The toxicity of very prolonged courses of PEGasparaginase or Erwinia asparaginase in relation to asparaginase activity, with a special focus on dyslipidemia

NARCIS (Netherlands)

Tong, Wing H.; Pieters, Rob; de Groot-Kruseman, Hester A.; Hop, Wim C. J.; Boos, Joachim; Tissing, Wim J. E.; van der Sluis, Inge M.

2014-01-01

We prospectively studied the incidence and clinical course of hypertriglyceridemia and hypercholesterolemia during very prolonged use of asparaginase in relation to levels of asparaginase activity in children with acute lymphoblastic leukemia. We also evaluated the incidence of pancreatitis,

Purification and characterization of camel liver L-asparaginase ...

African Journals Online (AJOL)

L-asparaginase from camel liver was isolated and purified by heat denaturation followed by QAE-Sephadex A-50 column chromatography and SP-Sepharose column chromatography. The purified camel liver L-asparaginase had a molecular weight of 180 kDa (consistent with a homotetramer) and a pI value of 8.6.

Asparaginase-Associated toxicity in children with acute lymphoblastic leukemia

NARCIS (Netherlands)

N. Hijiya (Nobuko); I.M. van der Sluis (Inge)

2016-01-01

textabstractAsparaginase is an integral component of multiagent chemotherapy regimens for the treatment of children with acute lymphoblastic leukemia. Positive outcomes are seen in patients who are able to complete their entire prescribed course of asparaginase therapy. Toxicities associated with

Cloning and molecular analysis of L-asparaginase II gene (ansB

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ZEINAT K. MOHAMED

2015-12-01

Full Text Available The deamination of L-asparagine to L-aspartic acid and ammonia is catalyzed by L-asparaginases (L-asparagine amino hydrolase. The enzyme L-asparaginase is widely distributed in nature from different living organisms, starting from bacteria till mammals and plants. It has been recently thought to be a therapeutic agent in treatment of various lymphoblastic leukemia diseases. There have been many attempts to isolate microorganisms that produce L-asparaginase. L-ASNase producing bacteria, Escherichia coli MG27, was previously isolated from the River Nile and identified. In this study, ansB gene, encoding L-ASNase II from E. coli MG27, was amplified by PCR, cloned and characterized by DNA sequencing. The DNA sequence was then analyzed using bioinformatics analysis and translated into amino acid sequence. Identification of highly conserved amino acid sequence motifs was conducted by comparison against the InterPro database. Analysis revealed that the protein sequence had a catalytic domain of L-asparaginase type II (IPR004550 that belong to asparaginase/glutaminase family (IPR006034 and has asparaginase/glutaminase conserved site (IPR020827. According to results predicted using PSIpred tool, ansB consists of eight α-helices and 13 β-strands.

Solid-State Fermentation vs Submerged Fermentation for the Production of l-Asparaginase.

Science.gov (United States)

Doriya, K; Jose, N; Gowda, M; Kumar, D S

l-Asparaginase, an enzyme that catalyzes l-asparagine into aspartic acid and ammonia, has relevant applications in the pharmaceutical and food industry. So, this enzyme is used in the treatment of acute lymphoblastic leukemia, a malignant disorder in children. This enzyme is also able to reduce the amount of acrylamide found in carbohydrate-rich fried and baked foods which is carcinogenic to humans. The concentration of acrylamide in food can be reduced by deamination of asparagine using l-Asparaginase. l-Asparaginase is present in plants, animals, and microbes. Various microorganisms such as bacteria, yeast, and fungi are generally used for the production of l-Asparaginase as it is difficult to obtain the same from plants and animals. l-Asparaginase from bacteria causes anaphylaxis and other abnormal sensitive reactions. To overcome this, eukaryotic organisms such as fungi can be used for the production of l-Asparaginase. l-Asparaginase can be produced either by solid-state fermentation (SSF) or by submerged fermentation (SmF). SSF is preferred over SmF as it is cost effective, eco-friendly and it delivers high yield of enzyme. SSF process utilizes agricultural and industrial wastes as solid substrate. The contamination level is substantially reduced in SSF through low moisture content. Current chapter will discuss in detail the chemistry and applications of l-Asparaginase enzyme and various methods available for the production of the enzyme, especially focusing on the advantages and limitations of SSF and SmF processes. © 2016 Elsevier Inc. All rights reserved.

Distinct physiological roles for the two L-asparaginase isozymes of Escherichia coli

Energy Technology Data Exchange (ETDEWEB)

Srikhanta, Yogitha N. [Department of Microbiology and Immunology, The University of Melbourne, Victoria 3010 (Australia); Atack, John M.; Beacham, Ifor R. [Institute for Glycomics, Griffith University, Gold Coast, QLD 4222 (Australia); Jennings, Michael P., E-mail: m.jennings@griffith.edu.au [Institute for Glycomics, Griffith University, Gold Coast, QLD 4222 (Australia)

2013-07-05

Highlights: •Escherichia coli contains two L-asparaginase isozymes with distinct localization, kinetics and regulation. •Mutant strains were used to examine the roles of these enzymes in L-asparagine utilization. •We report that L-asparaginase II permits growth on asparagine and glycerol under anaerobic conditions. •We propose that this enzyme is the first step in a co-regulated pathway leading to fumarate. •The pathway is regulated by anaerobiosis and cAMP and provides a terminal elector acceptor. -- Abstract: Escherichia coli expresses two L-asparaginase (EC 3.5.1.1) isozymes: L-asparaginse I, which is a low affinity, cytoplasmic enzyme that is expressed constitutively, and L-asparaginase II, a high affinity periplasmic enzyme that is under complex co-transcriptional regulation by both Fnr and Crp. The distinct localisation and regulation of these enzymes suggest different roles. To define these roles, a set of isogenic mutants was constructed that lacked either or both enzymes. Evidence is provided that L-asparaginase II, in contrast to L-asparaginase I, can be used in the provision of an anaerobic electron acceptor when using a non-fermentable carbon source in the presence of excess nitrogen.

Autophagy suppression potentiates the anti-glioblastoma effect of asparaginase in vitro and in vivo

Science.gov (United States)

Chen, Qicheng; Ye, Li; Fan, Jiajun; Zhang, Xuyao; Wang, Huan; Liao, Siyang; Song, Ping; Wang, Ziyu; Wang, Shaofei; Li, Yubin; Luan, Jingyun; Wang, Yichen; Chen, Wei; Zai, Wenjing; Yang, Ping; Cao, Zhonglian; Ju, Dianwen

2017-01-01

Asparaginase has been reported to be effective in the treatment of various leukemia and several malignant solid cancers. However, the anti-tumor effect of asparaginase is always restricted due to complicated mechanisms. Herein, we investigated the mechanisms of how glioblastoma resisted asparaginase treatment and reported a novel approach to enhance the anti-glioblastoma effect of asparaginase. We found that asparaginase could induce growth inhibition and caspase-dependent apoptosis in U87MG/U251MG glioblastoma cells. Meanwhile, autophagy was activated as indicated by autophagosomes formation and upregulated expression of LC3-II. Importantly, abolishing autophagy using chloroquine (CQ) and LY294002 enhanced the cytotoxicity and apoptosis induced by asparaginase in U87MG/U251MG cells. Further study proved that Akt/mTOR and Erk signaling pathways participated in autophagy induction, while reactive oxygen species (ROS) served as an intracellular regulator for both cytotoxicity and autophagy in asparaginase-treated U87MG/U251MG cells. Moreover, combination treatment with autophagy inhibitor CQ significantly enhanced anti-glioblastoma efficacy of asparaginase in U87MG cell xenograft model. Taken together, our results demonstrated that inhibition of autophagy potentiated the anti-tumor effect of asparagine depletion on glioblastoma, indicating that targeting autophagy and asparagine could be a potential approach for glioblastoma treatment. PMID:29207624

Cerebrospinal fluid asparagine depletion during pegylated asparaginase therapy in children with acute lymphoblastic leukaemia

DEFF Research Database (Denmark)

Henriksen, Louise Tram; Nersting, Jacob; Raja, Raheel A

2014-01-01

L-asparaginase is an important drug in the treatment of childhood acute lymphoblastic leukaemia (ALL). Cerebrospinal fluid (CSF) asparagine depletion is considered a marker of asparaginase effect in the central nervous system (CNS) and may play a role in CNS-directed anti-leukaemia therapy. The o...... in CSF asparagine corresponded to serum enzyme activities above 50 iu/l. Higher serum enzyme activities were not followed by more extensive depletion. In conclusion, pegylated asparaginase 1000 iu/m(2) i.m. every second week effectively reduced CSF asparagine levels.......L-asparaginase is an important drug in the treatment of childhood acute lymphoblastic leukaemia (ALL). Cerebrospinal fluid (CSF) asparagine depletion is considered a marker of asparaginase effect in the central nervous system (CNS) and may play a role in CNS-directed anti-leukaemia therapy....... The objective of this study was to describe CSF asparagine depletion during 30 weeks of pegylated asparaginase therapy, 1000 iu/m(2) i.m. every second week, and to correlate CSF asparagine concentration with serum L-asparaginase enzyme activity. Danish children (1-17 years) with ALL, treated according...

Recombinant L-Asparaginase from Zymomonas mobilis: A Potential New Antileukemic Agent Produced in Escherichia coli.

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Karen Einsfeldt

Full Text Available L-asparaginase is an enzyme used as a chemotherapeutic agent, mainly for treating acute lymphoblastic leukemia. In this study, the gene of L-asparaginase from Zymomonas mobilis was cloned in pET vectors, fused to a histidine tag, and had its codons optimized. The L-asparaginase was expressed extracellularly and intracellularly (cytoplasmically in Escherichia coli in far larger quantities than obtained from the microorganism of origin, and sufficient for initial cytotoxicity tests on leukemic cells. The in silico analysis of the protein from Z. mobilis indicated the presence of a signal peptide in the sequence, as well as high identity to other sequences of L-asparaginases with antileukemic activity. The protein was expressed in a bioreactor with a complex culture medium, yielding 0.13 IU/mL extracellular L-asparaginase and 3.6 IU/mL intracellular L-asparaginase after 4 h of induction with IPTG. The cytotoxicity results suggest that recombinant L-asparaginase from Z. mobilis expressed extracellularly in E.coli has a cytotoxic and cytostatic effect on leukemic cells.

Isolation and Identification of L-asparaginase producing Erwinia strains which isolated from Potato Farms

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Arastoo Badoei-Dalfard

2016-09-01

Full Text Available Introduction: L-Asparaginase can be effectively used for the treatment of lymphoblastic leukemia. The rapid growth of cancer cells are needed for L-asparagine abundant storage. L-asparaginase catalyzes the hydrolysis of L-asparagine into L-aspartic acid and ammonia. The purpose of this study was to isolate and identify the L-asparaginase producing Erwinia strains from the potato farms of Jiroft. Materials and methods: Pectolytic Erwinia species isolated from crumbling potato in M9 medium. The desired L-asparaginase producing bacteria were isolated based on the color changes. Biochemical-microbial and the plant pathogenicity tests of these strains were also investigated with potato and geranium. The L-asparaginase production and molecular detection of these Erwinia strains were also investigated. Results: In this study, L-asparaginase producing Erwinia was isolated on the CVP and M9 mediums. The inoculation of Erwinia strains on the potato and geranium plants showed that Er8 and Er11 species have the ability to cause plant pathogenicity. Results showed that the maximum pathogenicity of Er8 and Er11 was observed after 48 and 15 h of inoculation in potato and geranium plants, respectively. 16S rDNA sequencing and phylogenetic analyses exhibited that Er8 and Er11 strains were similar to Erwinia chrysanthemi with 98% homology. Discussion and conclusion: Because of several applications of the Erwinia L-asparaginase in various fields, isolated Erwinia and their L-asparaginase can be suitable for applied utilization.

Cell-cycle inhibition by Helicobacter pylori L-asparaginase.

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Claudia Scotti

Full Text Available Helicobacter pylori (H. pylori is a major human pathogen causing chronic gastritis, peptic ulcer, gastric cancer, and mucosa-associated lymphoid tissue lymphoma. One of the mechanisms whereby it induces damage depends on its interference with proliferation of host tissues. We here describe the discovery of a novel bacterial factor able to inhibit the cell-cycle of exposed cells, both of gastric and non-gastric origin. An integrated approach was adopted to isolate and characterise the molecule from the bacterial culture filtrate produced in a protein-free medium: size-exclusion chromatography, non-reducing gel electrophoresis, mass spectrometry, mutant analysis, recombinant protein expression and enzymatic assays. L-asparaginase was identified as the factor responsible for cell-cycle inhibition of fibroblasts and gastric cell lines. Its effect on cell-cycle was confirmed by inhibitors, a knockout strain and the action of recombinant L-asparaginase on cell lines. Interference with cell-cycle in vitro depended on cell genotype and was related to the expression levels of the concurrent enzyme asparagine synthetase. Bacterial subcellular distribution of L-asparaginase was also analysed along with its immunogenicity. H. pylori L-asparaginase is a novel antigen that functions as a cell-cycle inhibitor of fibroblasts and gastric cell lines. We give evidence supporting a role in the pathogenesis of H. pylori-related diseases and discuss its potential diagnostic application.

Asparaginase-associated pancreatitis in childhood acute lymphoblastic leukaemia: an observational Ponte di Legno Toxicity Working Group study.

Science.gov (United States)

Wolthers, Benjamin O; Frandsen, Thomas L; Baruchel, André; Attarbaschi, Andishe; Barzilai, Shlomit; Colombini, Antonella; Escherich, Gabriele; Grell, Kathrine; Inaba, Hiroto; Kovacs, Gábor; Liang, Der-Cherng; Mateos, Marion; Mondelaers, Veerle; Möricke, Anja; Ociepa, Tomasz; Samarasinghe, Sujith; Silverman, Lewis B; van der Sluis, Inge M; Stanulla, Martin; Vrooman, Lynda M; Yano, Michihiro; Zapotocka, Ester; Schmiegelow, Kjeld

2017-09-01

Survival for childhood acute lymphoblastic leukaemia surpasses 90% with contemporary therapy; however, patients remain burdened by the severe toxic effects of treatment, including asparaginase-associated pancreatitis. To investigate the risk of complications and risk of re-exposing patients with asparaginase-associated pancreatitis to asparaginase, 18 acute lymphoblastic leukaemia trial groups merged data for this observational study. Patient files from 26 trials run by 18 trial groups were reviewed on children (aged 1·0-17·9 years) diagnosed with t(9;22)-negative acute lymphoblastic leukaemia between June 1, 1996, and Jan 1, 2016, who within 50 days of asparaginase exposure developed asparaginase-associated pancreatitis. Asparaginase-associated pancreatitis was defined by at least two criteria: abdominal pain, pancreatic enzymes at least three times the upper limit of normal (ULN), and imaging compatible with pancreatitis. Patients without sufficient data for diagnostic criteria were excluded. Primary outcomes were defined as acute and persisting complications of asparaginase-associated pancreatitis and risk of re-exposing patients who suffered an episode of asparaginase-associated pancreatitis to asparaginase. Data were collected from Feb 2, 2015, to June 30, 2016, and analysed and stored in a common database at Rigshospitalet, Copenhagen, Denmark. Of 465 patients with asparaginase-associated pancreatitis, 33 (8%) of 424 with available data needed mechanical ventilation, 109 (26%) of 422 developed pseudocysts, acute insulin therapy was needed in 81 (21%) of 393, and seven (2%) of 458 patients died. Risk of assisted mechanical ventilation, need for insulin, pseudocysts, or death was associated with older age (median age for patients with complications 10·5 years [IQR 6·4-13·8] vs without complications 6·1 years [IQR 3·6-12·2], ppancreatitis, 31 (11%) of 275 patients still needed insulin or had recurrent abdominal pain or both. Both the risk of persisting

CT values of fatty liver due to L-asparaginase administration

Energy Technology Data Exchange (ETDEWEB)

Muraki, Kotaro; Kubo, Kazuaki; Hamamoto, Kazuko; Ueda, Kazuhiro; Kashiwado, Kozo; Ito, Katsuhide (Hiroshima Red Cross Hospital (Japan))

1984-02-01

Chemotherapy involving L-asparaginase was performed on a 9-year-old female child with malignant lymphoma, and a 3-year-old male child and a 14-year-old female child with acute lymphatic leukemia, and the course of L-asparaginase-induced fatty liver was followed up primarily by CT findings. In all 3 cases, L-asparaginase administration caused a marked fatty liver characterized by a diffuse cold area of the liver and a decrease in the value of the liver (liver/spleen<1) on CT. Hypoproteinemia, hypofibrinogenemia and elevations of GOT and GPT were simultaneously observed, but marked anemia, pancreatitis, decreased glucose tolerance and central nervous disorder did not occur. Recovery of fatty liver was slower in CT findings than in blood biochemistry, taking about 4 weeks.

Population pharmacokinetics of intravenous Erwinia asparaginase in pediatric acute lymphoblastic leukemia patients

NARCIS (Netherlands)

Sassen, Sebastiaan D. T.; Mathôt, Ron A. A.; Pieters, Rob; Kloos, Robin Q. H.; de Haas, Valérie; Kaspers, Gertjan J. L.; van den Bos, Cor; Tissing, Wim J. E.; te Loo, Maroeska; Bierings, Marc B.; Kollen, Wouter J. W.; Zwaan, Christian M.; van der Sluis, Inge M.

2017-01-01

Erwinia asparaginase is an important component in the treatment of pediatric acute lymphoblastic leukemia. A large variability in serum concentrations has been observed after intravenous Erwinia asparaginase. Currently, Dutch Childhood Oncology Group protocols dose alterations are based on trough

Population pharmacokinetics of intravenous Erwinia asparaginase in pediatric acute lymphoblastic leukemia patients

NARCIS (Netherlands)

Sassen, Sebastiaan D. T.; Mathot, Ron A. A.; Pieters, Rob; Kloos, Robin Q. H.; de Haas, Valerie; Kaspers, Gertjan J. L.; van den Bos, Cor; Tissing, Wim J. E.; te Loo, D. Maroeska W. M.; Bierings, Marc B.; Kollen, Wouter J. W.; Zwaan, Christian M.; van der Sluis, Inge M.

Erwinia asparaginase is an important component in the treatment of pediatric acute lymphoblastic leukemia. A large variability in serum concentrations has been observed after intravenous Erwinia asparaginase. Currently, Dutch Childhood Oncology Group protocols dose alterations are based on trough

Acrylamide Mitigation in Fried Kochchi Kesel Chips Using Free and Immobilized Fungal Asparaginase

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Baskar Gurunathan

2018-01-01

Full Text Available Acrylamide is formed when food products are fried at high temperature. Food researchers are constantly working on developing efficient methods for mitigating acrylamide in fried foods. In the present study, asparaginase from Aspergillus terreus was used for the pretreatment of kochchi kesel banana slices before frying to mitigate acrylamide formation during frying. The soaking and frying conditions were optimized using free and chitosan-immobilized asparaginase. The optimal soaking temperature and time were found to be 60 °C and 20 min, respectively. The optimal activity of free and chitosan-immobilized asparaginase was found to be 5 U/mL. The optimal frying temperature and time for both free and chitosan-immobilized asparaginase were found to be 180 °C for 25 min with an acrylamide mass fraction of 1866 and 954 µg/kg, respectively. The kinetics and thermodynamics of enzymatic mitigation of acrylamide in kochchi kesel chips were also studied. It was concluded that the chitosan-immobilized asparaginase pretreatment of kochchi kesel slices is an effective method for mitigation of acrylamide.

Asparaginase-associated pancreatitis in children with acute lymphoblastic leukaemia in the NOPHO ALL2008 protocol

DEFF Research Database (Denmark)

Raja, Raheel A; Schmiegelow, Kjeld; Albertsen, BK

2014-01-01

L-asparaginase is an important drug in the treatment of childhood acute lymphoblastic leukaemia (ALL). Treatment is associated with several toxicities, including acute pancreatitis. Clinical course, presentation, re-exposure to L-asparginase after pancreatitis and risk of recurrent pancreatitis...... within an asparaginase-intensive protocol has been poorly reported. Children (1-17 years) on the ongoing Nordic Society of Paediatric Haematology and Oncology (NOPHO) ALL2008 protocol with asparaginase-associated pancreatitis (AAP) diagnosed between 2008 and 2012 were identified through the online NOPHO...... ALL toxicity registry. NOPHO ALL2008 includes eight or 15 doses of intramuscular pegylated L-asparginase (PEG-asparaginase) 1000 iu/m(2) /dose at 2-6 weeks intervals, with a total of 30 weeks of exposure to PEG-asparaginase (clinicaltrials.gov no: NCT00819351). Of 786 children, 45 were diagnosed...

