasonality, and other factors. Results Our data showed the same trend regarding rates of paediatric rheumatic diseases reported in Japan and other countries. The age of onset was lower in juvenile idiopathic arthritis (JIA) and juvenile dermatomyositis and higher in systemic lupus erythematosus and Sjögren’s syndrome. The time to diagnosis was relatively short in JIA and systemic lupus erythematosus but longer in juvenile dermatomyositis and Sjögren’s syndrome. Rheumatoid factor-positive polyarticular JIA showed a seasonality cluster with regard to onset. Conclusion PRICUREv2 aided the retrieval and evaluation of current epidemiological information on patients with paediatric rheumatic diseases. It is expected that the data collection will be continued and will be useful for expanding research in Japan.

Introduction A simple indicator of muscle damage is creatine kinase (CK). Although CK elevation is informative for malignant hyperthermia, no study has examined the relationship between the anesthetically awake state and CK in children. We aimed to prospectively examine the relationship between the awakening state and CK on the day after surgery in children who have undergone anesthesia with volatile inhalation anesthetics. Methods The study included 119 patients aged 0-15 years and scheduled to undergo general anesthesia for cleft lip and palate-related surgery. Emergence agitation (EA) was assessed after completion of general anesthesia using the five-point EA scale, and patients were divided into the following five groups according to the EA score: EA1, EA2, EA3, EA4, and EA5. The primary outcome was ΔCK (comparison of CK values one week prior to surgery to CK values on the day after surgery) in each EA group. The secondary outcome was ΔCK when the EA score was divided into the following two groups: EA ≤2 (EA score of 1 or 2) and EA ≥3 (EA score of 3, 4, or 5). Results The median ΔCK values in the EA1 to EA5 groups were 3 (quartile -19~9), 5 (-32~88), 99.5 (-18~190.5), 121 (29~219.5), and 144 (41~340.5), respectively, indicating a statistically significant difference overall. Statistically significant differences were also observed between the EA1 and EA4 groups and between the EA2 and EA4 groups. The median ΔCK values in the EA ≤2 and EA ≥3 groups were 3 (quartile -27~85) and 108 (23.5~206.7), respectively, indicating a statistically significant difference. Conclusion The results of this study revealed that a higher EA score at the time of anesthesia awakening is associated with a larger ΔCK, indicating that a high CK level on the day after surgery is highly related to the state of the patient upon awakening.

Objective To describe the clinical characteristics, treatment, and outcomes of a multinational cohort of patients with macrophage activation syndrome (MAS) and thrombotic microangiopathy (TMA). Study design International pediatric rheumatologists were asked to collect retrospectively the data of patients with the co-occurrence of MAS and TMA. Clinical and laboratory features of patients with systemic juvenile idiopathic arthritis (sJIA)-associated MAS and TMA were compared with those of an historical cohort of patients with sJIA and MAS. Results Twenty-three patients with MAS and TMA were enrolled: 17 had sJIA, 2 systemic lupus erythematosus, 1 juvenile dermatomyositis, 1 mixed connective tissue disease, and 2 undifferentiated connective tissue disease. Compared with the historical cohort of MAS, patients with sJIA with coexistent MAS and TMA had higher frequencies of renal failure and neurologic involvement, hemorrhage, jaundice, and respiratory symptoms, as well as more severe anemia and thrombocytopenia, higher levels of alanine aminotransferase, lactate dehydrogenase, bilirubin and D-dimer, and lower levels of albumin and fibrinogen. They also required admission to the intensive care unit more frequently. Among patients tested, complement abnormalities and reduced ADAMTS13 activity were observed in 64.3% and 44.4% of cases, respectively. All patients received glucocorticoids. Treatment for TMA included plasma-exchange, eculizumab, and rituximab. Conclusions The possible coexistence of MAS and TMA in rheumatic diseases may be underrecognized. This association should be considered in patients with MAS who develop disproportionate anemia, thrombocytopenia, and lactate dehydrogenase increase, or have multiorgan failure.

Kawasaki disease (KD) is a febrile disease of childhood characterized by systemic vasculitis that can lead to coronary artery lesions (CAL). This was a prospective cohort study to determine the levels of the pentraxin 3 (PTX3), soluble CD24-Subtype (Presepsin) and N-terminal pro-brain natriuretic peptide (NT-pro BNP) in consecutive KD patients. From January 2013 to March 2015, all patients with KD admitted to Aichi Medical University Hospital who provided consent had their plasma saved before IVIG administration. In total, 97 cases were registered. 22 cases of incomplete KD were excluded from the outcome analysis. The total 75 cases were used for statistical analyses. A PTX3 threshold of >7.92 ng/ml provided a specificity of 88.5 %, a sensitivity of 94.4 %, and a likelihood ratio as high as 15.92 for the diagnosis of KD compared with febrile non-KD controls. Although an echocardiographic diagnosis of CAL in the early course of the disease was confirmed in 24 cases, it was not in the remaining 51 cases. Neither NT-proBNP nor Presepsin had statistical significance for the prediction of the echocardiographic CAL diagnosis. Only PTX3 was significantly predictive of the echocardiographic CAL diagnosis (p=0.01). The PTX3 level was significantly higher in the intravenous immunoglobulin (IVIG) non-responders (45.9±7.45) than in the IVIG responders (17.0 ± 1.46 ng/ml) (p< 0.001). The PTX3 level also correlated with the number of IVIG treatment courses needed to resolve fever (R² =0.64). Persistent CAL (pCAL) formation was observed in three cases; one of aneurysm only and two aneurysms with dilatations. The patients with pCAL had significantly higher PTX3 levels (85 ± 8.4 ng/ml) than patients without pCAL (22 ± 2.2 ng/ml) (p< 0.0001). In terms of pCAL prediction, the area under the curve (AUC) of receiver operating characteristic ROC curve of PTX3 was 0.99, and it was significantly greater than that of Presepsin (0.67) or NT-proBNP (0.75). PTX3 is a soluble pattern recognition molecule that acts as a main component of the innate immune system. These data suggest that PTX3 can be utilized as a definitive biomarker for the prediction of IVIG resistance and subsequent CAL formation in patients with KD.

Langerhans cell histiocytosis (LCH) with single-system (SS) multifocal bone (MFB) lesions is rarely fatal, but patients may experience relapses and develop LCH-associated sequelae. To evaluate effect on outcomes of pediatric multifocal LCH, we tested a treatment protocol modified from the Japan Langerhans Cell Histiocytosis Study Group (JLSG)-96 study. We assessed the outcomes of all consecutive newly diagnosed pediatric patients with LCH with SS-MFB lesions who were treated with JLSG-02 protocol in 2002-2009. JLSG-02 was modified from JLSG-96 as follows: increased prednisolone dosage at the induction phase and extension of maintenance therapy duration from 24 to 48 weeks. In total, 82 patients with a median follow-up duration of 8.0 years were eligible for analysis. At 6 weeks, 92.7% responded to induction; however, 27.6% of responders experienced relapses. In total, 4.8% developed central nervous system-related sequelae, including central diabetes insipidus and neurodegeneration, which were associated with relapse. None of the patients died. The 5-year event-free survival rates were not different between JLSG-02 and -96 cohort (66.7 vs. 65.1%; p = 0.697). Modification of previous treatment protocol did not contribute to improvement of outcomes in LCH with SS-MFB lesions.

Objective To describe the clinical, laboratory, and histopathologic features, current treatment, and outcome of patients with macrophage activation syndrome (MAS) complicating systemic juvenile idiopathic arthritis (JIA). Methods In this multinational, multicenter study, pediatric rheumatologists and hemato-oncologists entered patient data collected retrospectively into a web-based database. Results A total of 362 patients, 22% of whom had MAS at the onset of systemic JIA, were included in the study by 95 investigators from 33 countries. The most frequent clinical manifestations were fever (96%), hepatomegaly (70%), and splenomegaly (58%). Central nervous system dysfunction and hemorrhages were recorded in 35% and 20% of the patients, respectively. Platelet count and liver transaminase, ferritin, lactate dehydrogenase, triglyceride, and d-dimer levels were the sole laboratory biomarkers showing a percentage change of >50% between the pre-MAS visit and MAS onset. Evidence of macrophage hemophagocytosis was found in 60% of the patients who underwent bone marrow aspiration. MAS occurred most frequently in the setting of active underlying disease, in the absence of a specific trigger. Nearly all patients were given corticosteroids, and 61% received cyclosporine. Biologic medications and etoposide were given to 15% and 12% of the patients, respectively. Approximately one-third of the patients required admission to the intensive care unit (ICU), and the mortality rate was 8%. Conclusion This study provides information on the clinical spectrum and current management of systemic JIA–associated MAS through the analysis of a very large patient sample. MAS remains a serious condition, as a sizeable proportion of patients required admission to the ICU or died.

Background Hematopoietic stem cell transplantation (HSCT) is one curable option for high-risk acute lymphoblastic leukemia (ALL); however, transplant-related toxicities might be severe in patients with Down syndrome and ALL (DS-ALL). Procedure HSCTs performed in patients with DS-ALL were identified in the Japan Society for Hematopoietic Cell Transplantation registry. Results In the registry data, 11 patients with DS-ALL were identified. The median age at HSCT was 9 years (range: 6–22 years). Six patients underwent HSCT at non-remission status. Allogeneic grafts were utilized in all patients, including eight patients who received HSCT from unrelated donors. Reduced intensity conditioning regimens were used in three patients. All patients achieved neutrophil engraftment by a median of day 18 (range: day 11–61). Ten patients experienced grade 3 or more infectious episodes. Six patients experienced complications of the respiratory system. The incidences of II–IV or III–IV acute GVHD were nine (81.8%) or seven patients (63.6%), respectively. Chronic GVHD was observed in five (55.6%) out of nine evaluable patients. Seven patients died at a median of 6 months (range: 0–24 months) after HSCT. Two-year relapse-free and overall survival were 33.3% (95% CI: 2.5–64.1%) or 37.5% (95% CI: 5.9–69.1%), respectively. The causes of death were relapse (n = 2), infection (n = 2), bleeding (n = 1), thrombotic microangiopathy (n = 1), and chronic GVHD (n = 1). Conclusions Therapy-related mortality accounted for five out of seven deceased patients in this case series. Attempts to reduce toxicities should be considered in HSCT for patients with DS-ALL. Pediatr Blood Cancer 2015;62:148–152. © 2014 Wiley Periodicals, Inc.

Background Chediak–Higashi syndrome (CHS) is a rare autosomal recessive disorder characterized by immunodeficiency, neurological dysfunction, and oculocutaneous albinism. Recently, several clinical CHS phenotypes have been reported. Here, we report results of a nationwide survey performed to clarify clinical characteristics and outcomes of CHS patients in Japan. Methods Questionnaires were sent to 287 institutions to collect data regarding CHS patients diagnosed between 2000 and 2010, including results of lysosomal trafficking regulator (LYST) gene analysis. Cytotoxicity and degranulation activity of cytotoxic T lymphocytes were analyzed in available patient samples. Results A total of 15 patients diagnosed with CHS were eligible for enrollment in this study. Of these, 10 (67%) had recurrent bacterial infections, five (33%) developed life-threatening hemophagocytic lymphohistiocytosis (HLH), and one patient had complicated malignant lymphoma. Hematopoietic stem cell transplantation (HSCT) was performed for six patients including three with HLH, and 10 of the enrolled patients have survived at the time of this writing. LYST analysis was performed for 10 patients; seven different mutations were detected in seven patients, whereas no mutation was identified in three patients. Cytotoxicity and degranulation activity were impaired in patients with and without LYST mutation. Discussion Results of this survey indicate that one or two patients with CHS were newly diagnosed each year in Japan. The incidence of HLH was not as high as expected. Mutations of genes other than LYST were suspected in some cases. We conclude that determining indication for HSCT for CHS patients should be based on genetic and cytotoxic analysis. Pediatr Blood Cancer 2013;60:1582–1586. © 2013 Wiley Periodicals, Inc.