Obesity challenges the hepatoprotective function of the integrated stress response to asparaginase exposure in mice.

Science.gov (United States)

Nikonorova, Inna A; Al-Baghdadi, Rana J T; Mirek, Emily T; Wang, Yongping; Goudie, Michael P; Wetstein, Berish B; Dixon, Joseph L; Hine, Christopher; Mitchell, James R; Adams, Christopher M; Wek, Ronald C; Anthony, Tracy G

2017-04-21

Obesity increases risk for liver toxicity by the anti-leukemic agent asparaginase, but the mechanism is unknown. Asparaginase activates the integrated stress response (ISR) via sensing amino acid depletion by the eukaryotic initiation factor 2 (eIF2) kinase GCN2. The goal of this work was to discern the impact of obesity, alone versus alongside genetic disruption of the ISR, on mechanisms of liver protection during chronic asparaginase exposure in mice. Following diet-induced obesity, biochemical analysis of livers revealed that asparaginase provoked hepatic steatosis that coincided with activation of another eIF2 kinase PKR-like endoplasmic reticulum kinase (PERK), a major ISR transducer to ER stress. Genetic loss of Gcn2 intensified hepatic PERK activation to asparaginase, yet surprisingly, mRNA levels of key ISR gene targets such as Atf5 and Trib3 failed to increase. Instead, mechanistic target of rapamycin complex 1 (mTORC1) signal transduction was unleashed, and this coincided with liver dysfunction reflected by a failure to maintain hydrogen sulfide production or apolipoprotein B100 (ApoB100) expression. In contrast, obese mice lacking hepatic activating transcription factor 4 ( Atf4 ) showed an exaggerated ISR and greater loss of endogenous hydrogen sulfide but normal inhibition of mTORC1 and maintenance of ApoB100 during asparaginase exposure. In both genetic mouse models, expression and phosphorylation of Sestrin2, an ATF4 gene target, was increased by asparaginase, suggesting mTORC1 inhibition during asparaginase exposure is not driven via eIF2-ATF4-Sestrin2. In conclusion, obesity promotes a maladaptive ISR during asparaginase exposure. GCN2 functions to repress mTORC1 activity and maintain ApoB100 protein levels independently of Atf4 expression, whereas hydrogen sulfide production is promoted via GCN2-ATF4 pathway. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

L-Asparaginase from Streptomyces griseus NIOT-VKMA29: optimization of process variables using factorial designs and molecular characterization of L-asparaginase gene

Science.gov (United States)

Meena, Balakrishnan; Anburajan, Lawrance; Sathish, Thadikamala; Vijaya Raghavan, Rangamaran; Dharani, Gopal; Valsalan Vinithkumar, Nambali; Kirubagaran, Ramalingam

2015-07-01

Marine actinobacteria are known to be a rich source for novel metabolites with diverse biological activities. In this study, a potential extracellular L-asparaginase was characterised from the Streptomyces griseus NIOT-VKMA29. Box-Behnken based optimization was used to determine the culture medium components to enhance the L-asparaginase production. pH, starch, yeast extract and L-asparagine has a direct correlation for enzyme production with a maximum yield of 56.78 IU mL-1. A verification experiment was performed to validate the experiment and more than 99% validity was established. L-Asparaginase biosynthesis gene (ansA) from Streptomyces griseus NIOT-VKMA29 was heterologously expressed in Escherichia coli M15 and the enzyme production was increased threefold (123 IU mL-1) over the native strain. The ansA gene sequences reported in this study encloses several base substitutions with that of reported sequences in GenBank, resulting in altered amino acid sequences of the translated protein.

CT values of fatty liver due to L-asparaginase administration

International Nuclear Information System (INIS)

Muraki, Kotaro; Kubo, Kazuaki; Hamamoto, Kazuko; Ueda, Kazuhiro; Kashiwado, Kozo; Ito, Katsuhide

1984-01-01

Chemotherapy involving L-asparaginase was performed on a 9-year-old female child with malignant lymphoma, and a 3-year-old male child and a 14-year-old female child with acute lymphatic leukemia, and the course of L-asparaginase-induced fatty liver was followed up primarily by CT findings. In all 3 cases, L-asparaginase administration caused a marked fatty liver characterized by a diffuse cold area of the liver and a decrease in the value of the liver (liver/spleen<1) on CT. Hypoproteinemia, hypofibrinogenemia and elevations of GOT and GPT were simultaneously observed, but marked anemia, pancreatitis, decreased glucose tolerance and central nervous disorder did not occur. Recovery of fatty liver was slower in CT findings than in blood biochemistry, taking about 4 weeks. (Chiba, N.)

Gene sequencing, cloning, and expression of the recombinant L- Asparaginase of Pseudomonas aeruginosa SN4 strain in Escherichia coli

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Arastoo Badoei-dalfard

2016-03-01

Full Text Available Introduction: L- asparaginase is in an excessive demand in medical applications and in food treating industries, the request for this therapeutic enzyme is growing several folds every year. Materials and methods: In this study, a L- asparaginase gene from Pseudomonas aeruginosa strain SN4 was sequenced and cloned in E. coli. Primers were designed based on L- asparaginase from P. aeruginosa DSM 50071, which show high similarity to SN4 strain, according to 16S rRNA sequence. The L- asparaginase gene was exposed to restriction digestion with NdeI and XhoI enzymes and then ligated into pET21a plasmid. The ligated sample was transformed into competent E. coli (DE3 pLysS DH5a cells, according to CaCl2 method. The transformed E. coli cells were grown into LB agar plate containing 100 µg/ml ampicillin, IPTG (1 mM. Results: Recombinant L- asparaginase from E. coli BL21 induced after 9 h of incubation and showed high L- asparaginase activity about 93.4 IU/ml. Recombinant L- asparaginase sequencing and alignments showed that the presumed amino acid sequence composed of 350 amino acid residues showed high similarity with P. aeruginosa L- asparaginases about 99%. The results also indicated that SN4 L- asparaginase has the catalytic residues and conserve region similar to other L- asparaginases. Discussion and conclusion: This is the first report on cloning and expression of P. aeruginosa L- asparaginases in Escherichia coli. These results indicated a potent source of L- asparaginase for in vitro and in vivio anticancer consideration. 

Cost-analysis of treatment of childhood acute lymphoblastic leukemia with asparaginase preparations: The impact of expensive chemotherapy

NARCIS (Netherlands)

W.H. Tong (Wing); I.M. van der Sluis (Inge); C.J.M. Alleman (Cathelijne); R.R. van Litsenburg (Raphaële ); G.J. Kaspers (Gertjan); R. Pieters (Rob); C.A. Uyl-de Groot (Carin)

2013-01-01

markdownabstract__Abstract__ Asparaginase is an expensive drug, but important in childhood acute lymphoblastic leukemia. In order to compare costs of PEGasparaginase, Erwinia asparaginase and native E. coli asparaginase, we performed a cost-analysis in the Dutch Childhood Oncology Group ALL-10

Crystallization and preliminary crystallographic analysis of l-asparaginase from Erwinia carotovora

International Nuclear Information System (INIS)

Wikman, Linnea E. K.; Krasotkina, Julya; Kuchumova, Anastasia; Sokolov, Nikolay N.; Papageorgiou, Anastassios C.

2005-01-01

Er. carotovoral-asparaginase, a potential antileukaemic agent, has been crystallized. Crystals diffract to 2.6 Å using a rotating-anode source and belong to space group P2 1 , with unit-cell parameters a = 78.0, b = 112.3, c = 78.7 Å, β = 101.9° and a homotetramer in the crystallographic asymmetric unit. Bacterial l-asparaginases have been used as therapeutic agents in the treatment of acute childhood lymphoblastic leukaemia for over 30 y. However, their use is limited owing to the glutaminase activity of the administered enzymes, which results in serious side effects. In contrast, l-asparaginase from Erwinia carotovora exhibits low glutaminase activity at physiological concentrations of l-asparagine and l-glutamine in the blood. Recombinant Er. carotovoral-asparaginase was crystallized in the presence of l-glutamate by the hanging-drop vapour-diffusion method using 10 mg ml −1 purified enzyme, 16–18%(w/v) PEG 3350 and 0.2 M NaF. X-ray diffraction data were collected to 2.6 Å at 293 K using an in-house rotating-anode generator. The crystals belong to the monoclinic P2 1 space group, with unit-cell parameters a = 78.0, b = 112.3, c = 78.7 Å, β = 101.9° and a homotetramer in the crystallographic asymmetric unit. A molecular-replacement solution has been found and refinement is currently in progress. The crystal structure may provide leads towards protein-engineering efforts aimed at safer asparaginase administration in leukaemia treatment

Studies on Optimization of Growth Parameters for L-Asparaginase Production by Streptomyces ginsengisoli

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Neelima Deshpande

2014-01-01

Full Text Available A species of Streptomyces, Streptomyces ginsengisoli, a river isolate, was evaluated for production of an enzyme, L-asparaginase, with multiple functions mainly anticancer activity. The actinomycete was subjected to submerged fermentation by “shake flask” method. The quantity of L-asparaginase produced was estimated as 3.23 μmol/mL/min. The effect of various culture conditions on L-asparaginase production was studied by adopting a method of variation in one factor at a time. Of the various conditions tested, glucose (followed by starch and peptone served as good carbon and nitrogen sources, respectively, for maximal production of enzyme at pH 8. The temperature of 30°C and an incubation period of 5 days with 0.05 g% asparagine concentration were found to be optimum for L-asparaginase production.

Consensus expert recommendations for identification and management of asparaginase hypersensitivity and silent inactivation

NARCIS (Netherlands)

I.M. van der Sluis (Inge); L.M. Vrooman (Lynda M.); R. Pieters (Rob); A. Baruchel (André); G. Escherich (Gabriele); N. Goulden (Nicholas); V. Mondelaers (Veerle); J.S. de Toledo (Jose Sanchez); C. Rizzari (Carmelo); L.B. Silverman (Lewis); J.A. Whitlock (James A.)

2016-01-01

textabstractL-asparaginase is an integral component of therapy for acute lymphoblastic leukemia. However, asparaginase-related complications, including the development of hypersensitivity reactions, can limit its use in individual patients. Of considerable concern in the setting of clinical allergy

Anti-Erwinia asparaginase antibodies during treatment of childhood acute lymphoblastic leukemia and their relationship to outcome

DEFF Research Database (Denmark)

Albertsen, BK; Schmiegelow, Kjeld; Schrøder, Henrik

2002-01-01

PURPOSE: A case-control study was performed to determine whether patients who had been treated with Erwinia asparaginase as part of their treatment for childhood acute lymphoblastic leukemia (ALL) and who showed relapsed of their disease more often developed anti-asparaginase antibodies than...... (median follow-up 70 months). Anti- Erwinia asparaginase antibodies were measured (ELISA method) during maintenance therapy after asparaginase treatment (30,000 IU/m(2) daily for 10 days in all patients plus twice weekly for 2 weeks in intermediate-risk and high-risk ALL patients). RESULTS: The overall...... incidence of anti- Erwinia asparaginase antibodies was 8% (3 of 39 patients). There was no statistically significant difference in the incidence of antibody formation between patients who had suffered relapse (1 of 13) and those who had not (2 of 26). In two of the three patients who developed antibodies...

Crystallization and preliminary crystallographic analysis of l-asparaginase from Erwinia carotovora

Energy Technology Data Exchange (ETDEWEB)

Wikman, Linnea E. K. [Turku Centre for Biotechnology, University of Turku and Åbo Akademi University, Turku 20521 (Finland); Krasotkina, Julya; Kuchumova, Anastasia; Sokolov, Nikolay N. [Institute for Biomedical Chemistry, Russian Academy of Medical Sciences, 559-B, 10 Pogodinskay St, Moscow 119121 (Russian Federation); Papageorgiou, Anastassios C., E-mail: tassos.papageorgiou@btk.fi [Turku Centre for Biotechnology, University of Turku and Åbo Akademi University, Turku 20521 (Finland)

2005-04-01

Er. carotovoral-asparaginase, a potential antileukaemic agent, has been crystallized. Crystals diffract to 2.6 Å using a rotating-anode source and belong to space group P2{sub 1}, with unit-cell parameters a = 78.0, b = 112.3, c = 78.7 Å, β = 101.9° and a homotetramer in the crystallographic asymmetric unit. Bacterial l-asparaginases have been used as therapeutic agents in the treatment of acute childhood lymphoblastic leukaemia for over 30 y. However, their use is limited owing to the glutaminase activity of the administered enzymes, which results in serious side effects. In contrast, l-asparaginase from Erwinia carotovora exhibits low glutaminase activity at physiological concentrations of l-asparagine and l-glutamine in the blood. Recombinant Er. carotovoral-asparaginase was crystallized in the presence of l-glutamate by the hanging-drop vapour-diffusion method using 10 mg ml{sup −1} purified enzyme, 16–18%(w/v) PEG 3350 and 0.2 M NaF. X-ray diffraction data were collected to 2.6 Å at 293 K using an in-house rotating-anode generator. The crystals belong to the monoclinic P2{sub 1} space group, with unit-cell parameters a = 78.0, b = 112.3, c = 78.7 Å, β = 101.9° and a homotetramer in the crystallographic asymmetric unit. A molecular-replacement solution has been found and refinement is currently in progress. The crystal structure may provide leads towards protein-engineering efforts aimed at safer asparaginase administration in leukaemia treatment.

Anaphylactic reaction to polyethylene-glycol conjugated-asparaginase: premedication and desensitization may not be sufficient.

Science.gov (United States)

Sahiner, Umit M; Yavuz, S Tolga; Gökce, Muge; Buyuktiryaki, Betul; Altan, Ilhan; Aytac, Selin; Tuncer, Murat; Tuncer, Ayfer; Sackesen, Cansin

2013-08-01

In hypersensitive reactions to native L-asparaginase, either premedication and desensitization or substitution with polyethylene glycol conjugated asparaginase (PEG-ASP) is preferred. Anaphylaxis with PEG-ASP is rare. An 8-year-old girl and a 2.5-year-old boy, both diagnosed as having acute lymphoblastic leukemia, presented with native L-asparaginase hypersensitivity and substitution with PEG-ASP was preferred. They received a premedication (methylprednisolone, hydroxyzine and ranitidine) followed by desensitization with PEG-ASP infusion. Both patients developed anaphylaxis with peg-asparaginase. These are the first reported cases of anaphylactic reaction to PEG-ASP, despite the application of both premedication and desensitization. Anaphylaxis with PEG-ASP is very rare and premedication and desensitization protocols may not prevent these hypersensitive reactions. © 2013 The Authors. Pediatrics International © 2013 Japan Pediatric Society.

E. coli-Derived L-Asparaginase Retains Enzymatic and Cytotoxic Activity In Vitro for Canine and Feline Lymphoma after Cold Storage

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Jackie M. Wypij

2013-01-01

Full Text Available Background. L-asparaginase is effective in treating canine and feline lymphoma, however chemotherapy poses a significant financial cost to veterinary clients, limiting therapy for many pets. Single dose vials result in significant drug wastage, and drug shortages limit consistent availability for pets. Hypothesis. E. coli-derived asparaginase retains enzymatic and antineoplastic activity in canine and feline lymphoma cells after cold storage. Methods. E. coli-derived asparaginase was cold-stored: refrigeration (7–14 days and freezing (14 days–six months, one to three freeze/thaw cycles. Enzymatic activity of asparaginase was measured via a modified asparagine assay. Effects of cold-stored asparaginase on cell proliferation and cytotoxicity were measured in feline (MYA-1, F1B and canine (17–71, OSW lymphoma cells. Results. Cold-stored E. coli-derived asparaginase retains antineoplastic activity in all four cell lines tested. Cold-stored E. coli-derived L-asparaginase depletes asparagine and retains enzymatic activity. Duration of refrigeration, duration of freezing, and number of freeze-thaw cycles have minimal effect on asparaginase enzyme activity. Conclusions and Clinical Importance. This study establishes a scientific basis for long-term cold storage of reconstituted E. coli-derived asparaginase that may result in better utilization of limited drug resources and improve financial feasibility of E. coli-derived asparaginase as a therapeutic option for pets with lymphoma.

Current applications and different approaches for microbial L-asparaginase production

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Jorge Javier Muso Cachumba

Full Text Available ABSTRACT L-asparaginase (EC 3.5.1.1 is an enzyme that catalysis mainly the asparagine hydrolysis in L-aspartic acid and ammonium. This enzyme is presented in different organisms, such as microorganisms, vegetal, and some animals, including certain rodent's serum, but not unveiled in humans. It can be used as important chemotherapeutic agent for the treatment of a variety of lymphoproliferative disorders and lymphomas (particularly acute lymphoblastic leukemia (ALL and Hodgkin's lymphoma, and has been a pivotal agent in chemotherapy protocols from around 30 years. Also, other important application is in food industry, by using the properties of this enzyme to reduce acrylamide levels in commercial fried foods, maintaining their characteristics (color, flavor, texture, security, etc. Actually, L-asparaginase catalyzes the hydrolysis of L-asparagine, not allowing the reaction of reducing sugars with this aminoacid for the generation of acrylamide. Currently, production of L-asparaginase is mainly based in biotechnological production by using some bacteria. However, industrial production also needs research work aiming to obtain better production yields, as well as novel process by applying different microorganisms to increase the range of applications of the produced enzyme. Within this context, this mini-review presents L-asparaginase applications, production by different microorganisms and some limitations, current investigations, as well as some challenges to be achieved for profitable industrial production.

Withania somnifera (Ashwagandha): a Novel Source of L-asparaginase

Institute of Scientific and Technical Information of China (English)

Vishal P. Oza; Shraddha D.Trivedi; Pritesh P.Parmar; R.B.Subramanian

2009-01-01

Different parts of plant species belonging to Solanaceae and Fabaceae families were screened for L-asparaginase enzyme (E.C.3.5.1.1.). Among 34 plant species screened for L-asparaginase enzyme, Withania somnifera L. Was identified as a potential source of the enzyme on the basis of high specific activity of the enzyme. The enzyme was purified and characterized from W. Somnifera, a popular medicinal plant in South East Asia and Southern Europe. Purification was carried out by a combination of protein precipitation with ammonium sulfate as well as Sephadex-gel filtration. The purified enzyme is a homodimer, with a molecular mass of 72±0.5 kDa as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresisand size exclusion chromatography. The enzyme has a pH optimum of 8.5 and an optimum temperature of 37℃. The Km value for the enzyme is 6.1×10-2 mmol/L. This is the first report for L-asparaginase from W. Somnifera, a traditionally used Indian medicinal plant.

Purification, characterization and antiproliferative activity of l-asparaginase from Aspergillus oryzae CCT 3940 with no glutaminase activity

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Fernanda Furlan Gonçalves Dias

2016-09-01

Conclusions: The sensitivity of the cells lines to purified l-asparaginase from A. oryzae CCT 3940 appeared to be concentration dependent affording a more significant decrease in cell growth than that observed for the commercial l-asparaginase from Escherichia coli. The l-asparaginase from A. oryzae CCT 3940 has a high potential for pharmaceutical exploitation in the treatment of leukemia.

Asparaginase-associated pancreatitis is not predicted by hypertriglyceridemia or pancreatic enzyme levels in children with acute lymphoblastic leukemia

DEFF Research Database (Denmark)

Raja, Raheel Altaf; Schmiegelow, Kjeld; Sørensen, Ditte Nørbo

2017-01-01

Background: l-Asparaginase is an important drug for treatment of childhood acute lymphoblastic leukemia (ALL), but is associated with serious toxicities, including pancreatitis and hypertriglyceridemia (HTG). Asparaginase-associated pancreatitis (AAP) is a common reason for stopping asparaginase...... treatment. The aim of this study was to explore if HTG or early elevations in pancreatic enzymes were associated with the subsequent development of AAP. Method: Children (1.0–17.9 years) diagnosed with ALL, treated with asparaginase for 30 weeks, according to the NOPHO ALL2008 protocol at the University...