Background Peripheral blood stem cells (PBSC) may be used as an alternative to bone marrow (BM) for allogeneic transplantation. Since peripheral blood stem cell bank from unrelated volunteer donor has been started in Japan, use of PBSC allografts may be increased. Therefore we surveyed the outcomes of Japanese leukemia children after PBSC and BM transplantation. Procedure This retrospective study compared the outcomes of 661 children (0–18 years) with acute lymphoblastic leukaemia (ALL) or acute myeloid leukaemia (AML) who received their first allogeneic peripheral blood stem cell transplantation (PBSCT; n = 90) or bone marrow transplantation (BMT; n = 571) from HLA-matched siblings between January 1996 and December 2007. Result Neutrophil recovery was faster after PBSCT than after BMT (ALL: P

OBJECTIVE: To develop and validate a diagnostic score that assists in discriminating primary hemophagocytic lymphohistiocytosis (pHLH) from macrophage activation syndrome (MAS) related to systemic juvenile idiopathic arthritis. STUDY DESIGN: The clinical, laboratory, and histopathologic features of 362 patients with MAS and 258 patients with pHLH were collected in a multinational collaborative study. Eighty percent of the population was assessed to develop the score and the remaining 20% constituted the validation sample. Variables that entered the best fitted model of logistic regression were assigned a score, based on their statistical weight. The MAS/HLH (MH) score was made up with the individual scores of selected variables. The cutoff in the MH score that discriminated pHLH from MAS best was calculated by means of receiver operating characteristic curve analysis. Score performance was examined in both developmental and validation samples. RESULTS: Six variables composed the MH score: age at onset, neutrophil count, fibrinogen, splenomegaly, platelet count, and hemoglobin. The MH score ranged from 0 to 123, and its median value was 97 (1st-3rd quartile 75-123) and 12 (1st-3rd quartile 11-34) in pHLH and MAS, respectively. The probability of a diagnosis of pHLH ranged from 99% for a score of =123. A cutoff value of =60 revealed the best performance in discriminating pHLH from MAS. CONCLUSION: The MH score is a powerful tool that may aid practitioners to identify patients who are more likely to have pHLH and, thus, could be prioritized for functional and genetic testing.

Objective To develop criteria for the classification of macrophage activation syndrome (MAS) in patients with systemic juvenile idiopathic arthritis (JIA). Methods A multistep process, based on a combination of expert consensus and analysis of real patient data, was conducted. A panel of 28 experts was first asked to classify 428 patient profiles as having or not having MAS, based on clinical and laboratory features at the time of disease onset. The 428 profiles comprised 161 patients with systemic JIA-associated MAS and 267 patients with a condition that could potentially be confused with MAS (active systemic JIA without evidence of MAS, or systemic infection). Next, the ability of candidate criteria to classify individual patients as having MAS or not having MAS was assessed by evaluating the agreement between the classification yielded using the criteria and the consensus classification of the experts. The final criteria were selected in a consensus conference. Results Experts achieved consensus on the classification of 391 of the 428 patient profiles (91.4%). A total of 982 candidate criteria were tested statistically. The 37 best-performing criteria and 8 criteria obtained from the literature were evaluated at the consensus conference. During the conference, 82% consensus among experts was reached on the final MAS classification criteria. In validation analyses, these criteria had a sensitivity of 0.73 and a specificity of 0.99. Agreement between the classification (MAS or not MAS) obtained using the criteria and the original diagnosis made by the treating physician was high (κ = 0.76). Conclusion We have developed a set of classification criteria for MAS complicating systemic JIA and provided preliminary evidence of its validity. Use of these criteria will potentially improve understanding of MAS in systemic JIA and enhance efforts to discover effective therapies, by ensuring appropriate patient enrollment in studies.

L-Asparaginase (ASNase) is important for the treatment of childhood acute lymphoblastic leukemia. ASNase sensitivity has been shown to correlate with the asparagine synthetase (ASNS) protein content in acute lymphoblastic leukemia cell lines. However, there have been few studies to determine ASNS protein levels in human leukemias, since no appropriate monoclonal antibody is available for such quantitative analysis. In this study, we report the generation of anti-ASNS monoclonal antibodies, which are applicable to flow cytometry and enzyme-linked immunosorbent assay. These monoclonal antibodies should provide a valuable tool for the quantification of ASNS protein level and estimation of ASNase-resistance in leukemia cells.

Fifty percent of Diamond-Blackfan anemia (DBA) patients possess mutations in genes coding for ribosomal proteins (RPs). To identify new mutations, we investigated large deletions in the RP genes RPL5, RPL11, RPL35A, RPS7, RPS10, RPS17, RPS19, RPS24, and RPS26. We developed an easy method based on quantitative-PCR in which the threshold cycle correlates to gene copy number. Using this approach, we were able to diagnose 7 of 27 Japanese patients (25.9%) possessing mutations that were not detected by sequencing. Among these large deletions, similar results were obtained with 6 of 7 patients screened with a single nucleotide polymorphism array. We found an extensive intragenic deletion in RPS19, including exons 1-3. We also found 1 proband with an RPL5 deletion, 1 patient with an RPL35A deletion, 3 with RPS17 deletions, and 1 with an RPS19 deletion. In particular, the large deletions in the RPL5 and RPS17 alleles are novel. All patients with a large deletion had a growth retardation phenotype. Our data suggest that large deletions in RP genes comprise a sizable fraction of DBA patients in Japan. In addition, our novel approach may become a useful tool for screening gene copy numbers of known DBA genes.

The objectives of this study are to clarify (1) the difference in demographic and clinical variables at initial presentation between acute and chronic idiopathic thrombocytopenic purpura (ITP), and (2) the prognostic factors of patients with chronic ITP. We conducted a retrospective analysis of 247 children with newly diagnosed ITP between April 1991 and March 2006 who visited one of the 12 hospitals belonging to the Kyoto University Pediatric Hematologic Study Group. 180 and 67 cases were classified as the acute type and as the chronic type, respectively. Older age, higher initial platelet count, positive medical history or concomitant medical diagnosis, the absence of preceding infection or vaccination, and the absence of an increase in immunoglobulin were risk factors for the chronicity. The prognostic factors in chronic ITP were evaluated in 53 patients after excluding patients receiving splenectomy or having insufficient follow-up data. The overall time required for 50% resolution in patients with chronic ITP was approximately 5.6 years. Age at presentation of less than 3 years and higher platelet counts at the time of chronic ITP diagnosis were good prognostic factors. On the other hand, gender, initial platelet counts, and preceding infection or vaccination were not associated with the prognosis.

Langerhans cell histiocytosis (LCH) can be a single system or multi-system disease. Both disease types can be associated with multi-focal bone lesions, but their bone involvement patterns have not been compared systematically. Of the new pediatric LCH cases enrolled into the JLSG-02 study during 2002–2007, 67 cases of single system multifocal bone (SMFB) LCH and 97 cases of multi-system bone (MSB) LCH were analyzed to determine if the bone involvement patterns differ in these two types, and whether these differences correlate with outcome. Statistical analysis was performed with Mann–Whitney U test, Fisher’s exact test, and other measures. Onset ages were higher for SMFB (P < 0.001), but the two types did not differ in the number of bone lesions per patient. The skull was most frequently affected in both types, followed by the spine. Lesions in the temporal bone (P = 0.002), ear-petrous bone (P < 0.001), orbita (P = 0.003), and zygomatic bone (P = 0.016) were significantly more common in MSB. The two types did not differ in response to treatment, but MSB was associated with a significantly higher incidence of diabetes insipidus (DI) (P < 0.001). Novel measures are required in preventing the development of DI in MSB-type LCH patients with “risk” bone lesions.

A 66-year-old Japanese woman was referred to us because of severe anemia and fever and presented at our hospital. She was eventually diagnosed as having acute myeloblastic leukemia (AML; M0) with non-Hodgkin lymphoma (NHL). We investigated the therapeutic efficacy of L-asparaginase (L-Asp), vincristine and prednisolone for both her AML and NHL. Asparagine synthetase (AS) activity in her AML blast cells was undetectable. A lymph node biopsy specimen revealed NHL of the marginal zone B cell type. Complete remission (CR) of AML and NHL was achieved. CR of the AML lasted for 18 months without further consolidation therapy. We conclude that L-Asp can be an effective drug for the treatment of AML in which blasts are negative for AS.

Although vascular inflammation is an important feature of Kawasaki disease (KD), the usefulness of local inflammatory markers as biomarkers for KD is unknown. Pentraxin 3 (PTX3), soluble lectin-like oxidized low density lipoprotein receptor 1 (sLOX-1) and matrix metraloproteinase-9 (MMP-9) are biomarkers of inflammation of vascular components. Objective: We tested whether plasma concentrations of PTX3, sLOX-1 or MMP-9 would be a useful biomarker for detecting high risk patient of coronary artery aneurysm (CAA) in KD and compared with serum level of interleukin-6 (IL-6) and IL-18. The ability of the assays to identify KD patients at risk for CAA was analyzed. Methods: PTX3, sLOX-1, MMP-9, IL-6 and IL-18 concentrations of 50 KD patients at different four clinical points were analyzed. Point A represented on admission; B, pre-IVIG; A+B, before IVIG; C, after IVIG; D, after fever resolution. Each concentration was compared with the rate of occurrence of CAA and IVIG unresponsiveness. Results: Each value was evaluated in 50 KD patients (2 with CAA, 48 without CAA). Three patients were treated without IVIG, 17 with one course of IVIG, and six with two IVIGs, two with three IVIGs, respectively. At the points A+B, C, D means for PTX3 were; 33.4, 11.7, 9.00 ng/ml, mean for MMP-9; 34.6, 19.2, 24.2 ng/ml, mean for sLOX-1; 3.82, 2.33, 2.25 ng/ml, respectively. Levels of PTX3 (p

We examined the effectiveness of various anti-tumour agents to natural killer (NK)-cell tumour cell lines and samples, which are generally resistant to chemotherapy, using flow cytometric terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labelling (TUNEL) assay. Although NK-YS and NK-92 were highly resistant to various anti-tumour agents, l-asparaginase induced apoptosis in these two NK-cell lines. NK-cell leukaemia/lymphoma and acute lymphoblastic leukaemia (ALL) samples were selectively sensitive to l-asparaginase and to doxorubicin (DXR) respectively. Samples of chronic NK lymphocytosis, an NK-cell disorder with an indolent clinical course, were resistant to both drugs. Our study clearly separated two major categories of NK-cell disorders and ALL according to the sensitivity to DXR and l-asparaginase. We examined asparagine synthetase levels by real-time quantitative polymerase chain reaction (RQ-PCR) and immunostaining in these samples. At least in nasal-type NK-cell lymphoma, there was a good correlation among asparagine synthetase expression, in vitro sensitivity and clinical response to l-asparaginase. In aggressive NK-cell leukaemia, although asparagine synthetase expression was high at both mRNA and protein levels, l-asparaginase induced considerable apoptosis. Furthermore, samples of each disease entity occupied a distinct area in two-dimensional plotting with asparagine synthetase mRNA level (RQ-PCR) and in vitrol-asparaginase sensitivity (TUNEL assay). We confirmed rather specific anti-tumour activity of l-asparaginase against NK-cell tumours in vitro, which provides an experimental background to the clinical use of l-asparaginase for NK-cell tumours.

We established a real-time quantitative PCR (RQ-PCR) with which to measure abundance of the asparagine synthetase (AS) mRNA. The level of AS mRNA paralleled AS enzyme activity, as well as the AS protein level detected by Western blotting and by in situ immunostaining. Cytotoxicity tests in vitro showed that the AS mRNA level also synchronized with cellular resistance to L-asparaginase in cell lines. Cellular levels of AS enzyme activity correlated with resistance to L-asparaginase. These results indicate that the AS mRNA level is an index of resistance to L-asparaginase. RQ-PCR is superior to enzyme assays, Western blotting, and immunostaining in the following ways: less labor and time, accurate and reproducible quantitativity, and broad dynamic range. In addition, RQ-PCR could evaluate differences in L-asparaginase sensitivity although immunostaining could not. And in clinical samples, we analyzed eight pediatric leukemia cases by this RQ-PCR to evaluate whether this method was applicable to clinical laboratories and the expression level of AS mRNA in each case were predictable for the effectiveness of L-asparaginase treatment. Consequently, this method was useful enough in defining candidates for selective therapy that targets an AS deficiency.