Tackling Critical Catalytic Residues in Helicobacter pylori L-Asparaginase

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Maristella Maggi

2015-03-01

Full Text Available Bacterial asparaginases (amidohydrolases, EC 3.5.1.1 are important enzymes in cancer therapy, especially for Acute Lymphoblastic Leukemia. They are tetrameric enzymes able to catalyze the deamination of L-ASN and, to a variable extent, of L-GLN, on which leukemia cells are dependent for survival. In contrast to other known L-asparaginases, Helicobacter pylori CCUG 17874 type II enzyme (HpASNase is cooperative and has a low affinity towards L-GLN. In this study, some critical amino acids forming the active site of HpASNase (T16, T95 and E289 have been tackled by rational engineering in the attempt to better define their role in catalysis and to achieve a deeper understanding of the peculiar cooperative behavior of this enzyme. Mutations T16E, T95D and T95H led to a complete loss of enzymatic activity. Mutation E289A dramatically reduced the catalytic activity of the enzyme, but increased its thermostability. Interestingly, E289 belongs to a loop that is very variable in L-asparaginases from the structure, sequence and length point of view, and which could be a main determinant of their different catalytic features.

L-asparaginase treatment in acute lymphoblastic leukemia

NARCIS (Netherlands)

R. Pieters (Rob); S.P. Hunger (Stephen); J. Boos (Joachim); C. Rizzari (Carmelo); L.B. Silverman (Lewis); A. Baruchel (André); N. Goekbuget (Nicola); M. Schrappe (Martin); C.H. Pui (Ching-Hon)

2011-01-01

textabstractAsparaginases are a cornerstone of treatment protocols for acute lymphoblastic leukemia (ALL) and are used for remission induction and intensification treatment in all pediatric regimens and in the majority of adult treatment protocols. Extensive clinical data have shown that intensive

Optimizing the dosing schedule of l-asparaginase improves its anti-tumor activity in breast tumor-bearing mice

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Shoya Shiromizu

2018-04-01

Full Text Available Proliferation of acute lymphoblastic leukemic cells is nutritionally dependent on the external supply of asparagine. l-asparaginase, an enzyme hydrolyzing l-asparagine in blood, is used for treatment of acute lymphoblastic leukemic and other related blood cancers. Although previous studies demonstrated that l-asparaginase suppresses the proliferation of cultured solid tumor cells, it remains unclear whether this enzyme prevents the growth of solid tumors in vivo. In this study, we demonstrated the importance of optimizing dosing schedules for the anti-tumor activity of l-asparaginase in 4T1 breast tumor-bearing mice. Cultures of several types of murine solid tumor cells were dependent on the external supply of asparagine. Among them, we selected murine 4T1 breast cancer cells and implanted them into BALB/c female mice kept under standardized light/dark cycle conditions. The growth of 4T1 tumor cells implanted in mice was significantly suppressed by intravenous administration of l-asparaginase during the light phase, whereas its administration during the dark phase failed to show significant anti-tumor activity. Decreases in plasma asparagine levels due to the administration of l-asparaginase were closely related to the dosing time-dependency of its anti-tumor effects. These results suggest that the anti-tumor efficacy of l-asparaginase in breast tumor-bearing mice is improved by optimizing the dosing schedule. Keywords: l-asparaginase, Asparagine, Solid tumor, Chrono-pharmacotherapy

Purification and properties of asparaginase from the testa of immature seeds of pea (Pisum sativum L.

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Chagas Eliana P.

2001-01-01

Full Text Available A K+-dependent asparaginase (E.C. 3.5.1.1. was purified 1328-fold from the testas of immature pea seeds (Pisum sativum L., var. Bolero and characterized. Antibodies raised against purified asparaginase cross-reacted with the putative asparaginase band in Western blot analyses of semi-purified extracts. However, for crude extracts of pea testas, a cross-reaction was obtained with at least four protein bands, one of which was asparaginase protein. Affinity-purified antibodies to the four strongest bands of crude extracts were fairly specific for the bands from which they were purified, suggesting a mixture of specific antibodies. The Mr of asparaginase was 69,000 by Sephacryl S200 chromatography and also by mobility on native PAGE relative to BSA. There was no evidence for dissociation into subunits on SDS-PAGE, suggesting a monomeric protein of Mr 69,000. Other properties include an apparent Km of 2.4 mM, pI between 4.5 and 5, and competitive inhibition by aspartate and glycine.

Outcomes Following Discontinuation of E. coli l-Asparaginase Upon Severe Allergic Reactions in Children With Acute Lymphoblastic Leukemia.

Science.gov (United States)

Yen, Hsiu-Ju; Chang, Wan-Hui; Liu, Hsi-Che; Yeh, Ting-Chi; Hung, Giun-Yi; Wu, Kang-Hsi; Peng, Ching-Tien; Chang, Yu-Hsiang; Chang, Te-Kao; Hsiao, Chih-Cheng; Sheen, Jiunn-Ming; Chao, Yu-Hua; Chang, Tai-Tsung; Chiou, Shyh-Shin; Lin, Pei-Chin; Wang, Shih-Chung; Lin, Ming-Tsan; Ho, Wan-Ling; Chen, Yu-Chieh; Liang, Der-Cherng

2016-04-01

Discontinuation of E. coli l-asparaginase in patients with acute lymphoblastic leukemia (ALL) is unavoidable upon severe allergic reaction. We sought to examine outcomes following E. coli l-asparaginase discontinuation due to severe allergic reactions. We evaluated the outcome of children enrolled in Taiwan Pediatric Oncology Group-2002-ALL protocol between 2002 and 2012, who had E. coli l-asparaginase discontinued due to severe allergic reactions, and compared the outcomes of those who continued with Erwinia l-asparaginase (Erwinase) with those who did not. Among 700 patients enrolled in this study, 33 patients had E. coli l-asparaginase treatment discontinued due to severe allergic reactions. Five-year overall survival did not differ significantly among the 648 patients without discontinuation (81 ± 1.6%, mean ± SE), compared to 17 patients with allergic reactions and treated with Erwinase (88 ± 7.8%) and 16 patients with allergic reactions but not treated with Erwinase (87 ± 8.6%). Among 16 patients who did not receive Erwinase, all 10 who received ≥50% of the scheduled doses of E. coli l-asparaginase before discontinuation survived without events. Erwinase treatment may not be needed for some ALL patients with severe allergy to E. coli l-asparaginase if ≥50% of prescribed doses were received and/or therapy is augmented with other agents. © 2015 Wiley Periodicals, Inc.

Protracted Administration of L-Asparaginase in Maintenance Phase Is the Risk Factor for Hyperglycemia in Older Patients with Pediatric Acute Lymphoblastic Leukemia

Science.gov (United States)

Yoshida, Hideki; Imamura, Toshihiko; Saito, Akiko M.; Takahashi, Yoshihiro; Suenobu, So-ichi; Hasegawa, Daiichiro; Deguchi, Takao; Hashii, Yoshiko; Kawasaki, Hirohide; Endo, Mikiya; Hori, Hiroki; Suzuki, Nobuhiro; Kosaka, Yoshiyuki; Kato, Koji; Yumura-Yagi, Keiko; Hara, Junichi; Oda, Megumi; Sato, Atsushi; Horibe, Keizo

2015-01-01

Although L-asparaginase related hyperglycemia is well known adverse event, it is not studied whether the profile of this adverse event is affected by intensification of L-asparaginase administration. Here, we analyzed the profile of L-asparaginase related hyperglycemia in a 1,176 patients with pediatric acute lymphoblastic leukemia treated according to the Japan Association of Childhood Leukemia Study ALL-02 protocol using protracted L-asparaginase administration in maintenance phase. We determined that a total of 75 L-asparaginase related hyperglycemia events occurred in 69 patients. Although 17 events (17/1176, 1.4%) developed in induction phase, which was lower incidence than those (10–15%) in previous reports, 45 events developed during the maintenance phase with protracted L-asparaginase administration. Multivariate analysis showed that older age at onset (≥10 years) was a sole independent risk factor for L-asparaginase-related hyperglycemia (Phyperglycemia. These findings suggest that protracted administration of L-asparaginase is the risk factor for hyperglycemia when treating adolescent and young adult acute lymphoblastic leukemia patients. PMID:26317422

Direct long-term effects of L-asparaginase on rat and human pancreatic islets

DEFF Research Database (Denmark)

Clausen, Niels; Nielsen, Jens Høiriis

1989-01-01

L-Asparaginase, an effective agent in the treatment of acute lymphoblastic leukemia, may induce a diabetic state. The pathogenesis of the diabetogenic effect was studied in cultured pancreatic islets. Mean serum concentrations in three children with acute lymphoblastic leukemia were 2.4 U/mL (range...... the glucagon content was unchanged. Removal of the drug resulted in partial recovery of the insulin secretion. To elucidate the mechanisms of of action of the drug, insulin biosynthesis was studied in islets cultured in asparagine-free medium with or without asparaginase. No difference in biosynthesis was seen...... between media with or without asparagine, whereas 0.1 U/mL asparaginase caused about a 50% reduction under both conditions.(ABSTRACT TRUNCATED AT 250 WORDS)...

Effect of L-asparaginase on acrylamide mitigation in a fried-dough pastry model.

Science.gov (United States)

Kukurová, Kristína; Morales, Francisco J; Bednáriková, Alena; Ciesarová, Zuzana

2009-12-01

A dough resembling traditional Spanish rosquillas was used as a model to represent classical fried-dough pastry to investigate the effects of asparaginase and heat treatment on amino acid levels and acrylamide mitigation. Wheat-based dough was deep fried at 180 and 200 degrees C for 4, 6, and 8 min. Two recipes were formulated by addition of different asparaginase levels (100 and 500 U/kg flour) to the dough. The temperature/time profile of the frying process, moisture, sugars, amino acids, acrylamide, and some indicators of the Maillard reaction (hydroxymethylfurfural, color, free fluorescence compounds, and browning) were determined to investigate the extent of the reaction and the effect on reactants. At the both levels of asparaginase used, 96-97% of the asparagine present was converted to aspartic acid, and consequently the acrylamide level was very efficiently reduced (up to 90%). The asparaginase also affected the content of glutamine and glutamic acid in dough, resulting in a 37% increase in glutamic acid compared with the untreated sample. Concerning color, browning and Maillard reaction parameters, no significant changes between untreated and enzymatically treated samples were observed, pointing out the potential industrial and domestic enzyme application.

Prolonged first-line PEG-asparaginase treatment in pediatric acute lymphoblastic leukemia in the NOPHO ALL2008 protocol-Pharmacokinetics and antibody formation

DEFF Research Database (Denmark)

Tram Henriksen, Louise; Gottschalk Højfeldt, Sofie; Schmiegelow, Kjeld

2017-01-01

BACKGROUND: As pegylated asparaginase is becoming the preferred first-line asparaginase preparation in the chemotherapy regimens of childhood acute lymphoblastic leukemia (ALL), there is a need to evaluate this treatment. METHODS: The aim of this study was to evaluate the pharmacokinetics...... of prolonged upfront biweekly PEG-asparaginase (where PEG is polyethylene glycol) treatment by measuring serum l-asparaginase activity and formation of anti-PEG-asparaginase antibodies. A total of 97 evaluable patients (1-17 years), diagnosed with ALL, and treated according to the NOPHO ALL2008 protocol (where...... NOPHO is Nordic Society of Paediatric Haematology and Oncology) were included. In the NOPHO ALL2008 protocol, patients are randomized to 8 or 15 doses of intramuscular PEG-asparaginase (Oncaspar(®) ) 1,000 IU/m²/dose, at 2-week or 6-week intervals with a total of 30-week treatment (Clinical trials...

Efficacy and Toxicity of Asparaginases During Prospective Drug Monitoring in Patients With Childhood Acute Lymphoblastic Leukemia

NARCIS (Netherlands)

W.H. Tong (Wing)

2014-01-01

markdownabstract__Abstract__ Intensified and effective asparaginase therapy is very important in modern treatment of childhood acute lymphoblastic leukemia. The use of native E.coli asparaginase in induction leads to a high rate of hypersensitivity reactions to PEGasparaginase in the

Hypersensitivity reactions associated with L-asparaginase administration in 142 dogs and 68 cats with lymphoid malignancies: 2007-2012.

Science.gov (United States)

Blake, Mary Kay; Carr, Brittany J; Mauldin, Glenna E

2016-02-01

Clinically significant hypersensitivity reactions (HSRs) to the chemotherapy drug L-asparaginase are reported in humans and dogs, but frequency in small animals is not well-defined. This study retrospectively evaluated the frequency of HSR to L-asparaginase given by IM injection to dogs and cats with lymphoid malignancies. The medical records of all dogs and cats treated with at least 1 dose of L-asparaginase chemotherapy over a 5-year period were reviewed. A total of 370 doses of L-asparaginase were administered to the dogs, with 88 of 142 dogs receiving multiple doses, and 6 dogs experiencing an HSR. A total of 197 doses were administered to the cats, with 33 of 68 cats receiving multiple doses, and no cats experiencing an HSR. Hypersensitivity reactions were documented in 4.2% of dogs, and in association with 1.6% of L-asparaginase doses administered. These results show that HSRs occur uncommonly among dogs and cats, even with repeated dosing.

Production of Extracellular Anti-leukaemic Enzyme L- asparaginase ...

African Journals Online (AJOL)

Erah

asparaginase, Solid-state media, TGY broth, TFY broth, SDS-PAGE, ... to contamination, ease of product extraction ... producing property of isolates; organic nitrate ... water, to 100 ml, and contained in a 250 ml .... carbon utilization and nitrogen utilization.

PEG-asparaginase allergy in children with acute lymphoblastic leukemia in the NOPHO ALL2008 protocol

DEFF Research Database (Denmark)

Henriksen, Louise Tram; Harila-Saari, Arja; Ruud, Ellen

2014-01-01

BACKGROUND: L-Asparaginase is an effective drug in the treatment of childhood acute lymphoblastic leukemia (ALL). The use of L-asparaginase may be limited by serious adverse events of which allergy is the most frequent. The objective of this study was to describe the clinical aspects of PEG...

Serial Ultrasound Monitoring for Early Recognition of Asparaginase Associated Pancreatitis in Children With Acute Lymphoblastic Leukemia

DEFF Research Database (Denmark)

Raja, Raheel Altaf; Schmiegelow, K.; Henriksen, Birthe Merete

2015-01-01

BACKGROUND: Acute lymphoblastic leukemia (ALL) is the most common cancer in children and L-asparaginase is an essential component of the treatment. Cessation of L-asparaginase decreases event free survival. Acute pancreatitis is the toxicity that most commonly results in cessation of L...

Production of L-Asparaginase by the marine luminous bacteria

Digital Repository Service at National Institute of Oceanography (India)

Ramaiah, N.; Chandramohan, D.

Fortythree strains of luminous bacteria, belonging to 4 species, (Vibrio harveyi, V. fischeri, Photobacterium leiognathi and P. phosphoreum) isolated from different marine samples, were examined for the production of L-asparaginase. Presence...

Safety, efficacy, and clinical utility of asparaginase in the treatment of adult patients with acute lymphoblastic leukemia

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Koprivnikar J

2017-03-01

Full Text Available Jamie Koprivnikar, James McCloskey, Stefan Faderl Division of Leukemia, John Theurer Cancer Center at Hackensack University Medical Center, Hackensack, NJ, USA Abstract: Adults with acute lymphoblastic leukemia (ALL are known to have inferior outcomes compared to the pediatric population. Although the reasons for this are likely manyfold, the agents utilized and the increased intensity of pediatric treatments compared to adult treatments are likely significant contributing factors. Asparaginase, an enzyme that converts asparagine to aspartic acid, forms the backbone of almost all pediatric regimens and works by depleting extracellular asparagine, which ALL cells are unable to synthesize. Asparaginase toxicities, which include hypersensitivity reactions, pancreatitis, liver dysfunction, and thrombosis, have hindered its widespread use in the adult population. Here, we review the toxicity and efficacy of asparaginase in adult patients with ALL. With the proper precautions, it is a safe and effective agent in the treatment of younger adults with ALL with response rates in the frontline setting ranging from 78% to 96%, compared to most trials showing a 4-year overall survival of 50% or better. The age cutoff for consideration of treatment with pediatric-inspired regimens is not clear, but recent studies show promise particularly in the adolescent and young adult population. New formulations of asparaginase are actively in development, including erythrocyte-encapsulated asparaginase, which is designed to minimize the toxicity and improve the delivery of the drug. Keywords: PEG-asparaginase, ALL, chemotherapy, pegaspargase, AYA, pediatric 

Optimizing the dosing schedule of l-asparaginase improves its anti-tumor activity in breast tumor-bearing mice.

Science.gov (United States)

Shiromizu, Shoya; Kusunose, Naoki; Matsunaga, Naoya; Koyanagi, Satoru; Ohdo, Shigehiro

2018-04-01

Proliferation of acute lymphoblastic leukemic cells is nutritionally dependent on the external supply of asparagine. l-asparaginase, an enzyme hydrolyzing l-asparagine in blood, is used for treatment of acute lymphoblastic leukemic and other related blood cancers. Although previous studies demonstrated that l-asparaginase suppresses the proliferation of cultured solid tumor cells, it remains unclear whether this enzyme prevents the growth of solid tumors in vivo. In this study, we demonstrated the importance of optimizing dosing schedules for the anti-tumor activity of l-asparaginase in 4T1 breast tumor-bearing mice. Cultures of several types of murine solid tumor cells were dependent on the external supply of asparagine. Among them, we selected murine 4T1 breast cancer cells and implanted them into BALB/c female mice kept under standardized light/dark cycle conditions. The growth of 4T1 tumor cells implanted in mice was significantly suppressed by intravenous administration of l-asparaginase during the light phase, whereas its administration during the dark phase failed to show significant anti-tumor activity. Decreases in plasma asparagine levels due to the administration of l-asparaginase were closely related to the dosing time-dependency of its anti-tumor effects. These results suggest that the anti-tumor efficacy of l-asparaginase in breast tumor-bearing mice is improved by optimizing the dosing schedule. Copyright © 2018 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

Hypersensitivity reactions associated with L-asparaginase administration in 142 dogs and 68 cats with lymphoid malignancies: 2007–2012

Science.gov (United States)

Blake, Mary Kay; Carr, Brittany J.; Mauldin, Glenna E.

2016-01-01

Clinically significant hypersensitivity reactions (HSRs) to the chemotherapy drug L-asparaginase are reported in humans and dogs, but frequency in small animals is not well-defined. This study retrospectively evaluated the frequency of HSR to L-asparaginase given by IM injection to dogs and cats with lymphoid malignancies. The medical records of all dogs and cats treated with at least 1 dose of L-asparaginase chemotherapy over a 5-year period were reviewed. A total of 370 doses of L-asparaginase were administered to the dogs, with 88 of 142 dogs receiving multiple doses, and 6 dogs experiencing an HSR. A total of 197 doses were administered to the cats, with 33 of 68 cats receiving multiple doses, and no cats experiencing an HSR. Hypersensitivity reactions were documented in 4.2% of dogs, and in association with 1.6% of L-asparaginase doses administered. These results show that HSRs occur uncommonly among dogs and cats, even with repeated dosing. PMID:26834270

Marine microbial L-asparaginase: Biochemistry, molecular approaches and applications in tumor therapy and in food industry.

Science.gov (United States)

Izadpanah Qeshmi, Fatemeh; Homaei, Ahmad; Fernandes, Pedro; Javadpour, Sedigheh

2018-03-01

The marine environment is a rich source of biological and chemical diversity. It covers more than 70% of the Earth's surface and features a wide diversity of habitats, often displaying extreme conditions, where marine organisms thrive, offering a vast pool for microorganisms and enzymes. Given the dissimilarity between marine and terrestrial habitats, enzymes and microorganisms, either novel or with different and appealing features as compared to terrestrial counterparts, may be identified and isolated. L-asparaginase (E.C. 3.5.1.1), is among the relevant enzymes that can be obtained from marine sources. This amidohydrolase acts on L-asparagine and produce L-aspartate and ammonia, accordingly it has an acknowledged chemotherapeutic application, namely in acute lymphoblastic leukemia. Moreover, L-asparaginase is also of interest in the food industry as it prevents acrylamide formation. Terrestrial organisms have been largely tapped for L-asparaginases, but most failed to comply with criteria for practical applications, whereas marine sources have only been marginally screened. This work provides an overview on the relevant features of this enzyme and the framework for its application, with a clear emphasis on the use of L-asparaginase from marine sources. The review envisages to highlight the unique properties of marine L-asparaginases that could make them good candidates for medical applications and industries, especially in food safety. Copyright © 2018 Elsevier GmbH. All rights reserved.

Engineering of Helicobacter pylori L-asparaginase: characterization of two functionally distinct groups of mutants.

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Maristella Maggi

Full Text Available Bacterial L-asparaginases have been used as anti-cancer drugs for over 4 decades though presenting, along with their therapeutic efficacy, several side effects due to their bacterial origin and, seemingly, to their secondary glutaminase activity. Helicobacter pylori type II L-asparaginase possesses interesting features, among which a reduced catalytic efficiency for L-GLN, compared to the drugs presently used in therapy. In the present study, we describe some enzyme variants with catalytic and in vitro cytotoxic activities different from the wild type enzyme. Particularly, replacements on catalytic threonines (T16D and T95E deplete the enzyme of both its catalytic activities, once more underlining the essential role of such residues. One serendipitous mutant, M121C/T169M, had a preserved efficiency vs L-asparagine but was completely unable to carry out L-glutamine hydrolysis. Interestingly, this variant did not exert any cytotoxic effect on HL-60 cells. The M121C and T169M single mutants had reduced catalytic activities (nearly 2.5- to 4-fold vs wild type enzyme, respectively. Mutant Q63E, endowed with a similar catalytic efficiency versus asparagine and halved glutaminase efficiency with respect to the wild type enzyme, was able to exert a cytotoxic effect comparable to, or higher than, the one of the wild type enzyme when similar asparaginase units were used. These findings may be relevant to determine the role of glutaminase activity of L-asparaginase in the anti-proliferative effect of the drug and to shed light on how to engineer the best asparaginase/glutaminase combination for an ever improved, patients-tailored therapy.

Neurosurgical management of L-asparaginase induced haemorrhagic stroke.

LENUS (Irish Health Repository)

Ogbodo, Elisha

2012-01-01

The authors describe a case of L-asparaginase induced intracranial thrombosis and subsequent haemorrhage in a newly diagnosed 30-year-old man with acute lymphoblastic leukaemia who was successfully managed by surgical intervention. At presentation, he had a Glasgow Coma Score of 7\\/15, was aphasic and had dense right hemiplegia. Neuroimaging revealed an acute anterior left middle cerebral artery infarct with parenchymal haemorrhagic conversion, mass effect and subfalcine herniation. He subsequently underwent left frontal craniotomy and evacuation of large frontal haematoma and decompressive craniectomy for cerebral oedema. Six months postoperatively he underwent titanium cranioplasty. He had made good clinical recovery and is currently mobilising independently with mild occasional episodes of expressive dysphasia, difficulty with fine motor movement on the right side, and has remained seizure free. This is the first documented case of L-asparaginase induced haemorrhagic stroke managed by neurosurgical intervention. The authors emphasise the possible role of surgery in managing chemotherapy induced intracranial complications.

Hepatic sinusoidal obstruction syndrome during maintenance therapy of childhood acute lymphoblastic leukemia is associated with continuous asparaginase therapy and mercaptopurine metabolites

DEFF Research Database (Denmark)

Toksvang, Linea Natalie; De Pietri, Silvia; Nielsen, Stine N.

2017-01-01

BACKGROUND: Hepatic sinusoidal obstruction syndrome (SOS) during treatment of childhood acute lymphoblastic leukemia (ALL) has mainly been associated with 6-thioguanine. The occurrence of several SOS cases after the introduction of extended pegylated asparaginase (PEG-asparaginase) therapy...... in the Nordic Society of Paediatric Haematology and Oncology (NOPHO) ALL2008 protocol led us to hypothesize that PEG-asparaginase, combined with other drugs, may trigger SOS during 6-thioguanine-free maintenance therapy. PROCEDURE: In children with ALL treated in Denmark according to the NOPHO ALL2008 protocol...... children receiving PEG-asparaginase biweekly, 29 developed SOS (≥2 criteria: hyperbilirubinemia, hepatomegaly, ascites, weight gain ≥2.5%, unexplained thrombocytopenia

The potential of halophilic and halotolerant bacteria for the production of antineoplastic enzymes: L-asparaginase and L-glutaminase.

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Shirazian, Pejman; Asad, Sedigheh; Amoozegar, Mohammad Ali

2016-01-01

L-asparaginase and L-glutaminase can be effectively used for the treatment of patients who suffer from accute lymphoblastic leukemia and tumor cells. Microbial sources are the best source for the bulk production of these enzymes. However, their long-term administration may cause immunological responses, so screening for new enzymes with novel properties is required. Halophilic and halotolerant bacteria with novel enzymatic characteristics can be considered as a potential source for production of enzymes with different immunological properties. In this study, L-asparaginase and L-glutaminase production by halophilic bacteria isolated from Urmia salt lake was studied. Out of the 85 isolated halophilic and halotolerant bacterial strains, 16 (19 %) showed L-asparaginase activity and 3 strains (3.5 %) showed L-glutaminase activity. Strains with the highest activities were selected for further studies. Based on 16S rDNA sequence analysis, it was shown that the selected isolates for L-asparaginase and L-glutaminase production belong to the genus Bacillus and Salicola, respectively. Both enzymes were produced extracellularly. The strain with the most L-asparaginase production did not show L-glutaminase production which is medically important. The effects of key parameters including temperature, initial pH of the solution, and concentrations of glucose, asparagine or glutamine, and sodium chloride were evaluated by means of response surface methodology (RSM) to optimize enzymes production. Under the obtained optimal conditions, L-asparaginase and L-glutaminase production was increased up to 1.5 (61.7 unit/mL) and 2.6 fold (46.4 unit/mL), respectively.

Acrylamide diminishing in potato chips by using commercial Asparaginase

DEFF Research Database (Denmark)

Pedreschi, Franco; Mariotti, Salomé; Granby, Kit

2011-01-01

In April 2002, Swedish researchers shocked the food safety world when they presented preliminary findings of acrylamide in some fried and baked foods, most notably potato chips and French fries. Asparagine is an aminoacid precursor of acrylamide formation through Maillard reaction. Asparaginase e...

Population pharmacokinetics of intravenous Erwinia asparaginase in pediatric acute lymphoblastic leukemia patients.

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Sassen, Sebastiaan D T; Mathôt, Ron A A; Pieters, Rob; Kloos, Robin Q H; de Haas, Valérie; Kaspers, Gertjan J L; van den Bos, Cor; Tissing, Wim J E; Te Loo, Maroeska; Bierings, Marc B; Kollen, Wouter J W; Zwaan, Christian M; van der Sluis, Inge M

2017-03-01

Erwinia asparaginase is an important component in the treatment of pediatric acute lymphoblastic leukemia. A large variability in serum concentrations has been observed after intravenous Erwinia asparaginase. Currently, Dutch Childhood Oncology Group protocols dose alterations are based on trough concentrations to ensure adequate asparaginase activity (≥100 IU/L). The aim of this study was to describe the population pharmacokinetics of intravenous Erwinia asparaginase to quantify and gather insight into inter-individual and inter-occasion variability. The starting dose was evaluated on the basis of the derived population pharmacokinetic parameters. In a multicenter prospective observational study, a total of 714 blood samples were collected from 51 children (age 1-17 years) with acute lymphoblastic leukemia. The starting dose was 20,000 IU/m 2 three times a week and adjusted according to trough levels from week three onwards. A population pharmacokinetic model was developed using NONMEM ® A 2-compartment linear model with allometric scaling best described the data. Inter-individual and inter-occasion variability of clearance were 33% and 13%, respectively. Clearance in the first month of treatment was 14% higher ( P <0.01). Monte Carlo simulations with our pharmacokinetic model demonstrated that patients with a low weight might require higher doses to achieve similar concentrations compared to patients with high weight. The current starting dose of 20,000 IU/m 2 might result in inadequate concentrations, especially for smaller, lower weight patients, hence dose adjustments based on individual clearance are recommended. The protocols were approved by the institutional review boards. (Registered at NTR 3379 Dutch Trial Register; www.trialregister.nl). Copyright© Ferrata Storti Foundation.

Asparaginase II-GFP fusion as a tool for studying the secretion of the enzyme under nitrogen starvation Fusão asparaginase II-GFP como ferramenta para estudo da via secretora de enzima sobre depleção por nitrogênio

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Adriana Sotero-Martins

2003-12-01

Full Text Available Production of asparaginase II of Saccharomyces cerevisiae is regulated by nitrogen and can be used as a model system for studying other secreted proteins in yeast. Green fluorescent protein (GFP from Aequorea victoria was fused to the carboxy-terminus of the enzyme by genomic integration to the locus ASP3 of S. cerevisiae. We determined asparaginase II activity, mRNA ASP3, mRNA ASP3-GFP and GFP fluorescence. Nitrogen starvation in cells carrying the chimera ASP3-GFP caused an increase in fluorescence and in the expression of ASP3. We have shown that cells producing the chimera Asp3-GFPp displayed the same response to nitrogen starvation as control cells. We demonstrated that Asp3-GFPp can be used for studying asparaginase II secretion under nitrogen starvation in vivo.A produção de asparaginase II de Saccharomyces cerevisiae é regulada por nitrogênio e pode ser utilizada como um sistema modelo para estudar outras proteínas secretadas, em leveduras. A proteína "green fluorescent protein" (GFP de Aequorea victoria foi fusionada à porção carboxi-terminal de Asp3p por integração genômica da sequência de GFP ao locus ASP3. Determinaram-se os níveis de atividade de asparaginase II, mRNA ASP3, mRNA ASP3-GFP e de fluorescência para GFP. A depleção para nitrogênio, em células portadoras do gene quimérico ASP3-GFP, fez aumentar a fluorescência, assim como a expressão de ASP3. Demonstramos que Asp3-GFPp pode ser utilizada para estudar a secreção de asparaginase II em células submetidas à privação de nitrogênio in vivo.

Purification, characterization, cytotoxicity and anticancer activities of L-asparaginase, anti-colon cancer protein, from the newly isolated alkaliphilic Streptomyces fradiae NEAE-82

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El-Naggar, Noura El-Ahmady; Deraz, Sahar F.; Soliman, Hoda M.; El-Deeb, Nehal M.; El-Ewasy, Sara M.

2016-01-01

L-asparaginase is an important enzyme as therapeutic agents used in combination with other drugs in the treatment of acute lymphoblastic leukemia. A newly isolated actinomycetes strain, Streptomyces sp. NEAE-82, was potentially producing extracellular L-asparaginase, it was identified as Streptomyces fradiae NEAE-82, sequencing product was deposited in the GenBank database under accession number KJ467538. L-asparaginase was purified from the crude enzyme using ammonium sulfate precipitation, dialysis and ion exchange chromatography using DEAE Sepharose CL-6B. Further the kinetic studies of purified enzyme were carried out. The optimum pH, temperature and incubation time for maximum L-asparaginase activity were found to be 8.5, 40 °C and 30 min, respectively. The optimum substrate concentration was found to be 0.06 M. The Km and Vmax of the enzyme were 0.01007 M and 95.08 Uml−1min−1, respectively. The half-life time (T1/2) was 184.91 min at 50 °С, while being 179.53 min at 60 °С. The molecular weight of the subunits of L-asparaginase was found to be approximately 53 kDa by SDS–PAGE analysis. The purified L-asparaginase showed a final specific activity of 30.636 U/mg protein and was purified 3.338-fold. The present work for the first time reported more information in the production, purification and characterization of L-asparaginase produced by newly isolated actinomycetes Streptomyces fradiae NEAE-82. PMID:27605431

Acrylamide reduction in potato chips by using commercial asparaginase in combination with conventional blanching

DEFF Research Database (Denmark)

Pedreschi, Franco; Mariotti, Salomé; Granby, Kit

2011-01-01

In this research acrylamide reduction in potato chips was investigated in relation to blanching and asparaginase immersion treatments before final frying. Potatoes slices (Verdi variety, diameter: 40 mm, thickness: 2.0 mm) were fried at 170 °C for 5 min (final moisture content of ∼2.0 g/100 g......). Prior to frying, potato slices were treated in one of the following ways: (i) Rinsing in distilled water (control I); (ii) Rinsing in distilled water plus blanching in hot water at 85 °C for 3.5 min; (iii) Rinsing in distilled water plus immersion in an asparaginase solution (10000 ASNU/L) at 50 °C...... for 20 min; (iv) Rinsing in distilled water plus blanching in hot water at 85 °C for 3.5 min plus immersion in an asparaginase solution (10000 ASNU/L) at 50 °C for 20 min; (v) Rinsing in distilled water plus blanching in hot water at 85 °C for 3.5 min plus immersion in distilled water at 50 °C for 20 min...

Arabidopsis mutants lacking asparaginases develop normally but exhibit enhanced root inhibition by exogenous asparagine.

Science.gov (United States)

Ivanov, Ana; Kameka, Alexander; Pajak, Agnieszka; Bruneau, Luanne; Beyaert, Ronald; Hernández-Sebastià, Cinta; Marsolais, Frédéric

2012-06-01

Asparaginase catalyzes the degradation of L-asparagine to L-aspartic acid and ammonia, and is implicated in the catabolism of transported asparagine in sink tissues of higher plants. The Arabidopsis genome includes two genes, ASPGA1 and ASPGB1, belonging to distinct asparaginase subfamilies. Conditions of severe nitrogen limitation resulted in a slight decrease in seed size in wild-type Arabidopsis. However, this response was not observed in a homozygous T-DNA insertion mutant where ASPG genes had been inactivated. Under nitrogen-sufficient conditions, the ASPG mutant had elevated levels of free asparagine in mature seed. This phenotype was observed exclusively under conditions of low illumination, when a low ratio of carbon to nitrogen was translocated to the seed. Mutants deficient in one or both asparaginases were more sensitive than wild-type to inhibition of primary root elongation and root hair emergence by L-asparagine as a single nitrogen source. This enhanced inhibition was associated with increased accumulation of asparagine in the root of the double aspga1-1/-b1-1 mutant. This indicates that inhibition of root growth is likely elicited by asparagine itself or an asparagine-derived metabolite, other than the products of asparaginase, aspartic acid or ammonia. During germination, a fusion between the ASPGA1 promoter and beta-glucuronidase was expressed in endosperm cells starting at the micropylar end. Expression was initially high throughout the root and hypocotyl, but became restricted to the root tip after three days, which may indicate a transition to nitrogen-heterotrophic growth.

Low Bioavailability and High Immunogenicity of a New Brand of E. coli l-Asparaginase with Active Host Contaminating Proteins

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Priscila Pini Zenatti

2018-04-01

Full Text Available The drug l-asparaginase is a cornerstone in the treatment of acute lymphoblastic leukemia (ALL. The native E. coli l-asparaginase used in Brazil until recently has been manufactured by Medac/Kyowa. Then a decision was taken by the Ministry of Health in 2017 to supply the National Health System with a cheaper alternative l-asparaginase manufactured by Beijing SL Pharmaceutical, called Leuginase®. As opposed to Medac, the asparaginase that has been in use in Brazil under the trade name of Aginasa®, it was not possible to find a single entry with the terms Leuginase in the Pubmed repository. The apparent lack of clinical studies and the scarcity of safety information provided to the hospitals by the drug distributor created a debate among Brazilian pediatric oncologists about issues of safety and efficacy that culminated eventually in a court decision to halt the distribution of the new drug all over the country. Boldrini Children's Center, a non-profit pediatric oncohematology hospital, has conducted its own evaluation of Leuginase®. Mass spectrometry analyses found at least 12 different contaminating host-cell proteins (HCP in Leuginase®. The presence of two HCP (beta-lactamase and malate dehydrogenase was confirmed by orthogonal methodologies. The relative number of HCP peptides ranged from 19 to 37% of the total peptides identified by mass spectrometry. In vivo studies in mice injected with Leuginase® revealed a 3 times lower plasma bioavailability and the development of higher antibody titres against l-asparaginase in comparison to Aginasa®-injected animals. The decision to buy a new drug based on its price alone is not safe. Developing countries are especially vulnerable to cheaper alternatives that lack solid quality assurance. Keywords: l-Asparaginase, Host contaminant proteins, Mass spectrometry, Bioavailability, Immunogenicity

Production, purification and characterization of L-asparaginase from Streptomyces gulbargensis

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S. Amena

2010-03-01

Full Text Available L-asparaginase is an anti-neoplastic agent used in the lymphoblastic leukaemia chemotherapy. In the present study a novel strain, Streptomyces gulbargensis was explored for the production of extra-cellular L-asparaginase using groundnut cake extract. The optimum pH, temperature, inoculum size and agitation speed for enzyme production were pH 8.5, 40ºC, 1x10(8spores/ml and 200 rev/min respectively. Maltose (0.5% and L-asparagine (0.5% proved to be the best carbon and nitrogen sources respectively. The enzyme was purified 82.12 fold and the apparent molecular weight of the enzyme was found to be 85 kDa. The optima pH and temperature for the enzyme were 9.0 and 40ºC respectively. The enzyme was more stable at the alkaline pH than at the acidic one and it retained 55% of the activity at 80ºC for 60 min.

The Effects of L-Asparaginase on Blood Triglycerides, Glucose, and Albumin Levels and Coagulation State in ALL Patients in Pediatric Ward

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Heydarian Farhad

2009-10-01

Full Text Available Asparaginase is one of the most important agents in the treatment of ALL. However, it has some side effects including dislipidemia, hyperglycemia, coagulopathy and hepatotoxicity. We studied its side ef-fects on our patients. The effects of L-asparaginase were assessed on 25 new ALL patients (case group and 25 patients with known ALL who had completed their treatment before. Sixty two percent of cases were male and remainder was female. The mean age of patients was 7.2 ± 3.8 years. In our patients, there was a rise in triglycerides (TG was seen following L- asparaginase administration (P = 0.02. Also, PT prolongation (P = 0.02 and hypoalbominemia (P = 0.002 were detected which could PT prolongation and hypoalbuminemia may be seen with L-asparaginase therapy that can be prevented with transfusion of FFP. Hypertriglyceridemia is often asymptomatic with no need for therapy.

"Reagent-free" L-asparaginase activity assay based on CD spectroscopy and conductometry.

Science.gov (United States)

Kudryashova, Elena V; Sukhoverkov, Kirill V

2016-02-01

A new method to determine the catalytic parameters of L-asparaginase using circular dichroism spectroscopy (CD spectroscopy) has been developed. The assay is based on the difference in CD signal between the substrate (L-asparagine) and the product (L-aspartic acid) of enzymatic reaction. CD spectroscopy, being a direct method, enables continuous measurement, and thus differentiates from multistage and laborious approach based on Nessler's method, and overcomes limitations of conjugated enzymatic reaction methods. In this work, we show robust measurements of L-asparaginase activity in conjugates with PEG-chitosan copolymers, which otherwise would not have been possible. The main limitation associated with the CD method is that the analysis should be performed at substrate saturation conditions (V max regime). For K M measurement, the conductometry method is suggested, which can serve as a complimentary method to CD spectroscopy. The activity assay based on CD spectroscopy and conductometry was successfully implicated to examine the catalytic parameters of L-asparaginase conjugates with chitosan and its derivatives, and for optimization of the molecular architecture and composition of such conjugates for improving biocatalytic properties of the enzyme in the physiological conditions. The approach developed is potentially applicable to other enzymatic reactions where the spectroscopic properties of substrate and product do not enable direct measurement with absorption or fluorescence spectroscopy. This may include a number of amino acid or glycoside-transforming enzymes.