A 2-year-old Japanese boy who presented with multiple cervical, axillary, and inguinal lymphadenopathy was diagnosed by immunocytochemical analysis as having myeloid/natural killer (NK) cell precursor acute leukemia. Leukemic blasts in the bone marrow were positive for CD56 (NK marker), CD7 (T-cell marker), CD33 (myeloid marker), CD34, and HLA-DR. Tumor cells in a lymph node were also positive for CD2, cytoplasmic CD3 (T-cell marker), CD7, CD33, CD34, and CD56, but negative for peroxidase staining and other T-cell, NK, and myeloid markers. Southern blot analysis showed no rearrangement bands for T-cell receptor delta and immunoglobulin heavy chain. Chromosomal analysis revealed 46,XY,inv(7)(p21q21). Neither chemotherapy for acute lymphoblastic leukemia nor that for acute myeloid leukemia induced remission in this patient. However, complete remission was achieved by the administration of L-asparaginase (6,000 U/m2 for 5 days). Because the disease was considered refractory to standard chemotherapy, cord blood transplantation was performed from an HLA 1-locus mis-matched unrelated donor. The conditioning regimen consisted of total body irradiation, cytarabine, and cyclophosphamide, and cyclosporine and short-term methotrexate were employed for graft-versus-host disease (GVHD) prophylaxis. Hematological reconstitution was rapid, and only grade I acute GVHD was observed. The patient has been in remission for more than 24 months after transplantation. Our findings indicate that combination therapy with L-asparaginase and allogeneic stem cell transplantation may be useful for the treatment of myeloid/NK cell precursor acute leukemia.

The authors report 2 male patients with dyskeratosis congenita (DC) in a Japanese kindred. Sequencing of the complementary DNA of the dyskerin gene (DKC1) revealed a T-to-C transition at nucleotide 1285 in exon 12 that resulted in a novel missense mutation L398P. Despite harboring the same mutation in the DKC1 gene, one patient had significantly milder hematological symptoms than the other, indicating that there may be other factors that determine the severity of DC.

Hematopoietic stem cell transplantation (HSCT) is one curable option for high-risk acute lymphoblastic leukemia (ALL); however, transplant-related toxicities might be severe in patients with Down syndrome and ALL (DS-ALL).HSCTs performed in patients with DS-ALL were identified in the Japan Society for Hematopoietic Cell Transplantation registry.In the registry data, 11 patients with DS-ALL were identified. The median age at HSCT was 9 years (range: 6-22 years). Six patients underwent HSCT at non-remission status. Allogeneic grafts were utilized in all patients, including eight patients who received HSCT from unrelated donors. Reduced intensity conditioning regimens were used in three patients. All patients achieved neutrophil engraftment by a median of day 18 (range: day 11-61). Ten patients experienced grade 3 or more infectious episodes. Six patients experienced complications of the respiratory system. The incidences of II-IV or III-IV acute GVHD were nine (81.8%) or seven patients (63.6%), respectively. Chronic GVHD was observed in five (55.6%) out of nine evaluable patients. Seven patients died at a median of 6 months (range: 0-24 months) after HSCT. Two-year relapse-free and overall survival were 33.3% (95% CI: 2.5-64.1%) or 37.5% (95% CI: 5.9-69.1%), respectively. The causes of death were relapse (n = 2), infection (n = 2), bleeding (n = 1), thrombotic microangiopathy (n = 1), and chronic GVHD (n = 1).Therapy-related mortality accounted for five out of seven deceased patients in this case series. Attempts to reduce toxicities should be considered in HSCT for patients with DS-ALL.

Colorectal cancer during pregnancy is very rare. We report two additional cases of rectal carcinoma. A 34-year-old woman with an obstructive adenocarcinoma of the rectal region was diagnosed at labor. A 35-year-old woman with an adenocarcinoma of the rectal region was diagnosed at 32 weeks of gestation and underwent a cesarean section and rectal resection at 35 weeks of gestation. A retrospective review of the Japanese literature was performed to identify patients who appeared to have primary colorectal cancer during pregnancy. Thirty-six patients with colon cancer (75.0%), 10 (20.8%) with rectal cancer, and two (4.2%) of unknown sites have been reported in Japanese series. The average age of the mother was 32.2 years. The calculated incidence of colorectal cancer among Japanese pregnant women was one case per 502,316 live births during the years between 1986 through 1995. Although the majority of colorectal cancers diagnosed during pregnancy are rectal carcinomas, the patients in Japan were predominantly complicated by colon cancer. The fetal risk seems small, because there were no cases of colorectal cancer metastatic to the products of conception.

Complete amino acid deprivation in mammalian cells causes a significant enhancement in gene expression for a number of important cellular activities; among these is asparagine synthetase (AS). The data presented demonstrate that, in both nonleukemic (rat Fao hepatoma cells) and human leukemia cells (MOLT-4, NALL-1, and BALL-1), AS mRNA levels, protein content, and enzymatic activity are induced after incubation in an otherwise complete tissue culture medium that is deficient in a single amino acid or in medium that has been depleted of the amino acid asparagine by the addition of asparaginase. Complete amino acid deprivation results in a concerted increase in AS mRNA, protein, and enzymatic activity, which, in conjunction with previously published research, suggests that the mechanism of this cellular response involves transcriptional control of the AS gene. Asparaginase treatment is a standard component of acute lymphoblastic leukemia therapy for which the effectiveness is related to the inability of these cells to upregulate AS activity to a sufficient level. With regard to the asparaginase sensitivity of the three human leukemia cell lines, there was a trend toward an inverse relation to the degree of AS expression. Selection for asparaginase-resistant MOLT-4 sublines resulted in enhanced AS mRNA and protein content regardless of whether the cells had been selected by asparaginase treatment directly or asparagine was removed from the culture medium. Collectively, the data illustrate that further advances in asparaginase therapy will require additional knowledge of amino acid-dependent regulation of AS gene expression and, conversely, that asparaginase resistance represents a model system for investigating metabolite control in a clinically relevant setting.

A 16-year-old girl with refractory acute lymphoblastic leukemia underwent reduced-intensity hematopoietic stem cell transplantation from her two-locus-mismatched haploidentical mother, who was microchimeric for the patient's hematopoietic cells. The conditioning regimen comprised melphalan, fludarabine, and low-dose total body irradiation. Non-T-cell-depleted peripheral blood stem cells were infused with graft-versus-host disease (GVHD) prophylaxis consisting of tacrolimus, prednisolone, and short-course methotrexate. Complete donor-type engraftment without evidence of residual leukemia was confirmed on day 22. Severe GVHD was not observed despite rapid cessation of immunosuppression. The patient remains well in continuous remission 15 months after transplant. This successful experience suggests that maternal hematopoietic stem cell transplants for children, in the presence of microchimerism, may be associated with hyporesponsiveness to the inherited paternal HLA antigens (IPA); preventing severe GVHD.