Outcome of pediatric patients with acute lymphoblastic leukemia/lymphoblastic lymphoma with hypersensitivity to pegaspargase treated with PEGylated Erwinia asparaginase, pegcrisantaspase: A report from the Children's Oncology Group

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Rau, Rachel E.; Dreyer, ZoAnn; Choi, Mi Rim; Liang, Wei; Skowronski, Roman; Allamneni, Krishna P.; Devidas, Meenakshi; Raetz, Elizabeth A.; Adamson, Peter C.; Blaney, Susan M.; Loh, Mignon L; Hunger, Stephen P.

2018-01-01

Background Erwinia asparaginase is a Food and Drug Administration approved agent for the treatment of acute lymphoblastic leukemia (ALL) for patients who develop hypersensitivity to Escherichia coli derived asparaginases. Erwinia asparaginase is efficacious, but has a short half-life, requiring six doses to replace one dose of the most commonly used first-line asparaginase, pegaspargase, a polyethylene glycol (PEG) conjugated E. coli asparaginase. Pegcristantaspase, a recombinant PEGylated Erwinia asparaginase with improved pharmacokinetics, was developed for patients with hypersensitivity to pegaspargase. Here, we report a series of patients treated on a pediatric phase 2 trial of pegcrisantaspase. Procedure Pediatric patients with ALL or lymphoblastic lymphoma and hypersensitivity to pegaspargase enrolled on Children's Oncology Group trial AALL1421 (Jazz 13-011) and received intravenous pegcrisantaspase. Serum asparaginase activity (SAA) was monitored before and after dosing; immunogenicity assays were performed for antiasparaginase and anti-PEG antibodies and complement activation was evaluated. Results Three of the four treated patients experienced hypersensitivity to pegcrisantaspase manifested as clinical hypersensitivity reactions or rapid clearance of SAA. Immunogenicity assays demonstrated the presence of anti-PEG immunoglobulin G antibodies in all three hypersensitive patients, indicating a PEG-mediated immune response. Conclusions This small series of patients, nonetheless, provides data, suggesting preexisting immunogenicity against the PEG moiety of pegaspargase and poses the question as to whether PEGylation may be an effective strategy to optimize Erwinia asparaginase administration. Further study of larger cohorts is needed to determine the incidence of preexisting antibodies against PEG-mediated hypersensitivity to pegaspargase. PMID:29090524

l-asparaginase-based regimens followed by allogeneic hematopoietic stem cell transplantation improve outcomes in aggressive natural killer cell leukemia

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Ki Sun Jung

2016-04-01

Full Text Available Abstract Aggressive nature killer cell leukemia (ANKL is a mature NK-T cell lymphoma with worse prognosis, but optimal treatment is unclear. Therefore, we analyzed the efficacy of l-asparaginase-based regimens for ANKL patients. Twenty-one patients who received dexamethasone, methotrexate, ifosfamide, l-asparaginase, and etoposide (SMILE or etoposide, ifosfamide, dexamethasone, and l-asparaginase (VIDL chemotherapy at Samsung Medical Center were selected. The overall response rate for all patients was 33 % (7/21; 38 % (5/13 in SMILE and 40 % (2/5 in VIDL, respectively. The median progression-free survival was 3.9 months (95 % CI 0.0–8.1 months and median overall survival was 7.0 months (95 % CI 2.3–11.7 months. Treatment response (P = 0.001, hematopoietic stem cell transplantation (HSCT (P = 0.007 and negative conversion of Epstein-Barr virus (EBV DNA titer after treatment (P = 0.004 were significantly associated with survival. Thus, l-asparaginase-based regimens followed by allogeneic HSCT seem to improve the outcome for ANKL patients.

Acute Pancreatitis and Diabetic Ketoacidosis following L-Asparaginase/Prednisone Therapy in Acute Lymphoblastic Leukemia

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Dania Lizet Quintanilla-Flores

2014-01-01

Full Text Available Acute pancreatitis and diabetic ketoacidosis are unusual adverse events following chemotherapy based on L-asparaginase and prednisone as support treatment for acute lymphoblastic leukemia. We present the case of a 16-year-old Hispanic male patient, in remission induction therapy for acute lymphoblastic leukemia on treatment with mitoxantrone, vincristine, prednisone, and L-asparaginase. He was hospitalized complaining of abdominal pain, nausea, and vomiting. Hyperglycemia, acidosis, ketonuria, low bicarbonate levels, hyperamylasemia, and hyperlipasemia were documented, and the diagnosis of diabetic ketoacidosis was made. Because of uncertainty of the additional diagnosis of acute pancreatitis as the cause of abdominal pain, a contrast-enhanced computed tomography was performed resulting in a Balthazar C pancreatitis classification.

PURIFICATION AND PROPERTIES OF A FUNGAL L-ASPARAGINASE FROM TRICHODERMA VIRIDE PERS: SF GREY

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Lynette Lincoln

2015-02-01

Full Text Available A potent L-asparaginase-producing Trichoderma viride Pers: SF Grey was screened from the marine soil with the objective of studying the enzyme properties. The maximum enzyme production occurred on the third day at pH 6.5 and 37 °C when 0.5% L-asparagine supplemented with 0.5% peptone and 0.6% maltose. The enzyme was purified to homogeneity with a specific activity of 78.2 U.mg-1 and a molecular weight of 99 ± 1 kDa. It exhibited maximum activity at pH 7.0 and 37 °C. It was inhibited by Fe2+, Fe3+, Co2+ and Mn2+ but induced by Mg2+ and Na+. N-ethylemaleimide and phenylmethylsulphonylfluoride did not alter the enzyme activity, but strongly inhibited by ethylenediaminetetraacetate. L-asparaginase showed high affinity for L-asparagine with a Km of 2.56 μM. Thin layer chromatography confirmed the hydrolysis of L-asparagine. As the purified and characterized L-asparaginase of Trichoderma viride showed a good scavenging activity and reduced acrylamide level in potato products, it can further serve as an antileukemic protein and an acrylamide mitigation agent in heat-treated food stuffs rich in carbohydrates, respectively.

Optimization of production of anti-tumor l-asparaginase by free and immobilized marine Aspergillus terreus

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Aida M. Farag

2015-12-01

Full Text Available l-asparaginase plays a vital role in medical application, particularly in treatment of acute lymphoblastic leukemia as an effective anti-tumor agent. In the present study, twenty-one fungal strains were isolated from marine environment of the Red Sea coasts of Egypt. Screening for fungal l-asparaginase production was done, and only five fungal strains were selected and identified as Aspergillus, Penicillium and Fusarium. The most potent fungal isolate was Aspergillus terreus which yielded the highest l-asparaginase specific activity (4.81 U/mg protein. The highest enzyme productivity was observed on the 5th day and the optimized fermentation parameters were pH 6.0, temperature 35 °C. The yield was also high up on using dextrose and asparagine (8.26 U/mg protein as carbon and nitrogen sources. The cultural conditions were studied using the Plackett–Burman experimental design. Immobilization using A. terreus adsorbed on sponge enhanced the enzyme production by 1.33-fold compared to the conventional free-cells. Repeated reuse of the adsorbed cells achieved the maximum enzyme specific activity after three cycles (33.86 U/mg protein.

Synergistic Cytotoxic Effect of L-Asparaginase Combined with Decitabine as a Demethylating Agent in Pediatric T-ALL, with Specific Epigenetic Signature

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Salvatore Serravalle

2016-01-01

Full Text Available T-Acute Lymphoblastic Leukemia (T-ALL remains a subgroup of pediatric ALL, with a lower response to standard chemotherapy. Some recent studies established the fundamental role of epigenetic aberrations such as DNA hypermethylation, to influence patients’ outcome and response to chemotherapy. Moreover, L-asparaginase is an important chemotherapeutic agent for treatment of ALL and resistance to this drug has been linked to ASNS expression, which can be silenced through methylation. Therefore, we tested whether the sensitivity of T-ALL cell lines towards L-asparaginase is correlated to the epigenetic status of ASNS gene and whether the sensitivity can be modified by concurrent demethylating treatment. Hence we treated different T-ALL cell lines with L-asparaginase and correlated different responses to the treatment with ASNS expression. Then we demonstrated that the ASNS expression was dependent on the methylation status of the promoter. Finally we showed that, despite the demethylating effect on the ASNS gene expression, the combined treatment with the demethylating agent Decitabine could synergistically improve the L-asparaginase sensitivity in those T-ALL cell lines characterized by hypermethylation of the ASNS gene. In conclusion, this preclinical study identified an unexpected synergistic activity of L-asparaginase and Decitabine in the subgroup of T-ALL with low ASNS expression due to hypermethylation of the ASNS promoter, while it did not restore sensitivity in the resistant cell lines characterized by higher ASNS expression.

Purification and Characterization of Glutaminase Free Asparaginase from Enterobacter cloacae: In-Vitro Evaluation of Cytotoxic Potential against Human Myeloid Leukemia HL-60 Cells.

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Islam Husain

Full Text Available Asparaginase is an important antileukemic agent extensively used worldwide but the intrinsic glutaminase activity of this enzymatic drug is responsible for serious life threatening side effects. Hence, glutaminase free asparaginase is much needed for upgradation of therapeutic index of asparaginase therapy. In the present study, glutaminase free asparaginase produced from Enterobacter cloacae was purified to apparent homogeneity. The purified enzyme was found to be homodimer of approximately 106 kDa with monomeric size of approximately 52 kDa and pI 4.5. Purified enzyme showed optimum activity between pH 7-8 and temperature 35-40°C, which is close to the internal environment of human body. Monovalent cations such as Na+ and K+ enhanced asparaginase activity whereas divalent and trivalent cations, Ca2+, Mg2+, Zn2+, Mn2+, and Fe3+ inhibited the enzyme activity. Kinetic parameters Km, Vmax and Kcat of purified enzyme were found to be 1.58×10-3 M, 2.22 IU μg-1 and 5.3 × 104 S-1, respectively. Purified enzyme showed prolonged in vitro serum (T1/2 = ~ 39 h and trypsin (T1/2 = ~ 32 min half life, which is therapeutically remarkable feature. The cytotoxic activity of enzyme was examined against a panel of human cancer cell lines, HL-60, MOLT-4, MDA-MB-231 and T47D, and highest cytotoxicity observed against HL-60 cells (IC50 ~ 3.1 IU ml-1, which was comparable to commercial asparaginase. Cell and nuclear morphological studies of HL-60 cells showed that on treatment with purified asparaginase symptoms of apoptosis were increased in dose dependent manner. Cell cycle progression analysis indicates that enzyme induces apoptosis by cell cycle arrest in G0/G1 phase. Mitochondrial membrane potential loss showed that enzyme also triggers the mitochondrial pathway of apoptosis. Furthermore, the enzyme was found to be nontoxic for human noncancerous cells FR-2 and nonhemolytic for human erythrocytes.

Erroneous Exchange of Asparaginase Forms in the Treatment of Acute Lymphoblastic Leukemia

NARCIS (Netherlands)

Cheung, Ka-Chun; van den Bemt, Patricia M. L. A.; Torringa, Maarten L. J.; Tamminga, Rienk Y. J.; Pieters, Rob; de Smet, Peter A. G. M.

For the treatment of children with acute lymphoblastic leukemia (ALL), Dutch pediatric oncologists use the Dutch Childhood Oncology Group ALL 10 protocol. This protocol is complex, as it comprises many different drug regimens. One of the drugs is asparaginase which is available in different forms

Erroneous exchange of asparaginase forms in the treatment of acute lymphoblastic leukemia

NARCIS (Netherlands)

Cheung, K.C.; Bemt, P.M. van den; Torringa, M.L.; Tamminga, R.Y.; Pieters, R.; Smet, P.A. de

2011-01-01

For the treatment of children with acute lymphoblastic leukemia (ALL), Dutch pediatric oncologists use the Dutch Childhood Oncology Group ALL 10 protocol. This protocol is complex, as it comprises many different drug regimens. One of the drugs is asparaginase which is available in different forms

Purification of Escherichia coli L-asparaginase mutants by a native polyacrylamide gel electrophoresis.

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Wei, Yujun; Chen, Jianhua; Jia, Ruibo; Wang, Min; Wu, Wutong

2008-07-01

The antigenicity of L-asaparaginase (L-ASP) has been problematic for the treatment of leukemia for many years. In order to establish a relationship between the antigenic epitope of L-asparaginase and its antigenicity, several L-asparaginase mutants (mL-ASPs) are constructed and expressed. To effectively purify these enzyme mutants for further investigation, a native preparative polyacrylamide gel electrophoresis is developed. The simplicity and reproducibility of this approach permits the purification of different mutants from the crude enzyme extracts, with a sufficient activity to perform immunological and biological studies. Furthermore, the newly developed method is efficient and cost-effective compared with other methods, such as column chromatography and affinity chromatography. As a result, the enzyme mutants with specific activity of 300 approximately 400 U/mg are obtained by the single-step purification with a high degree of purity.

Adsorption and enzyme activity of asparaginase at lipid Langmuir and Langmuir-Blodgett films

International Nuclear Information System (INIS)

Rocha Junior, Carlos da; Caseli, Luciano

2017-01-01

In this present work, the surface activity of the enzyme asparaginase was investigated at the air-water interface, presenting surface activity in high ionic strengths. Asparaginase was incorporated in Langmuir monolayers of the phospholipid dipalmitoylphosphatidylcholine (DPPC), forming a mixed film, which was characterized with surface pressure-area isotherms, surface potential-area isotherms, polarization-modulated infrared reflection-absorption spectroscopy (PM-IRRAS), and Brewster angle microscopy (BAM). The adsorption of the enzyme at the air-water interface condensed the lipid monolayer and increased the film compressibility at high surface pressures. Amide bands in the PM-IRRAS spectra were identified, with the C−N and C =O dipole moments lying parallel to monolayer plane, revealing the structuring of the enzyme into α-helices and β-sheets. The floating monolayers were transferred to solid supports as Langmuir-Blodgett (LB) films and characterized with fluorescence spectroscopy and atomic force microscopy. Catalytic activities of the films were measured and compared to the homogenous medium. The enzyme accommodated in the LB films preserved more than 78% of the enzyme activity after 30 days, in contrast for the homogeneous medium, which preserved less than 13%. The method presented in this work not only allows for an enhanced catalytic activity, but also can help explain why certain film architectures exhibit better performance. - Highlights: • Biomembranes are mimicked with Langmuir monolayers. • Asparaginase is incorporated into the lipid monolayer. • Enzyme adsorption is confirmed with tensiometry and infrared spectroscopy. • Langmuir-Blodgett films of the enzyme present enzyme activity.

Adsorption and enzyme activity of asparaginase at lipid Langmuir and Langmuir-Blodgett films

Energy Technology Data Exchange (ETDEWEB)

Rocha Junior, Carlos da; Caseli, Luciano, E-mail: lcaseli@unifesp.br

2017-04-01

In this present work, the surface activity of the enzyme asparaginase was investigated at the air-water interface, presenting surface activity in high ionic strengths. Asparaginase was incorporated in Langmuir monolayers of the phospholipid dipalmitoylphosphatidylcholine (DPPC), forming a mixed film, which was characterized with surface pressure-area isotherms, surface potential-area isotherms, polarization-modulated infrared reflection-absorption spectroscopy (PM-IRRAS), and Brewster angle microscopy (BAM). The adsorption of the enzyme at the air-water interface condensed the lipid monolayer and increased the film compressibility at high surface pressures. Amide bands in the PM-IRRAS spectra were identified, with the C−N and C =O dipole moments lying parallel to monolayer plane, revealing the structuring of the enzyme into α-helices and β-sheets. The floating monolayers were transferred to solid supports as Langmuir-Blodgett (LB) films and characterized with fluorescence spectroscopy and atomic force microscopy. Catalytic activities of the films were measured and compared to the homogenous medium. The enzyme accommodated in the LB films preserved more than 78% of the enzyme activity after 30 days, in contrast for the homogeneous medium, which preserved less than 13%. The method presented in this work not only allows for an enhanced catalytic activity, but also can help explain why certain film architectures exhibit better performance. - Highlights: • Biomembranes are mimicked with Langmuir monolayers. • Asparaginase is incorporated into the lipid monolayer. • Enzyme adsorption is confirmed with tensiometry and infrared spectroscopy. • Langmuir-Blodgett films of the enzyme present enzyme activity.

Characterization of Three L-Asparaginases from Maritime Pine (Pinus pinaster Ait.).

Science.gov (United States)

Van Kerckhoven, Sonia H; de la Torre, Fernando N; Cañas, Rafael A; Avila, Concepción; Cantón, Francisco R; Cánovas, Francisco M

2017-01-01

Asparaginases (ASPG, EC 3.5.1.1) catalyze the hydrolysis of the amide group of L-asparagine producing L-aspartate and ammonium. Three ASPG, PpASPG1, PpASPG2, and PpASPG3, have been identified in the transcriptome of maritime pine ( Pinus pinaster Ait.) that were transiently expressed in Nicotiana benthamiana by agroinfection. The three recombinant proteins were processed in planta to active enzymes and it was found that all mature forms exhibited double activity asparaginase/isoaspartyl dipeptidase but only PpASPG1 was able to catalyze efficiently L-asparagine hydrolysis. PpASPG1 contains a variable region of 77 amino acids that is critical for proteolytic processing of the precursor and is retained in the mature enzyme. Furthermore, the functional analysis of deletion mutants demonstrated that this protein fragment is required for specific recognition of the substrate and favors enzyme stability. Potassium has a limited effect on the activation of maritime pine ASPG what is consistent with the lack of a critical residue essential for interaction of cation. Taken together, the results presented here highlight the specific features of ASPG from conifers when compared to the enzymes from angiosperms.

Characterization of Three L-Asparaginases from Maritime Pine (Pinus pinaster Ait.

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Sonia H. Van Kerckhoven

2017-06-01

Full Text Available Asparaginases (ASPG, EC 3.5.1.1 catalyze the hydrolysis of the amide group of L-asparagine producing L-aspartate and ammonium. Three ASPG, PpASPG1, PpASPG2, and PpASPG3, have been identified in the transcriptome of maritime pine (Pinus pinaster Ait. that were transiently expressed in Nicotiana benthamiana by agroinfection. The three recombinant proteins were processed in planta to active enzymes and it was found that all mature forms exhibited double activity asparaginase/isoaspartyl dipeptidase but only PpASPG1 was able to catalyze efficiently L-asparagine hydrolysis. PpASPG1 contains a variable region of 77 amino acids that is critical for proteolytic processing of the precursor and is retained in the mature enzyme. Furthermore, the functional analysis of deletion mutants demonstrated that this protein fragment is required for specific recognition of the substrate and favors enzyme stability. Potassium has a limited effect on the activation of maritime pine ASPG what is consistent with the lack of a critical residue essential for interaction of cation. Taken together, the results presented here highlight the specific features of ASPG from conifers when compared to the enzymes from angiosperms.

Asparagine and glycine metabolism in rat liver mitochondria and in mouse L5178Y lymphoma cells resistant or sensitive to the anticancer drug L-asparaginase

Energy Technology Data Exchange (ETDEWEB)

Keefer, J.F. Jr.

1986-01-01

Rat liver mitochondrial asparagine was found to be degraded via an aminotransferase and omega-amidase. Evidence includes oxaloacetate production from asparagine only when glyoxylate was added and production of radiolabeled ..cap alpha..-ketosuccinamate via metabolism of (U-/sup 14/C)asparagine. In the cytosol, asparagine is degraded primarily via asparaginase and subsequent transamination. A new HPLC technique for separation of citric acid cycle intermediates was developed using: ion pairing with 20 mM each to tetrabutylammonium hydroxide and Na/sub 2/SO/sub 4/; pH 7.0; isocratic elution; and detection at 210 nm. Amino acid content of mouse lymphoma cells either sensitive (L5178Y) or resistant (L5178Y/L-ASE) to the anticancer drug L-asparaginase was studied. The concentration of asparagine was 1.5 times higher and the concentrations of the essential amino acids histidine, methionine, valine and phenylalanine were two times higher in asparaginase-resistant than sensitive cells. In vivo but not in vitro studies indicated that glucine decreases in sensitive but not resistant cells upon asparaginase treatment. Asparagine and glycine metabolism was further studied using /sup 14/C radiolabel conversion of asparagine, glyoxylate, glycine and serine. Glycine metabolism is especially important in lymphomas and leukemias because these cells contain higher concentrations of glycine that other cancer and normal cells. Therefore, glycine levels were studied and were found to decrease in sensitive but not resistant cells upon asparaginase administration.

Asparaginase-associated pancreatitis: a study on phenotype and genotype in the NOPHO ALL2008 protocol

DEFF Research Database (Denmark)

Wolthers, B. O.; Frandsen, Thomas L.; Abrahamsson, Jonas

2016-01-01

Asparaginase (ASP)-associated pancreatitis (AAP) occurs during acute lymphoblastic leukemia treatment. Among 1285 children (1.0-17.9 years) diagnosed during July 2008-December 2014 and treated according to the Nordic/Baltic ALL2008 protocol, 86 (cumulative incidence = 6.8%) developed AAP. Seventy...

Minimally-Myelosuppressive Asparaginase-Containing Induction Regimen for Treatment of a Jehovah’s Witness with mutant IDH1/NPM1/NRAS Acute Myeloid Leukemia

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Ashkan Emadi

2016-03-01

Full Text Available Treatment of patients with acute myeloid leukemia (AML who do not wish to accept blood product transfusion, including Jehovah’s Witnesses, is extremely challenging. The use of conventional chemotherapy for induction of complete remission (CR results in profound anemia and thrombocytopenia requiring frequent transfusions of blood products, without which such treatment will be life-threatening. Finding a well tolerable, minimally myelosuppressive induction regimen for such patients with AML is a clear example of area of unmet medical need. Here, we report a successful treatment of a 52-year-old Jehovah’s Witness with newly diagnosed AML with peg-asparaginase, vincristine and methylprednisolone. The AML was characterized with normal karyotype, and mutations in isocitrate dehydrogenase 1 (IDH1-Arg132Ser, nucleophosmin 1 (NPM1-Trp289Cysfs*12 and neuroblastoma RAS viral oncogene homolog (NRAS-G1y12Va1. After one 28-day cycle of treatment, the patient achieved complete remission with incomplete count recovery (CRi and after the second cycle, he achieved CR with full blood count recovery. The patient has never received any blood products. Notwithstanding that myeloperoxidase-induced oxidative degradation of vincristine results in its lack of activity as monotherapy in AML, its combination with corticosteroid and asparaginase has resulted in a robust remission in this patient. Diminished steroid clearance by asparaginase activity as well as reduction in serum glutamine level induced by glutaminase enzymatic activity of asparaginase may have contributed to effective killing of the myeloblasts that carry IDH1/NPM1/NRAS mutations. In conclusion, asparaginase-containing regimens, which are approved for treatment of acute lymphoblastic leukemia (ALL but not AML, can be used to treat patients with AML who do not accept blood transfusion.

L-ASPARAGINASE FROM BACILLUS SP. RKS-20: PROCESS OPTIMIZATION AND APPLICATION IN THE INHIBITION OF ACRYLAMIDE FORMATION IN FRIED FOODS

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Richi V. Mahajan

2014-08-01

Full Text Available Reports of presence of acrylamide in wide range of fried and baked foods, most notably potato chips and French fries, by Swedish researchers in 2002 has raised a worldwide concern. However, the enzyme Lasparaginase reduces the formation of acrylamide in fried foods by pre-amidohydrolase of L-asparagine present. In this context, we report the hyper production of L-asparaginase from Bacillus sp. RKS-20, by process optimization involving statistical modeling approach. A maximum of 15.10 IU/ml of L-asparaginase were obtained in 18h under statistically optimized conditions wherein KH2 PO4 (3.0 g/L, NaCl (1.0 g/L, L-asparagine (14.0 g/L and glucose (2.0 g/L were the influential factors. This was an approximately 10-fold increase as compared to the initial un-optimized activity of 1.50 IU/ml. The potential of this enzyme for the inhibition of acrylamide formation was confirmed when the potato slices treated with L-asparaginase (40 IU/mg of dry potatoes, showed reduction of 69.80% in acrylamide formation upon frying as compared to untreated potato slices. Hence, this enzyme is potential candidate for healthier production of food.

Purification and Characterization of a Novel and Robust L-Asparaginase Having Low-Glutaminase Activity from Bacillus licheniformis: In Vitro Evaluation of Anti-Cancerous Properties

Science.gov (United States)

Mahajan, Richi V.; Kumar, Vinod; Rajendran, Vinoth; Saran, Saurabh; Ghosh, Prahlad C.; Saxena, Rajendra Kumar

2014-01-01

L-asparaginase having low glutaminase has been a key therapeutic agent in the treatment of acute lymphpoblastic leukemia (A.L.L). In the present study, an extracellular L-asparaginase with low glutaminase activity, produced by Bacillus licheniformis was purified to homogeneity. Protein was found to be a homotetramer of 134.8 KDa with monomeric size of 33.7 KDa and very specific for its natural substrate i.e. L-asparagine. The activity of purified L-asparaginase enhanced in presence of cations including Na+ and K+, whereas it was moderately inhibited in the presence of divalent cations and thiol group blocking reagents. The purified enzyme was maximally active over the range of pH 6.0 to 10.0 and temperature of 40°C and enzyme was stable maximum at pH 9.0 and −20°C. CD spectra of L-asparaginase predicted the enzyme to consist of 63.05% α- helix and 3.29% β-sheets in its native form with T222 of 58°C. Fluorescent spectroscopy showed the protein to be stable even in the presence of more than 3 M GdHCl. Kinetic parameters Km, Vmax and kcat of purified enzyme were found as 1.4×10−5 M, 4.03 IU and 2.68×103 s−1, respectively. The purified L-asparaginase had cytotoxic activity against various cancerous cell lines viz. Jurkat clone E6-1, MCF-7 and K-562 with IC50 of 0.22 IU, 0.78 IU and 0.153 IU respectively. However the enzyme had no toxic effect on human erythrocytes and CHO cell lines hence should be considered potential candidate for further pharmaceutical use as an anticancer drug. PMID:24905227

In vivo imaging of antileukemic drug asparaginase reveals a rapid macrophage-mediated clearance from the bone marrow

NARCIS (Netherlands)

Van Der Meer, Laurens T.; Terry, Samantha Y.A.; Van Ingen Schenau, Dorette S.; Andree, Kiki Carlijn; Franssen, Gerben M.; Roeleveld, Debbie M.; Metselaar, Josbert M.; Reinheckel, Thomas; Hoogerbrugge, Peter M.; Boerman, Otto C.; van Leeuwen, Frank N.

2017-01-01

Maxima Center for Pediatric Oncology, Utrecht, The Netherlands The antileukemic drug asparaginase, a key component in the treatment of acute lymphoblastic leukemia, acts by depleting asparagine from the blood. However, little is known about its pharmacokinetics, and mechanisms of therapy resistance

Produção, caracterização bioquímica e aplicação de L-asparaginase fúngica

OpenAIRE

Fernanda Furlan Gonçalves Dias

2016-01-01

Resumo: L-Asparaginases são enzimas que catalisam a hidrólise da L-asparagina a ácido L-aspártico e amônia. As L-asparaginases microbianas têm recebido atenção devido ao seu papel no tratamento da leucemia linfoblástica aguda e devido à sua crescente aplicação na indústria de alimentos visando à redução da formação de acrilamida durante o processamento de alimentos. Um número crescente de pesquisas tem estudado a aplicação dessa enzima em diferentes matrizes alimentares comprovando seus efeit...

Utilization of raw materials from agroindustry – sugar cane juice and yeast extract – for asparaginase production by Zymomonas mobilis CP4/ Uso de matérias primas da agroindústria – garapa e extrato de levedura – na produção de asparaginase por Zymomonas mobilis CP4

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Maria Antonia Pedrine Colabone Celligoi

2007-08-01

Full Text Available Sugar cane juice and yeast extract have been used for asparaginase production by Z. mobilis CP4. A complete factorial design of two variables (yeast extract and asparagin at three levels (1.0; 5.5 and 10.0 g/L with one replication at the central point was used. Batch fermentation utilised sugar cane juice diluted at 8 % (W/V of Total Sugars and an inoculum of 2 mg of cells/mL. After fermentation time of 18 hours, the highest production of asparaginase was 9.75 U/L using both yeast extract (5.5 g/L and asparagin (1.0 g/l.Garapa e extrato de levedura foram usados na produção de asparaginase por Zymomonas mobilis CP4. Na otimização utilizou metodologia de superfície de resposta com 2 variáveis (extrato de levedura e asparagina em 3 níveis (1,0; 5,5 e 10,0 g/L e uma repetição do ponto central. A fermentação em batelada utilizou garapa diluída a 8 % (P/V de Açúcares Totais e inóculo de Zymomonas mobilis CP4 na concentração de 2 mg/mL. Após a fermentação de 18 horas, a maior produção obtida de asparaginase foi de 9,75 U/L em extrato de levedura em 5,5 g/L e asparagina em 1,0 g/L.

Enhanced catalysis of L-asparaginase from Bacillus licheniformis by a rational redesign.

Science.gov (United States)

Sudhir, Ankit P; Agarwaal, Viplove V; Dave, Bhaumik R; Patel, Darshan H; Subramanian, R B

2016-05-01

L-Asparaginase (3.5.1.1) being antineoplastic in nature are used in the treatment of acute lymphoblastic leukemia (ALL). However glutaminase activity is the cause of various side effects when used as a drug against acute lymphoblastic leukemia (ALL). Therefore, there is a need of a novel L-asparaginase (L-ASNase) with low or no glutaminase activity. Such a property has been observed with L-ASNase from B. licheniformis (BliA). The enzyme being glutaminase free in nature paved the way for its improvement to achieve properties similar to or near to the commercially available L-ASNases. Rational enzyme engineering approach resulted in four mutants: G238N, E232A, D103V and Q112H. Among these the mutant enzyme, D103V, had a specific activity of 597.7IU/mg, which is higher than native (rBliA) (407.65IU/mg). Moreover, when the optimum temperature and in vitro half life were studied and compared with native BliA, D103V mutant BliA was better, showing tolerance to higher temperatures and a 3 fold higher half life. Kinetic studies revealed that the mutant D103V L-ASNase has increased substrate affinity, with Km value of 0.42mM and Vmax of 2778.9μmolmin(-1). Copyright © 2016 Elsevier Inc. All rights reserved.

PEG-asparaginase induced severe hypertriglyceridemia.

Science.gov (United States)

Galindo, Rodolfo J; Yoon, Justin; Devoe, Craig; Myers, Alyson K

2016-04-01

Asparaginase (ASP) is an effective chemotherapy agent extensively used in children with acute lymphocytic leukemia (ALL). There has been a recent interest in using ASP in adults with ALL, particularly the less toxic pegylated (PEG) formulation. Hypertriglyceridemia (HTG) is a rare complication of PEG-ASP therapy. We report two cases of obese patients who developed severe HTG after receiving PEG for ALL. Both patients were incidentally found to have severe HTG (TG of 4,330 and 4,420 mg/dL). In both patients, there was no personal or family history of dyslipidemia or hypothyroidism. There was no evidence of pancreatitis or skin manifestations of HTG. Both patients were treated with PEG cessation, low-fat diet and pharmacotherapy. Both patients were re-challenged with PEG, with subsequent increase in TG but no associated complications. TG returned to baseline after discontinuing PEG and while on therapy for HTG. A literature review of PEG-induced HTG in adults demonstrated similar results: asymptomatic presentation despite very severe HTG. HTG is a rare but clinically important adverse effect of PEG. Underlying obesity and/or diabetes may represent risk factors. Clinicians should monitor TG levels during PEG therapy to avoid TG-induced pancreatitis.

L-Asparaginase delivered by Salmonella typhimurium suppresses solid tumors

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Kwangsoo Kim

Full Text Available Bacteria can be engineered to deliver anticancer proteins to tumors via a controlled expression system that maximizes the concentration of the therapeutic agent in the tumor. L-asparaginase (L-ASNase, which primarily converts asparagine to aspartate, is an anticancer protein used to treat acute lymphoblastic leukemia. In this study, Salmonellae were engineered to express L-ASNase selectively within tumor tissues using the inducible araBAD promoter system of Escherichia coli. Antitumor efficacy of the engineered bacteria was demonstrated in vivo in solid malignancies. This result demonstrates the merit of bacteria as cancer drug delivery vehicles to administer cancer-starving proteins such as L-ASNase to be effective selectively within the microenvironment of cancer tissue.

Acrylamide reduction in fried potato slices and strips by using asparaginase in combination with conventional blanching

DEFF Research Database (Denmark)

Pedreschi, Franco; Risum, Jørgen; Granby, Kit

then dried at 85°C for 10 min and immediately partially fried at 175°C for 1min. Finally, frozen par-fried potatoes were fried at 175°C for 3min to obtain French fries. Pre-drying of raw or blanched potato strips did not generate acrylamide formation as expected. Partial frying of pre-dried control potato...... strips generated 370μg/kg of acrylamide and the final frying determined French fries with 2075μg/kg of acrylamide. When control potato strips were treated with a 10000 ASNU/l asparaginase solution at 40°C for 20min, the acrylamide formation in French fries was reduced by 30%. When blanched potato strips...... were treated in the same way, the produced French fries have 60% less acrylamide content than blanched strips without the enzyme treatment. Soaking of blanched potato strips (75°C, 10min) in an 10000 ASNU/l asparaginase solution at 40°C for 20min is an effective way to reduce acrylamide formation after...

Purification, Characterization, and Effect of Thiol Compounds on Activity of the Erwinia carotovora L-Asparaginase

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Suchita C. Warangkar

2010-01-01

Full Text Available L-asparaginase was extracted from Erwinia carotovora and purified by ammonium sulfate fractionation (60–70%, Sephadex G-100, CM cellulose, and DEAE sephadex chromatography. The apparent Mr of enzyme under nondenaturing and denaturing conditions was 150 kDa and 37±0.5 kDa, respectively. L-asparaginase activity was studied in presence of thiols, namely, L-cystine (Cys, L-methionine (Met, N-acetyl cysteine (NAC, and reduced glutathione (GSH. Kinetic parameters in presence of thiols (10–400 M showed an increase in Vmax values (2000, 2223, 2380, 2500, and control 1666.7 moles mg−1min−1 and a decrease in K values (0.086, 0.076, 0.062, 0.055 and control 0.098 mM indicating nonessential mode of activation. KA values displayed propensity to bind thiols. A decrease in Vmax/K ratio in concentration plots showed inverse relationship between free thiol groups (NAC and GSH and bound thiol group (Cys and Met. Enzyme activity was enhanced in presence of thiol protecting reagents like dithiothreitol (DTT, 2-mercaptoethanol (2-ME, and GSH, but inhibited by p-chloromercurybenzoate (PCMB and iodoacetamide (IA.

Suppressed Acrylamide Formation during Baking in Yeast-Leavened Bread Based on added Asparaginase, Baking Time and Temperature Using Response Surface Methodology

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Mashaer Matouri

2018-01-01

Full Text Available  Background and Objective: Acrylamide as a toxic substance for human beings is produced by Maillard reaction at high temperatures. In this research, this reaction can be inhibited based on using aspariganse enzyme, controlling the cooking time and temperature during baking in yeast-leavened bread.Material and Methods: In this study, a response surface methodology 5-level-3-factor central composite design was applied to study the effects of asparaginase (300-900 U Kg-1 of flour, baking temperature (230-280°C and baking time (13-16 min on acrylamide formation in yeast-leavened wheat bread.Results and Conclusion: Added asparaginase showed a reducing effect on acrylamide formation (p≤0.0001. Baking temperature significantly increased the acrylamide content in bread (p≤0.0001. A strong correlation was found between the baking temperature and acrylamide formation. Baking time and its interaction with asparaginase had a low but significant reducing effect on acrylamide content in bread (p≤0.0001. Three parameters of the cooking temperature and time as well as enzyme concentration have been optimized using response surface methodology, their values obtained 245.71°C, 14.55 min and 752.15 U Kg-1, respectively. Enzymatic process could be suggested as a safe and convenient method for preventing acrylamide formation in bread making.Conflict of interest: The authors declare no conflict of interest. 

Proteins from Erwinia asparaginase Erwinase ® and E. coli asparaginase 2 MEDAC ® for treatment of human leukemia, show a multitude of modifications for which the consequences are completely unclear.

Science.gov (United States)

Bae, Narkhyun; Pollak, Arnold; Lubec, Gert

2011-07-01

L-Asparaginase from Erwinia chrysanthemi (ASPG_ERWCH; UniProtKB accession number P06608 (Erwinase(®))) and L-asparaginase 2 from Escherichia coli (ASPG2_ECOLI; UniProtKB accession number P00805 (Medac(®))), both L-asparagine amidohydrolases, are widely used for the treatment of acute lymphoblastic leukemia. A series of serious side effects have been reported and this warrants studies into the protein chemistry of the medical products sold. Mass spectrometry (MS) data on ASPG_ERWCH and ASPG2_ECOLI have not been published so far and herein a gel-based proteomics study was performed to provide information about sequence and modifications of the commercially available medical products. ASPG_ERWCH and ASPG2_ECOLI were applied onto two-dimensional gel electrophoresis, spots were in-gel digested with several proteases and resulting peptides and protein modifications were analysed by nano-ESI-LC-MS/MS. Four spots were observed for ASPG_ERWCH, six spots were observed for ASPG2_ECOLI and the identified proteins showed high sequence coverage without sequence conflicts. Several protein modifications including technical and posttranslational modifications were demonstrated. Protein modifications are known to change physicochemical, immunochemical, biological and pharmacological properties and results from this work may challenge re-designing of the product including possible removal of the modifications by the manufacturer because it is not known whether they are contributing to the serious adverse effects of the protein drug. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

L-Asparaginase Isolated from Phaseolus vulgaris Seeds Exhibited Potent Anti-Acute Lymphoblastic Leukemia Effects In-Vitro and Low Immunogenic Properties In-Vivo

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Saleh A. Mohamed

2016-10-01

Full Text Available Escherichia coli-derived L-asparaginases have been used in the treatment of acute lymphoblastic leukemia (ALL, however, clinical hypersensitivity reactions and silent inactivation due to antibodies against E. coli-asparaginase, lead to inactivation of these preparations in most cases.Therefore, this study was aimed to investigate the cytotoxicity and antitumor effects ofa novel L-asparaginaseenzyme, isolated from Phaseolus vulgaris seeds (P-Asp on the ALL cell line (Jurkat. The immunogenicity of the enzyme was also evaluated in-vivo and results were compared to commercially available enzymes of microbial sources. The data demonstrated that P-Asp has an enhanced anti-proliferative effect on ALL cells as detected by the WST-8 cell viability assay kit. Cells treated with P-Asp also exhibited a higher degree of early apoptosis compared with asparaginase from Escherichia coli (L-Asp or its pegylated form Pegasparagas (PEG-ASP that induced higher rates of late apoptosis and necrosis as detected by an Annexin V/Propidium iodide binding assay. In-vivo experiments indicated that mice treated with P-Asp had less distinct allergenic responses than other bacterial enzyme preparations as indicated by lower serum concentrations of IgG, IgE, IgM and mMCP-1 compared with other treated groups. In conclusion, P-Asp can be considered as a promising candidate for use in the treatment of ALL.

Immobilization of l-Asparaginase on Carrier Materials: A Comprehensive Review.

Science.gov (United States)

Ulu, Ahmet; Ates, Burhan

2017-06-21

There are two major applications of l-asparaginase (L-ASNase): leukemia therapy and the food industry. Especially, its chemotherapeutic effect has attracted interest from the scientific community and individual scientists. Therefore, to protect the intrinsic activity and half-time of L-ASNase, several carriers and immobilization techniques for immobilization of L-ASNase have been described in articles. Unfortunately, a comprehensive review about immobilization of L-ASNase has not been written until now. In this review, we have thoroughly discussed the carriers for L-ASNase by illustrating immobilization findings including both past and present applications. In addition, we have revealed advantages and disadvantages of immobilized enzyme and related it to free form. We believe that this review will not only provide background information, but also guide future developments.