Chronic granulomatous disease (CGD) is caused by defects of NADPH oxidase. The diagnosis of CGD can be made by analysis of NADPH oxidase activity, however, identification of the CGD subgroups is required before performing mutation analysis. The membrane-bound subunits, gp91phox and p22phox, can be quickly analyzed by flow cytometry, unlike the cytosolic components, p47phox and p67phox. We evaluated the feasibility of flow cytometric detection of p47phox and p67phox with specific monoclonal antibodies in two patients with p47phox deficiency and 7 patients with p67phox deficiency. Consistent with previous observations, p47phox and p67phox were expressed in phagocytes and B cells, but not in T or natural killer cells, from normal controls. In contrast, patients with p47phox and p67phox deficiency showed markedly reduced levels of p47phox and p67phox, respectively. These techniques will be useful to rapidly assess the expression of the cytosolic components, p47phox and p67phox, and represents important secondary screening tests for CGD. © 2013 Springer Science+Business Media New York.

Peripheral blood stem cells (PBSC) may be used as an alternative to bone marrow (BM) for allogeneic transplantation. Since peripheral blood stem cell bank from unrelated volunteer donor has been started in Japan, use of PBSC allografts may be increased. Therefore we surveyed the outcomes of Japanese leukemia children after PBSC and BM transplantation.This retrospective study compared the outcomes of 661 children (0-18 years) with acute lymphoblastic leukaemia (ALL) or acute myeloid leukaemia (AML) who received their first allogeneic peripheral blood stem cell transplantation (PBSCT; n = 90) or bone marrow transplantation (BMT; n = 571) from HLA-matched siblings between January 1996 and December 2007.Neutrophil recovery was faster after PBSCT than after BMT (ALL: P0.0001; AML: P = 0.0002), as was platelet recovery (ALL: P = 0.0008; AML: P = 0.0848). However, the cumulative incidence of chronic graft-versus-host disease (GvHD) was higher after PBSCT than after BMT (ALL: 26.0% vs. 9.9%, P = 0.0066; AML: 41.6% vs. 11.1%, P0.0001). The 5-year disease-free survival (DFS) was lower after PBSCT than after BMT for ALL (40.6% vs. 57.1%, P = 0.0257). The 5-year overall survival (OS) was lower after PBSCT than after BMT for ALL (42.4% vs. 63.7%, P = 0.0032) and AML (49.8% vs. 71.8%, P = 0.0163). Multivariate analysis revealed the use of PBSC was a significant risk factor for DFS and OS. PBSCT and BMT did not differ in relapse rate, acute GvHD for ALL and AML, or in DFS for AML.PBSC allografts in Japanese children engraft faster but are associated with poorer survival and increased chronic GvHD.

A 66-year-old Japanese woman was referred to us because of severe anemia and fever and presented at our hospital. She was eventually diagnosed as having acute myeloblastic leukemia (AML; M0) with non-Hodgkin lymphoma (NHL). We investigated the therapeutic efficacy of L-asparaginase (L-Asp), vincristine and prednisolone for both her AML and NHL. Asparagine synthetase (AS) activity in her AML blast cells was undetectable. A lymph node biopsy specimen revealed NHL of the marginal zone B cell type. Complete remission (CR) of AML and NHL was achieved. CR of the AML lasted for 18 months without further consolidation therapy. We conclude that L-Asp can be an effective drug for the treatment of AML in which blasts are negative for AS.

A transient abnormal myelopoiesis was observed in a newborn with Down syndrome. Cytogenetic study revealed multiple oligoclonal abnormalities: 47,XY,inv(6)(p23q21),+21c[3]/47,XY,der(7)t(1;7)(q25;p15),+21c[1]/47,XY,del(13)(q?),+21c[1]/47,XY,+21c[15]. Ten months after the patient achieved remission, the transient abnormal myelopoiesis evolved to an acute megakaryoblastic leukemia. Cytogenetic study revealed only a single clonal abnormality, 47,XY,der(7)t(1;7)(q25;p15),+21c, identical to one of the structural changes seen at birth. Sequence analysis of the GATA1 gene revealed a deletion–insertion mutation within the exon 2 introducing a stop codon after Arg 64. It may be that the der(7)t(1;7)(q25;p15) abnormality played some selective role in the development of acute megakaryoblastic leukemia in this patient. To our knowledge, the present case is unique in demonstrating a subclone with der(7)t(1;7)(q25;p15) evolving to acute leukemia.

We compared the ability of human leukemia cell lines of various origins to grow in glutamine-deficient media. The growth of B lymphoblastoid cell lines, including promyelocytic HL-60, is highly dependent on glutamine, whereas T-cell lines are able to proliferate in glutamine-free media. Such glutamine dependency has a good inverse correlation with the activity of glutamine synthetase. Moreover, glutamine synthetase can be induced in glutamine-deficient media, especially in glutamine-independent cells. In HL-60 cells, glutamine deprivation results in the decrease of both ATP and dATP levels. The addition of adenine to the culture medium abolishes these changes without restoring cell growth, indicating that the effects of glutamine deprivation on cell growth cannot be fully explained by the perturbation of adenine nucleotide pools.

Treatment of human non-lymphoid cell lines, HL-60 and U937, with etoposide stimulated poly (ADP-ribose) synthesis three- to fourfold, whereas no significant effects were observed in the lymphoid cell lines, Molt4 and CEM. This was confirmed by either an increased uptake of radio-labelled NAD into the acid-insoluble fraction or a fall in cellular NAD levels, which was counteracted by 3-aminobenzamide, an inhibitor of poly(ADP-ribose) polymerase. On the other hand, another DNA damaging agent, N-methyl-N'-nitro-N-nitrosoguanidine augmented poly(ADP-ribose) synthesis equally in both cell types. These results taken together indicate that the activation of poly(ADP-ribose) synthesis following exposure to etoposide is a cell type specific phenomenon.