Optimization of Culture Conditions for Production of the Anti-Leukemic Glutaminase Free L-Asparaginase by Newly Isolated Streptomyces olivaceus NEAE-119 Using Response Surface Methodology

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Noura El-Ahmady El-Naggar

2015-01-01

Full Text Available Among the antitumor drugs, bacterial enzyme L-asparaginase has been employed as the most effective chemotherapeutic agent in pediatric oncotherapy especially for acute lymphoblastic leukemia. Glutaminase free L-asparaginase producing actinomycetes were isolated from soil samples collected from Egypt. Among them, a potential culture, strain NEAE-119, was selected and identified on the basis of morphological, cultural, physiological, and biochemical properties together with 16S rRNA sequence as Streptomyces olivaceus NEAE-119 and sequencing product (1509 bp was deposited in the GenBank database under accession number KJ200342. The optimization of different process parameters for L-asparaginase production by Streptomyces olivaceus NEAE-119 using Plackett-Burman experimental design and response surface methodology was carried out. Fifteen variables (temperature, pH, incubation time, inoculum size, inoculum age, agitation speed, dextrose, starch, L-asparagine, KNO3, yeast extract, K2HPO4, MgSO4·7H2O, NaCl, and FeSO4·7H2O were screened using Plackett-Burman experimental design. The most positive significant independent variables affecting enzyme production (temperature, inoculum age, and agitation speed were further optimized by the face-centered central composite design-response surface methodology.

Glycerol-Induced Aggregation of the Oligomeric L-Asparaginase II from E. coli Monitored with ATR-FTIR

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Koba Adeishvili

2001-06-01

Full Text Available Abstract: In this paper attenuated total reflectance Fourier transform infrared spectroscopy has been employed for the study of the structural composition of aggregates of the oligomeric L-asparaginase II from E.coli formed in the presence of glycerol after the induction of refolding of the protein. Apart from the perfect coincidence of the secondary structure composition of EcA2 as determined by FTIR and crystallography [1], it has also been shown that secondary structure of protein in asparaginase deposits is similar to that of the native conformation: 20.7% extended, 22.3% disordered, 31.4% helix and 25.6% turn/bend/β sheet. Certain structural similarities in the range of experimental error was observed for all three protein deposits presented in this paper, indicating a common structural basis for the composition of this types of aggregates. It is concluded that in the constitution of such precipitates, a partially folded (molten globule like state(s is involved, and its stabilisation is a key factor leading to the aggregation. The results presented in this paper might serve to be a good explanation and an excellent basis for the fundamental theory of protein (oligomers precipitation by osmotic substances.

Optimization of Growth Conditions for Purification and Production of L-Asparaginase by Spirulina maxima

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El Baroty, Gamal S.

2016-01-01

L-asparaginase (L-AsnA) is widely distributed among microorganisms and has important applications in medicine and in food technology sectors. Therefore, the ability of the production, purification, and characterization of AsnA from Spirulina maxima (SM) were tested. SM cultures grown in Zarrouk medium containing different N2 (in NaNO3 form) concentrations (1.25, 2.50, and 5.0 g/L) for 18 days contained a significant various quantity of dry biomass yields and AsnA enzyme levels. MS L-AsnA activity was found to be directly proportional to the N2 concentration. The cultures of SM at large scales (300 L medium, 5 g/L N2) showed a high AsnA enzyme activity (898 IU), total protein (405 mg/g), specific enzyme activity (2.21 IU/mg protein), and enzyme yield (51.28 IU/L) compared with those in low N2 cultures. The partial purification of crude MS AsnA enzyme achieved by 80% ammonium sulfate AS precipitated and CM-Sephadex C-200 gel filtration led to increases in the purification of enzyme with 5.28 and 10.91 times as great as that in SM crude enzymes. Optimum pH and temperature of purified AsnA for the hydrolyzate were 8.5 and 37 ± 0.2°C, respectively. To the best of our knowledge, this is the first report on L-asparaginase production in S. maxima. PMID:27525017

Optimization of Growth Conditions for Purification and Production of L-Asparaginase by Spirulina maxima

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Hanaa H. Abd El Baky

2016-01-01

Full Text Available L-asparaginase (L-AsnA is widely distributed among microorganisms and has important applications in medicine and in food technology sectors. Therefore, the ability of the production, purification, and characterization of AsnA from Spirulina maxima (SM were tested. SM cultures grown in Zarrouk medium containing different N2 (in NaNO3 form concentrations (1.25, 2.50, and 5.0 g/L for 18 days contained a significant various quantity of dry biomass yields and AsnA enzyme levels. MS L-AsnA activity was found to be directly proportional to the N2 concentration. The cultures of SM at large scales (300 L medium, 5 g/L N2 showed a high AsnA enzyme activity (898 IU, total protein (405 mg/g, specific enzyme activity (2.21 IU/mg protein, and enzyme yield (51.28 IU/L compared with those in low N2 cultures. The partial purification of crude MS AsnA enzyme achieved by 80% ammonium sulfate AS precipitated and CM-Sephadex C-200 gel filtration led to increases in the purification of enzyme with 5.28 and 10.91 times as great as that in SM crude enzymes. Optimum pH and temperature of purified AsnA for the hydrolyzate were 8.5 and 37 ± 0.2°C, respectively. To the best of our knowledge, this is the first report on L-asparaginase production in S. maxima.

L-Asparaginase of Leishmania donovani: Metabolic target and its role in Amphotericin B resistance

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Jasdeep Singh

2017-12-01

Full Text Available Emergence of Amphotericin B (AmB resistant Leishmania donovani has posed major therapeutic challenge against the parasite. Consequently, combination therapy aimed at multiple molecular targets, based on proteome wise network analysis has been recommended. In this regard we had earlier identified and proposed L-asparaginase of Leishmania donovani (LdAI as a crucial metabolic target. Here we report that both LdAI overexpressing axenic amastigote and promastigote forms of L. donovani survives better when challenged with AmB as compared to wild type strain. Conversely, qRT-PCR analysis showed an upregulation of LdAI in both forms upon AmB treatment. Our data demonstrates the importance of LdAI in imparting immediate protective response to the parasite upon AmB treatment. In the absence of structural and functional information, we modeled LdAI and validated its solution structure through small angle X-ray scattering (SAXS analysis. We identified its specific inhibitors through ligand and structure-based approach and characterized their effects on enzymatic properties (Km, Vmax, Kcat of LdAI. We show that in presence of two of the inhibitors L1 and L2, the survival of L. donovani is compromised whereas overexpression of LdAI in these cells restores viability. Taken together, our results conclusively prove that LdAI is a crucial metabolic enzyme conferring early counter measure against AmB treatment by Leishmania. Keywords: Leishmania donovani, L-asparaginase, Amphotericin B resistance, Metabolic target

Up-regulation of asparagine synthetase expression is not linked to the clinical response to L-asparaginase in pediatric acute lymphoblastic leukemia

NARCIS (Netherlands)

I.M. Appel (Inge); M.L. den Boer (Monique); J.P.P. Meijerink (Jules); A.J.P. Veerman (Anjo); N.C.M. Reniers (N. C M); R. Pieters (Rob)

2006-01-01

textabstractL-asparaginase (L-Asp) is an effective drug for treatment of children with acute lymphoblastic leukemia (ALL). The effectiveness is generally thought to result from a rapid depletion of asparagine in serum and cells. Asparagine synthetase (AS) opposes the action of L-Asp by resynthesis

Asparaginase-associated concurrence of hyperlipidemia, hyperglobulinemia, and thrombocytosis was successfully treated by centrifuge/membrane hybrid double-filtration plasmapheresis.

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Wang, Taina; Xu, Bin; Fan, Rong; Liu, Zhihong; Gong, Dehua

2016-01-01

Asparaginase-associated concurrence of hyperlipidemia, hyperglobulinemia, and thrombocytosis is a rare complication requiring aggressive lipoprotein apheresis, but no one of currently available lipoprotein apheresis methods can simultaneously resolve the 3 abnormalities. Herein, we reported a construction of double-filtration plasmapheresis (DFPP) using a combination of centrifugal/membranous plasma separation techniques to successfully treat a patient with hyperlipidemia, hyperglobulinemia, and thrombocytosis. A male presented with severe hyperlipidemia, hyperglobulinemia, and thrombocytosis during asparaginase treatment for NK/T-cell lymphoblastic lymphoma and was scheduled to receive lipoprotein apheresis. To simultaneously remove lipoproteins, immunoglobulin, and deplete platelets from blood, a centrifuge/membrane hybrid DFPP was constructed as following steps: plasma and part of platelets were separated first from whole blood by centrifugal technique and then divided by a fraction plasma separator into 2 parts: platelets and plasma components with large size, which were discarded; and those containing albumin, which were returned to blood with a supplement of extrinsic albumin solution. DFPP lasted 240 minutes uneventfully, processing 5450-mL plasma. The concentrations of plasma components before DFPP were as follows: triglycerides 38.22 mmol/L, total cholesterols 22.98 mmol/L, immunoglobulin A (IgA) 15.7 g/L, IgG 12.7 g/L, and IgM 14.3 g/L; whereas after treatment were 5.69 mmol/L, 2.38 mmol/L, 2.5 g/L, 7.7 g/L, and 0.4 g/L, respectively. The respective reduction ratio was 85.1%, 89.6%, 83.9%, 39.4%, and 96.9%. Platelet count decreased by 40.4% (from 612 × 10(9)/L to 365 × 10(9)/L). Centrifuge/membrane hybrid DFPP can simultaneously remove lipoproteins, immunoglobulin, and deplete platelets, with a success in treatment of asparaginase treatment-induced hyperlipidemia, hyperglobulinemia, and thrombocytosis, and may be useful for patients

[Binding of the antileukemia drug Escherichia coli L-asparaginase to the plasma membrane of normal human mononuclear cells].

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Mercado-Vianco, L; Arenas-Díaz, G

1999-06-01

To demonstrate that the enzyme L-asparaginase from Escherichia coli (EcA) binds to the plasma membranes of normal human lymphocytes and monocytes. Lymphocytes and monocytes were isolated from heparinized blood samples which came from healthy volunteer donors. The cells were incubated with EcA to detect a possible binding of the enzyme to the mononuclear cells by indirect immunofluorescence using confocal microscopy. Meanwhile, ultracentrifugation was used to obtain the erythrocyte ghost microsomal fraction (P100) which was then analyzed by Western blotting to determine if EcA binds the lipid bilayer unspecifically. For the immunoassays, monospecific polyclonal antibodies were obtained from ascitic tumors developed in mice immunized with commercial L-asparaginase. EcA bins the lymphocyte and monocyte plasma membranes. In monocytes, there occurs a capping phenomenon, that is, the accumulation of fluorescent marker in one region. The image analyzer highlights it clearly at a depth of 3.8 microns. This binding would be unspecific, that is, there is no mediation of a specific receptor that binds EcA. This arises from the ability of the enzyme to bind to the membranes of erythrocyte ghost, as evidenced by the ability of the molecule to associate with a hydrophobic medium. The antibodies against EcA obtained from ascitic tumours developed in mice do not show cross reactivity with Na+/K+ ATPase, aspartate aminotransferase, nor with extracts of blood cells, which would make it a specific tool for the detection of EcA in whole cells and in homogenates electrotransfered to nitrocellulose membranes. L-asparaginase from E. coli behaves as a lipoprotein due to its ability to insert itself into hydrophobic environments, in which it resembles an isozyme present in T. pyriformis. The binding of this enzyme to lymphocytes and monocytes, demonstrated in this work, would permit the modification of the antileukemic treatment injecting doses of EcA bound to patient's own isolated immune

The K⁺ dependent asparaginase, NSE₁, is crucial for plant growth and seed production in Lotus japonicus

DEFF Research Database (Denmark)

Credali, Alfredo; Garcia-Calderón, Margarita; Dam, Svend Secher

2013-01-01

The physiological role of K+-dependent and K+-independent asparaginases in plants remains unclear, and the contribution from individual isoforms during development is poorly understood. We have used reverse genetics to assess the phenotypes produced by the deficiency of K+-dependent NSE1 asparagi...

Pharmacokinetics, pharmacodynamics, efficacy, and safety of a new recombinant asparaginase preparation in children with previously untreated acute lymphoblastic leukemia: A randomized phase 2 clinical trial

NARCIS (Netherlands)

R. Pieters (Rob); I.M. Appel (Inge); H.J. Kuehnel; I. Tetzlaff-Fohr (Iris); U. Pichlmeier (Uwe); I. van der Vaart (Inekee); E. Visser (Eline); R.L. Stigter

2008-01-01

textabstractThe pharmacokinetics, pharmacodynam-ics, efficacy, and safety of a new recom-binant Escherichia coli - asparaginase preparation was compared withAsparagi-nase medac. Thirty-two children with acute lymphoblastic leukemia were randomized to receive one of both agents at a dose of 5000

[Update on L-asparaginase treatment in paediatrics].

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Moscardó Guilleme, C; Fernández Delgado, R; Sevilla Navarro, J; Astigarraga Aguirre, I; Rives Solà, S; Sánchez de Toledo Codina, J; Fuster Soler, J L; Parra Ramirez, L; Molina Garicaño, J; González Martínez, B; Madero López, L

2013-11-01

L-asparaginase (L-ASP) is one of the cornerstones of the treatment of acute lymphoblastic leukemia and non-Hodgkin lymphoma. It is an enzyme of bacterial origin capable of transforming L-asparagine to aspartic acid. The extracellular depletion of L-asparagine inhibits protein synthesis in lymphoblasts, inducing their apoptosis. Numerous studies have demonstrated that treatment with L-ASP improves survival of patients, but there are clear differences in the characteristics of the three currently available formulations. This article reviews the dosage, activity and side effects of the two L-ASP derived from Escherichia coli (native and pegylated), and the one derived from Erwinia chrysanthemi (Erwinia ASP). Despite its indisputable indication over the past50 years, there are still many points of contention, and its use is still marked by the side effects of the inhibition of protein synthesis. The short half-life of native forms, and the most frequently used parenteral administration by intramuscular injections, affects the quality of life of the patients. Therefore, recent studies claim to evaluate alternatives, such as the formulation of longer half-life pegylated L-ASP, and the use of intravenous formulations. There are encouraging results to date with both preparations. Still, further studies are needed to establish which should be the formulation and frontline indicated route of administration, optimal dosing, and management of adverse effects. Copyright © 2013 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

Radiotherapy is essential after complete response to asparaginase-containing chemotherapy in early-stage extranodal nasal-type NK/T-cell lymphoma: A multicenter study from the China Lymphoma Collaborative Group (CLCG).

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Deng, Xiu-Wen; Wu, Jun-Xin; Wu, Tao; Zhu, Su-Yu; Shi, Mei; Su, Hang; Wang, Ying; He, Xia; Xu, Li-Ming; Yuan, Zhi-Yong; Zhang, Li-Ling; Wu, Gang; Qu, Bao-Lin; Qian, Li-Ting; Hou, Xiao-Rong; Zhang, Fu-Quan; Zhang, Yu-Jing; Zhu, Yuan; Cao, Jian-Zhong; Lan, Sheng-Min; Dong, Mei; Qi, Shu-Nan; Yang, Yong; Li, Ye-Xiong

2018-05-05

This study aimed to clarify the benefit of radiotherapy (RT) in patients with early-stage extranodal NK/T-cell lymphoma (NKTCL) who achieve a complete response (CR) after asparaginase-containing chemotherapy (CT). Of 240 patients achieved a CR after asparaginase-containing CT, 202 patients received additional RT (CT + RT), and 38 patients did not (CT alone). Compared to CT alone, CT + RT significantly improved overall survival (OS), disease-free survival (DFS) and locoregional control (LRC). The 5-year OS, DFS and LRC rates were 84.9%, 76.2% and 84.9% for CT + RT, compared to 58.9% (P = 0.006), 43.6% (P = 0.001) and 62.1% (P = 0.026) for CT alone. The 5-year cumulative disease recurrence rate was 18.8% for CT + RT compared to 46.9% (P = 0.003) for CT alone. High-dose RT (≥50 Gy) significantly decreased the risk of locoregional recurrence. The 5-year cumulative locoregional failure rate was 35.5% for patients receiving <50 Gy compared to 8.8% for patients receiving ≥50 Gy (P = 0.028). For patients with early-stage NKTCL who achieve a CR after asparaginase-containing CT, omission of RT results in frequent locoregional recurrence and a poor prognosis; RT is essential to improve locoregional control and survival. Copyright © 2018 Elsevier B.V. All rights reserved.

Identification and structural analysis of an L-asparaginase enzyme from guinea pig with putative tumor cell killing properties.

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Schalk, Amanda M; Nguyen, Hien-Anh; Rigouin, Coraline; Lavie, Arnon

2014-11-28

The initial observation that guinea pig serum kills lymphoma cells marks the serendipitous discovery of a new class of anti-cancer agents. The serum cell killing factor was shown to be an enzyme with L-asparaginase (ASNase) activity. As a direct result of this observation, several bacterial L-asparaginases were developed and are currently approved by the Food and Drug Administration for the treatment of the subset of hematological malignancies that are dependent on the extracellular pool of the amino acid asparagine. As drugs, these enzymes act to hydrolyze asparagine to aspartate, thereby starving the cancer cells of this amino acid. Prior to the work presented here, the precise identity of this guinea pig enzyme has not been reported in the peer-reviewed literature. We discovered that the guinea pig enzyme annotated as H0W0T5_CAVPO, which we refer to as gpASNase1, has the required low Km property consistent with that possessed by the cell-killing guinea pig serum enzyme. Elucidation of the ligand-free and aspartate complex gpASNase1 crystal structures allows a direct comparison with the bacterial enzymes and serves to explain the lack of L-glutaminase activity in the guinea pig enzyme. The structures were also used to generate a homology model for the human homolog hASNase1 and to help explain its vastly different kinetic properties compared with gpASNase1, despite a 70% sequence identity. Given that the bacterial enzymes frequently present immunogenic and other toxic side effects, this work suggests that gpASNase1 could be a promising alternative to these bacterial enzymes. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

Iatrogenic Coagulopathy and the Development of Posterior Reversible Encephalopathy Syndrome after L-asparaginase Chemotherapy

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Eugenia Rota

2016-01-01

Full Text Available Posterior reversible encephalopathy syndrome (PRES is a clinical and radiological syndrome mostly related to hypertension, eclampsia, renal failure, or to chemotherapy and/or immunosuppressive drugs. Although the PRES pathophysiology is multifactorial, hypertension and endothelial dysfunction are hypothesized to be the pivotal factors. Here we report a case of PRES in an adult patient after chemotherapy (Escherichia coli L-asparaginase [L-ASP], daunorubicin, vincristine, and intrathecal methotrexate for acute lymphoblastic leukemia. The development of the PRES was strictly associated with an iatrogenic coagulopathy induced by L-ASP, which inhibits the biosynthesis of hepatic coagulation factors. The nadir of platelet count, antithrombin III (ATIII and fibrinogen curve was coincident with the onset of the PRES neurological picture; subsequently, the normalization of the ATIII and fibrinogen levels seemed to parallel the good clinical evolution. This case seems to provide new insights into the PRES pathophysiological mechanisms.

Produção de L-asparaginase por Zymomonas mobilis durante a fermentação do melaço: otimização das condições de cultivo utilizando delineamento fatorial - DOI: 10.4025/actascitechnol.v28i2.1178

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Doumit Camilios Neto

2006-03-01

Full Text Available A L-asparaginase é uma enzima com atividade anti-leucêmica produzida por microrganismos, principalmente bactérias gram-negativas. Zymomonas mobilis é uma bactéria gram-negativa, que apresenta potencial para produção de L-asparaginase. Esse estudo buscou a otimização da produção de L-asparaginase por Zymomonas mobilis, durante a fermentação do melaço de cana-de-açúcar, utilizando um delineamento fatorial incompleto 33. O modelo obtido através da metodologia de superfície de resposta foi otimizado pelo software Otplex. Obteve-se bom ajuste do modelo aos dados experimentais, sendo o coeficiente de determinação total (R2, 95%. A máxima atividade enzimática (16,55 UI L-1 foi obtida com uma concentração de açúcares redutores totais no melaço de 100,0 g L-1, 2,0 g L-1 de extrato de levedura e com 21 horas de fermentação. A validação experimental confirmou a capacidade preditiva do modelo, sendo a diferença entre resposta estimada(Ŷ1 e resposta observada (Y1 apenas de 1%.