Down syndrome (DS) patients are frequently complicated with infections, autoimmune phenomena and hematological disorders, including transient abnormal myelopoiesis (TAM) in infancy and acute megakaryoblastic leukaemia (AMKL) in later life. In this study, serum levels of cytokines from 23 TAM and 15 AMKL patients were examined using the highly sensitive microsphere fluorescence system. Statistical differences between DS neonates with or without TAM were found in IL-1beta [median 7.0 pg/ml (0.34-271.6) verses 0.05 pg/ml (0.0-2.4), p=0.034], TNF-alpha [8.11 pg/ml (0.1-253.0) verses 0.41 pg/ml (0.1-1.5), p=0.041], and IFN-gamma [20.0 pg/ml (0.14-406.3) verses 1.5 pg/ml (0.14-5.79), p=0.036]. Moreover, abnormal inflammatory cytokinemia was also found in myelodysplastic syndrome (MDS) and AMKL with DS. These abnormal cytokinemia may have a role in the pathophysiology of TAM, MDS and AMKL in DS, especially in liver fibrosis or myelofibrosis.

A 48-year-old man was referred to Sakai Municipal Hospital with nasal discharge and right facial swelling. The pathological findings of a nasal cavity tumor revealed stage IIB NK/T-cell lymphoma. He was admitted to our hospital and received CHOP therapy, resulting in progressive disease. Irradiation therapy combined with DeVIC chemotherapy also could not shrink his lymphoma. Then, two courses of L-asparaginase(L-Asp) were administered, resulting in partial improvement of the nasal and pharynx lesions, resolution of the fever and improvement of his performance status. On the day before a third course of L-Asp, he again developed a lowgrade fever. Although L-Asp was administered for several days, marked elevation of serum LDH, AST, ALT level, and thrombocytopenia persisted, and he died. Post-mortem examinations revealed hemophagocytosis in the bone marrow and liver, and infiltration of lymphoma cells into multiple organs including left lower lung, liver, spleen and kidneys. Although L-Asp was effective against nasal NK/T-cell lymphoma resistant to combination chemotherapy and irradiation therapy, the effectiveness of the single agent with L-Asp was only transient. L-Asp based regimen should be used as first-line therapy if asparagine synthetase protein expression is low using an immunohistochemical method.

This report concerns two siblings from a tetrad, both of whom had West syndrome with atypical findings on positron emission tomography using [ 18 F] fluorodeoxyglucose. One manifested periventricular leukoencephalopathy, and the other had periventricular leukoencephalopathy as well as porencephaly because of fetal distress and brain parenchymal hemorrhage in the neonatal period. They developed West syndrome at the age of 9 months. Fluorodeoxyglucose–positron emission tomography study performed after cessation of their seizures revealed an increase in glucose metabolism. The corresponding region presented low-level accumulation in [ 11 C]flumazenil positron emission tomography. The patients remained seizure-free for more than 1 month, and their electroencephalograms only occasionally disclosed sporadic paroxysmal discharges. Because of the decreased density of benzodiazepine receptor in these lesions, the activity of the excitatory neuron system may overexpress that of the inhibitory neuron system, thus resulting in epileptogenesis of the lesions. It is suggested that fluorodeoxyglucose and flumazenil–positron emission tomography revealed functional abnormalities and that epileptogenesis of these patients is still active even when the patient is seizure-free and there are mild epileptogenic discharges on electroencephalogram.

Blastic NK cell lymphoma/leukemia is a rare and highly malignant neoplasia in both adults and children. It is characterized by lymphoblastoid morphology without cytoplasmic granules and immature NK cell immunophenotypes (CD56þ, CD57� , CD16� ). It has predilection for extranodal organ involvement, and the prognosis of affected patients is extremely poor under the current chemotherapy. We present a 14-year-old girl who was diagnosed as having blastic NK cell leukemia with mediastinal, pleural, and pericardial involvement. Immunophenotyping of her leukemic cells showed positive for CD2, CD5, CD7, CD34, CD56, HLA-DR, and cytoplasmic CD3. T cell receptor (TCR) and Immunoglobulin heavy chain genes were not rearranged. She received chemotherapy for acute lymphoblastic leukemia incorporating L-asparaginase (L-asp) which successfully induced complete remission. Bone marrow transplantation (BMT) from her HLA-identical sibling was conducted after two courses of consolidation therapy. Expression of aspargine synthetase (AS) protein in the leukemic cells at diagnosis was examined by an immunocytochemical method. She remains in hematological remission for over 36 months after BMT. The expression of AS protein was negative, suggesting that the leukemic cells were sensitive to L-asp. Induction and consolidation therapy incorporating L-asp followed by allo-BMT might be a promising treatment for childhood blastic NK cell leukemia, but more samples of the rare leukemia need to be studied before any definitive conclusions can be drawn. Pediatr Blood Cancer 2004;42:631‐634. 2004 Wiley-Liss, Inc.

We describe a patient with natural killer (NK)/T cell lymphoma who relapsed after autologous peripheral blood stem cell transplantation (auto-PBSCT) and was successfully treated with Escherichia coli (E. coli) and Erwinia L-asparaginase. A 38-year-old male patient with ulcerated tumor at the left thigh was diagnosed as having nasal type NK/T cell lymphoma on the basis of histopathological and flowcytometric findings of tumor, revealing diffuse infiltration of atypical lymphoid cells into blood vessels and expression of CD7 and CD56 antigens, but not CD3. He had tumor infiltration in the bone marrow and at the right lower lung field. After five cycles of CHOP (cyclophosphamide, doxorubicin, vincristine and prednisolone) therapy, the patient achieved complete remission and received high-dose chemotherapy with auto-PBSCT, although the tumor recurred in the right leg 10 months later. Despite salvage chemotherapy, followed by local irradiation and surgical amputation, a tumor recurred at the left upper gingiva 10 days after. Using E. coli L-asparaginase (6000 U/m2/day), the tumor regressed, fever was alleviated and the serum lactate dehydrogenase decreased to normal range after several days. The asparagine synthetase expression in tumor cells was immunohistochemically negative on paraffin-embedded tissues. Because of the anaphylactoid reaction developing after E. coli L-asparaginase, alternative Erwinia L-asparaginase (6000 U/m2/day) was administered, resulting in regression of tumor and fever lysis. L-asparaginase is a promising agent for the treatment of NK/T cell lymphoma.

Barth syndrome (BTHS) is a rare X-linked disorder characterized by cardiomyopathy, short stature, neutropenia, and 3-methylglutaconic aciduria. Mutations have been identified in the TAZ ( G4.5) gene in patients with BTHS. This article presents a mutation analysis of this gene in a Japanese boy with cardiomyopathy with abnormal mitochondria, cyclic neutropenia, and 3-methylglutaconic aciduria (type 2). The analysis revealed a novel missense mutation (R94S) caused by a single nucleotide substitution (C-to-A) in this patient.

Modern clinical treatments of childhood acute lymphoblastic leukemia (ALL) employ enzyme-based methods for depletion of blood asparagine in combination with standard chemotherapeutic agents. L-asparaginase (L-asp) therapy causes depletion of plasma asparagine followed by the loss of intracellular asparagine. Due to the lack of a rapid up-regulation of asparagine synthetase (ASNS) protein content in ALL cells, they are preferentially killed by L-asp. Elevated expression of ASNS within the leukemia cells causes decreased sensitivity to L-asp. The proof of ASNS deficiency in leukemia cells is considered to predictive for effectiveness of L-asp even in acute myeloid leukemia (AML) other than ALL patients. The establishment of quantitative estimation of ASNS protein content would be useful for the L-asp treatment in leukemia therapy. Objective: Our aim was to set up a flow cytometry system to check ASNS deficiency in leukemia cells and to investigate the sensitivity to L-Asp and the ASNS expression in AML leukemia cells. Methods: AML (KG-1, HL-60, U937) and ALL (MOLT-4, RS4;11) and CML (K562) cell lines were grown in RPMI1640 medium with 10% FCS. Primary leukemic cells from the peripheral blood or bone marrow of 20 AML patients were harvested on EDTA and isolated by Ficoll density gradient within 72h. ASNS expression was evaluated by cytosolic flow cytometry with Z5808 McAb (Hybridoma 31: 325-332.2012) and expressed as a ΔMFI(Difference of Mean Fluorescence Intensity(MFI) between by Z5808 and isotypic control) or MFI ratio(MFI by Z5808/MFI by isotypic control). When a sufficient amount of leukemic cells was available, sensitivity to L-asp (expressed as an IC50 - concentration inhibiting 50% of cell viability) was evaluated in vitro by incubating various concentrations of E. coliL-asp with the cells and by measuring the cell viability with a counting kit (WST1 viability assay) at day 3. Results: Determination of IC50 for the HL-60 (⊿MFI 48 ± 8.01, MFI ratio 1.77 ± 0.03) and U937 (⊿MFI 16.7 ± 0.47, MFI ratio 1.19 ± 0.02) demonstrated that these cells were equally sensitive to L-asp than the ALL cell line MOLT-4 in vitro (0.37 and 0.02IU/mL versus 0.15 IU/mL, respectively). K562 and KG-1 (⊿MFI 135.7 ± 5.66, MFI ratio 2.48 ± 0.09) cells with the highest ASNS expression exhibited resistance to L-asp (>10 IU/ml). Both of ASNS Expression by ⊿MFI and MFI ratio was inversely correlated with L-asp sensitivity judging from cell line studies. Judging from cell line study, the threshold for ASNS protein expression effective for L-asp treatment was considered to be 10 IU/mL) Remaining 5 patients were a moderate sensitivity (IC50 < 0.5 IU/mL). ASNS Expression in ALL was almost near zero. ASNS expression in fresh AML was low in all cases except for one M2 and one M4 cases. Indeed, at high ASNS expression, these cases were resistant in vitro to L-asp. The patients with blasts sensitive to L-asp had mainly M1, M5 or M7 AML. A good inverse correlation between ASNS expression and sensitivity to L-asp was observed also in primary leukemic cells from AML patients. Conclusions: We demonstrated here that some of AML cell lines with low ASNS expression are more sensitive to L-asp than leukemia cells with high ASNS expression. Also, fresh AML cells with low ASNS expression are more sensitive to L-asp than with high ASNS expression. 11/13AML or two AMLL cases were supposed to be effective for L-asp. Plasma asparagine depletion by L-asp in selected patients having low ASNS may be a promising therapeutic approach even for AML. This work was supported by Japan Society for the Promotion of Science Grant-in-Aid for Scientific Research (C) KAKENHI Grant Number 24590713. Disclosures No relevant conflicts of interest to declare.

We report a 3-year-old girl with hemophagocytic lymphohistiocytosis (HLH) who received BMT from an HLA-identical unrelated donor when the disease was active. She had entered remission in response to chemotherapy consisting of etoposide and methylprednisolone. After a relapse, her disease became refractory to chemotherapy, and splenectomy was performed with marginal improvement. She underwent BMT from an HLA-identical unrelated donor, conditioned with CY, TBI and anti-thymocyte globulin (ATG). She has been in complete remission for 18 months since the BMT. This result suggests that BMT from an HLA-identical unrelated donor should be considered for HLH even if the disease is active.

Co-incubation of human leukemia cell lines with naturally occurring nucleobases (hypoxanthine or adenine) significantly prevented the cytotoxic activity of 6-thiopurines. Extracellular hypoxanthine decreased the transport of 6-mercaptopurine into cells, but adenine had no significant effect. However, intracellular thioinosine monophosphate accumulation in the presence of 10 μM, 6-mercaptopurine was reduced to below 1% or 10% of that of the controls when 50 μM hypoxanthine or adenine was added, respectively. Finally, in adenine phosphoribosyl transferase deficient mutants, adenine provided no protective effect against 6-thiopurines, whereas hypoxanthine retained its modulating activity. These data suggest that the nucleobases compete with 6-thiopurines for the ribose-phosphate donor, 5′-phosphoribosyl-l-pyrophosphate, thus preventing the formation of active metabolites of 6-thiopurines.

Exposure of human promyelocytic leukemia cell line (HL-60) to VP-16 resulted in accumulation of DNA strand breaks. Concomitantly, intracellular NAD levels fell at 1 h, followed by declines in ATP at 2 h and in GTP, CTP, and UTP at 3 h. Furthermore, marked morphological changes, such as loss of microvilli or bleb formation, appeared at 4 h and cell death by 8–10 h. The addition of an inhibitor of poly(ADP-ribose) polymerase, 3-aminobenzamide (5 m M ), theophylline (2 m M ), or thymidine (1 m M ), prevented these sequential reductions of nucleotide pools and cell death. In fact, the activation of poly(ADP-ribose) synthesis was detectable within a few hours after treatment with VP-16, although it was smaller than that induced by N -methyl- N′ -nitro- N -nitrosoguanidine. These results may suggest the possible role of activation of poly(ADP-ribosyl)ation in VP-16-induced nucleotide pool changes and subsequent interphase death.