Minimal contribution of severe hypertriglyceridemia in L-asparaginase-associated pancreatitis developed in a child with acute lymphocytic leukemia.

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Goto, Yoshinori; Nishimura, Ryosei; Nohara, Atsushi; Mase, Shintaro; Fujiki, Toshihiro; Irabu, Hitoshi; Kuroda, Rie; Araki, Raita; Ikawa, Yasuhiro; Maeba, Hideaki; Yachie, Akihiro

2016-08-01

A 10-year-old girl developed L-asparaginase (ASP)-associated pancreatitis during chemotherapy for acute lymphocytic leukemia. Her symptoms showed alleviation with continuous regional arterial infusion of protease inhibitor and systemic somatostatin analog therapy. She had intermittent and marked hypertriglyceridemia, an initial trigger for pancreatitis, probably as a side effect of ASP and steroids. However, we considered the pancreatitis to have developed mainly because of factors other than hypertriglyceridemia as lipoprotein analysis confirmed chylomicron levels to be nearly undetectable. Extremely large chylomicrons contribute directly to the onset of pancreatitis by causing blockage of small vessels. Although it is necessary to examine patients for dyslipidemia developing as a side effect of ASP, therapeutic intervention for hypertriglyceridemia is not considered to prevent the onset of ASP-associated pancreatitis.

Domains of Pyrococcus furiosus L-asparaginase fold sequentially and assemble through strong intersubunit associative forces.

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Garg, Dushyant K; Tomar, Rachana; Dhoke, Reema R; Srivastava, Ankit; Kundu, Bishwajit

2015-05-01

Here, we report the folding and assembly of a Pyrococcus furiosus-derived protein, L-asparaginase (PfA). PfA functions as a homodimer, with each monomer made of distinct N- and C-terminal domains. The purified individual domains as well as single Trp mutant of each domain were subjected to chemical denaturation/renaturation and probed by combination of spectroscopic, chromatographic, quenching and scattering techniques. We found that the N-domain acts like a folding scaffold and assists the folding of remaining polypeptide. The domains displayed sequential folding with the N-domain having higher thermodynamic stability. We report that the extreme thermal stability of PfA is due to the presence of high intersubunit associative forces supported by extensive H-bonding and ionic interactions network. Our results proved that folding cooperativity in a thermophilic, multisubunit protein is dictated by concomitant folding and association of constituent domains directly into a native quaternary structure. This report gives an account of the factors responsible for folding and stability of a therapeutically and industrially important protein.

Design of starch functionalized biodegradable P(MAA-co-MMA) as carrier matrix for l-asparaginase immobilization.

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Ulu, Ahmet; Koytepe, Suleyman; Ates, Burhan

2016-11-20

We prepared biodegradable P(MAA-co-MMA)-starch composite as carrier matrix for the immobilization of l-asparaginase (l-ASNase), an important chemotherapeutic agent in acute lymphoblastic leukemia. Chemical characteristics and thermal stability of the prepared composites were determined by FT-IR, TGA, DTA and, DSC, respectively. Also, biodegradability measurements of P(MAA-co-MMA)-starch composites were carried out to examine the effects of degradation of the starch. Then, l-ASNase was immobilized on the P(MAA-co-MMA)-starch composites. The surface morphology of the composite before and after immobilization was characterized by SEM, EDX, and AFM. The properties of the immobilized l-ASNase were investigated and compared with the free enzyme. The immobilized l-ASNase had better showed thermal and pH stability, and remained stable after 30days of storage at 25°C. Thus, based on the findings of the present work, the P(MAA-co-MMA)-starch composite can be exploited as the biocompatible matrix used for l-ASNase immobilization for medical applications due to biocompatibility and biodegradability. Copyright © 2016 Elsevier Ltd. All rights reserved.

Asparaginase treatment side-effects may be due to genes with homopolymeric Asn codons (Review-Hypothesis)

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BANERJI, JULIAN

2015-01-01

The present treatment of childhood T-cell leukemias involves the systemic administration of prokary-otic L-asparaginase (ASNase), which depletes plasma Asparagine (Asn) and inhibits protein synthesis. The mechanism of therapeutic action of ASNase is poorly understood, as are the etiologies of the side-effects incurred by treatment. Protein expression from genes bearing Asn homopolymeric coding regions (N-hCR) may be particularly susceptible to Asn level fluctuation. In mammals, N-hCR are rare, short and conserved. In humans, misfunctions of genes encoding N-hCR are associated with a cluster of disorders that mimic ASNase therapy side-effects which include impaired glycemic control, dislipidemia, pancreatitis, compromised vascular integrity, and neurological dysfunction. This paper proposes that dysregulation of Asn homeostasis, potentially even by ASNase produced by the microbiome, may contribute to several clinically important syndromes by altering expression of N-hCR bearing genes. By altering amino acid abundance and modulating ribosome translocation rates at codon repeats, the microbiomic environment may contribute to genome decoding and to shaping the proteome. We suggest that impaired translation at poly Asn codons elevates diabetes risk and severity. PMID:26178806

Asparaginase treatment side-effects may be due to genes with homopolymeric Asn codons (Review-Hypothesis).

Science.gov (United States)

Banerji, Julian

2015-09-01

The present treatment of childhood T-cell leukemias involves the systemic administration of prokaryotic L-asparaginase (ASNase), which depletes plasma Asparagine (Asn) and inhibits protein synthesis. The mechanism of therapeutic action of ASNase is poorly understood, as are the etiologies of the side-effects incurred by treatment. Protein expression from genes bearing Asn homopolymeric coding regions (N-hCR) may be particularly susceptible to Asn level fluctuation. In mammals, N-hCR are rare, short and conserved. In humans, misfunctions of genes encoding N-hCR are associated with a cluster of disorders that mimic ASNase therapy side-effects which include impaired glycemic control, dislipidemia, pancreatitis, compromised vascular integrity, and neurological dysfunction. This paper proposes that dysregulation of Asn homeostasis, potentially even by ASNase produced by the microbiome, may contribute to several clinically important syndromes by altering expression of N-hCR bearing genes. By altering amino acid abundance and modulating ribosome translocation rates at codon repeats, the microbiomic environment may contribute to genome decoding and to shaping the proteome. We suggest that impaired translation at poly Asn codons elevates diabetes risk and severity.

Comparison of three rapamycin dosing schedules in A/J Tsc2+/- mice and improved survival with angiogenesis inhibitor or asparaginase treatment in mice with subcutaneous tuberous sclerosis related tumors

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Dabora Sandra L

2010-02-01

Full Text Available Abstract Background Tuberous Sclerosis Complex (TSC is an autosomal dominant tumor disorder characterized by the growth of hamartomas in various organs including the kidney, brain, skin, lungs, and heart. Rapamycin has been shown to reduce the size of kidney angiomyolipomas associated with TSC; however, tumor regression is incomplete and kidney angiomyolipomas regrow after cessation of treatment. Mouse models of TSC2 related tumors are useful for evaluating new approaches to drug therapy for TSC. Methods In cohorts of Tsc2+/- mice, we compared kidney cystadenoma severity in A/J and C57BL/6 mouse strains at both 9 and 12 months of age. We also investigated age related kidney tumor progression and compared three different rapamycin treatment schedules in cohorts of A/J Tsc2+/- mice. In addition, we used nude mice bearing Tsc2-/- subcutaneous tumors to evaluate the therapeutic utility of sunitinib, bevacizumab, vincristine, and asparaginase. Results TSC related kidney disease severity is 5-10 fold higher in A/J Tsc2+/- mice compared with C57BL/6 Tsc2+/- mice. Similar to kidney angiomyolipomas associated with TSC, the severity of kidney cystadenomas increases with age in A/J Tsc2+/- mice. When rapamycin dosing schedules were compared in A/J Tsc2+/- cohorts, we observed a 66% reduction in kidney tumor burden in mice treated daily for 4 weeks, an 82% reduction in mice treated daily for 4 weeks followed by weekly for 8 weeks, and an 81% reduction in mice treated weekly for 12 weeks. In the Tsc2-/- subcutaneous tumor mouse model, vincristine is not effective, but angiogenesis inhibitors (sunitinib and bevacizumab and asparaginase are effective as single agents. However, these drugs are not as effective as rapamycin in that they increased median survival only by 24-27%, while rapamycin increased median survival by 173%. Conclusions Our results indicate that the A/J Tsc2+/- mouse model is an improved, higher through-put mouse model for future TSC

Therapeutic Drug Monitoring of Asparaginase Activity-Method Comparison of MAAT and AHA Test Used in the International AIEOP-BFM ALL 2009 Trial.

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Lanvers-Kaminsky, Claudia; Rüffer, Andrea; Würthwein, Gudrun; Gerss, Joachim; Zucchetti, Massimo; Ballerini, Andrea; Attarbaschi, Andishe; Smisek, Petr; Nath, Christa; Lee, Samiuela; Elitzur, Sara; Zimmermann, Martin; Möricke, Anja; Schrappe, Martin; Rizzari, Carmelo; Boos, Joachim

2018-02-01

In the international AIEOP-BFM ALL 2009 trial, asparaginase (ASE) activity was monitored after each dose of pegylated Escherichia coli ASE (PEG-ASE). Two methods were used: the aspartic acid β-hydroxamate (AHA) test and medac asparaginase activity test (MAAT). As the latter method overestimates PEG-ASE activity because it calibrates using E. coli ASE, method comparison was performed using samples from the AIEOP-BFM ALL 2009 trial. PEG-ASE activities were determined using MAAT and AHA test in 2 sets of samples (first set: 630 samples and second set: 91 samples). Bland-Altman analysis was performed on ratios between MAAT and AHA tests. The mean difference between both methods, limits of agreement, and 95% confidence intervals were calculated and compared for all samples and samples grouped according to the calibration ranges of the MAAT and the AHA test. PEG-ASE activity determined using the MAAT was significantly higher than when determined using the AHA test (P Wilcoxon signed-rank test). Within the calibration range of the MAAT (30-600 U/L), PEG-ASE activities determined using the MAAT were on average 23% higher than PEG-ASE activities determined using the AHA test. This complies with the mean difference reported in the MAAT manual. With PEG-ASE activities >600 U/L, the discrepancies between MAAT and AHA test increased. Above the calibration range of the MAAT (>600 U/L) and the AHA test (>1000 U/L), a mean difference of 42% was determined. Because more than 70% of samples had PEG-ASE activities >600 U/L and required additional sample dilution, an overall mean difference of 37% was calculated for all samples (37% for the first and 34% for the second set). Comparison of the MAAT and AHA test for PEG-ASE activity confirmed a mean difference of 23% between MAAT and AHA test for PEG-ASE activities between 30 and 600 U/L. The discrepancy increased in samples with >600 U/L PEG-ASE activity, which will be especially relevant when evaluating high PEG-ASE activities in

Characterization of L-asparaginase from marine-derived Aspergillus niger AKV-MKBU, its antiproliferative activity and bench scale production using industrial waste.

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Vala, Anjana K; Sachaniya, Bhumi; Dudhagara, Dushyant; Panseriya, Haresh Z; Gosai, Haren; Rawal, Rakesh; Dave, Bharti P

2018-03-01

L-asparaginase (LA), an enzyme with anticancer activities, produced by marine-derived Aspergillus niger was subjected to purification and characterization. The purified enzyme was observed to have molecular weight ∼90KDa. The enzyme retained activity over a wide range of pH, i.e. pH 4-10. The enzyme was quite stable in temperature range 20-40°C. Tween 80 and Triton X-100 were observed to enhance LA activity while inhibition of LA activity was observed in presence of heavy metals. The values for K m was found to be 0.8141 mM and V max was 6.228μM/mg/min. The enzyme exhibited noteworthy antiproliferative activity against various cancer cell lines tested. Successful bench scale production (in 5L bioreacator) of LA using groundnut oil cake as low cost substrate has also been carried out. Copyright © 2017 Elsevier B.V. All rights reserved.

Subgroups of Paediatric Acute Lymphoblastic Leukaemia Might Differ Significantly in Genetic Predisposition to Asparaginase Hypersensitivity.

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Nóra Kutszegi

Full Text Available L-asparaginase (ASP is a key element in the treatment of paediatric acute lymphoblastic leukaemia (ALL. However, hypersensitivity reactions (HSRs to ASP are major challenges in paediatric patients. Our aim was to investigate genetic variants that may influence the risk to Escherichia coli-derived ASP hypersensitivity. Sample and clinical data collection was carried out from 576 paediatric ALL patients who were treated according to protocols from the Berlin-Frankfurt-Münster Study Group. A total of 20 single nucleotide polymorphisms (SNPs in GRIA1 and GALNT10 genes were genotyped. Patients with GRIA1 rs4958351 AA/AG genotype showed significantly reduced risk to ASP hypersensitivity compared to patients with GG genotype in the T-cell ALL subgroup (OR = 0.05 (0.01-0.26; p = 4.70E-04, while no such association was found in pre-B-cell ALL. In the medium risk group two SNPs of GRIA1 (rs2055083 and rs707176 were associated significantly with the occurrence of ASP hypersensitivity (OR = 0.21 (0.09-0.53; p = 8.48E-04 and OR = 3.02 (1.36-6.73; p = 6.76E-03, respectively. Evaluating the genders separately, however, the association of rs707176 with ASP HSRs was confined only to females. Our results suggest that genetic variants of GRIA1 might influence the risk to ASP hypersensitivity, but subgroups of patients can differ significantly in this respect.

Allergic complications of L-asparaginase therapy in children with acute lymphoblastic leukaemia

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Konstantinidis Georgios

2011-01-01

Full Text Available Introduction. L-asparaginase (L-ASP is one of the most effective medications for the treatment of acute lymphoblastic leukaemia (ALL in children, and allergic reactions to the therapy are considered the most significant side effects. Objective. The aim of this study was to determine the prevalence and type of allergic reactions, as well as to identify potential risk factors for the development of allergic reactions during L-ASP therapy in children with ALL. Methods. The study encompassed 70 patients under 18 years of age, who were treated at the Institute for Child and Youth Healthcare of Vojvodina, Novi Sad in the period January 2000 - June 2009. We analyzed the frequency and type of allergic reactions during the administration of L-ASP, the onset of allergic reaction in relation to the phase of therapy of underlying disease, as well as the prevalence of allergic reactions in relation to drug administration method. Results. Allergic reaction manifested in 17 patients (24%. In 14 patients (82% allergic reaction to L-ASP manifested as urticaria, bronchospasm or anaphylaxis, whereas a mild local reaction was observed in only three patients (18%. In a group treated, according to the high-risk protocol, the prevalence of allergic reactions was statistically significantly higher in the intermediate-risk group of patients (p<0.01, i.e. statistically significantly more frequent, as compared to the standard-risk group of patients (p<0.05. The majority of patients (11; 65% developed allergic reactions to the 9th dose of L-ASP, i.e. the first dose during the reinduction phase. The time interval between the last L-ASP dose in the induction phase and the 1st dose in the reinduction phase was at least four weeks. With respect to administration method, the majority of patients (16; 94% developed allergic reaction after intravenous application of L-ASP. Conclusion. Potential risk factors for the development of allergic reaction to L-ASP are a high-risk therapy

Rationale for a pediatric-inspired approach in the adolescent and young adult population with acute lymphoblastic leukemia, with a focus on asparaginase treatment

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Carmelo Rizzari

2014-09-01

Full Text Available In the last two decades great improvements have been made in the treatment of childhood acute lymphoblastic leukemia, with 5-year overall survival rates currently approaching almost 90%. In comparison, results reported in adolescents and young adults (AYAs are relatively poor. In adults, results have improved, but are still lagging behind those obtained in children. Possible reasons for this different pattern of results include an increased incidence of unfavorable and a decreased incidence of favorable cytogenetic abnormalities in AYAs compared with children. Furthermore, in AYAs less intensive treatments (especially lower cumulative doses of drugs such as asparaginase, corticosteroids and methotrexate and longer gaps between courses of chemotherapy are planned compared to those in children. However, although favorable results obtained in AYAs receiving pediatric protocols have been consistently reported in several international collaborative trials, physicians must also be aware of the specific toxicity pattern associated with increased success in AYAs, since an excess of toxicity may compromise overall treatment schedule intensity. Cooperative efforts between pediatric and adult hematologists in designing specific protocols for AYAs are warranted.

Clinical Utility of Ammonia Concentration as a Diagnostic Test in Monitoring of the Treatment with L-Asparaginase in Children with Acute Lymphoblastic Leukemia

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Małgorzata Czogała

2014-01-01

Full Text Available L-asparaginase (ASP is an enzyme used as one of the basic regimens in the acute lymphoblastic leukemia (ALL therapy. Because of the possibility of the enzyme inactivation by antibodies, monitoring of ASP activity is essential. The aim of the study was to examine if plasma concentration of ammonia, a direct product of the reaction catalyzed by ASP, can be used in the assessment of ASP activity. A group of 87 patients with acute lymphoblastic leukemia treated in the Department of Pediatric Oncology and Hematology in Krakow was enrolled to the study. ASP activity and ammonia concentration were measured after ASP administrations during induction. A positive correlation was found between the ammonia concentration and ASP activity (R=0.44; P<0.0001 and between the medium values of ammonia concentration and ASP activity (R=0.56; P<0.0001. The analysis of ROC curves revealed the moderate accuracy of the ammonia concentration values in the ASP activity assessment. It was also found that the medium value of ammonia concentrations can be useful in identification of the patients with low (<100 IU/L and undetectable (<30 IU/L ASP activity. The plasma ammonia concentration may reflect ASP activity and can be useful when a direct measurement of the activity is unavailable.

Kinetics of inclusion body formation and its correlation with the characteristics of protein aggregates in Escherichia coli.

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Arun K Upadhyay

Full Text Available The objective of the research was to understand the structural determinants governing protein aggregation into inclusion bodies during expression of recombinant proteins in Escherichia coli. Recombinant human growth hormone (hGH and asparaginase were expressed as inclusion bodies in E.coli and the kinetics of aggregate formation was analyzed in details. Asparaginase inclusion bodies were of smaller size (200 nm and the size of the aggregates did not increase with induction time. In contrast, the seeding and growth behavior of hGH inclusion bodies were found to be sequential, kinetically stable and the aggregate size increased from 200 to 800 nm with induction time. Human growth hormone inclusion bodies showed higher resistance to denaturants and proteinase K degradation in comparison to those of asparaginase inclusion bodies. Asparaginase inclusion bodies were completely solubilized at 2-3 M urea concentration and could be refolded into active protein, whereas 7 M urea was required for complete solubilization of hGH inclusion bodies. Both hGH and asparaginase inclusion bodies showed binding with amyloid specific dyes. In spite of its low β-sheet content, binding with dyes was more prominent in case of hGH inclusion bodies than that of asparaginase. Arrangements of protein molecules present in the surface as well as in the core of inclusion bodies were similar. Hydrophobic interactions between partially folded amphiphillic and hydrophobic alpha-helices were found to be one of the main determinants of hGH inclusion body formation. Aggregation behavior of the protein molecules decides the nature and properties of inclusion bodies.

Kinetics of Inclusion Body Formation and Its Correlation with the Characteristics of Protein Aggregates in Escherichia coli

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Upadhyay, Arun K.; Murmu, Aruna; Singh, Anupam; Panda, Amulya K.

2012-01-01

The objective of the research was to understand the structural determinants governing protein aggregation into inclusion bodies during expression of recombinant proteins in Escherichia coli. Recombinant human growth hormone (hGH) and asparaginase were expressed as inclusion bodies in E.coli and the kinetics of aggregate formation was analyzed in details. Asparaginase inclusion bodies were of smaller size (200 nm) and the size of the aggregates did not increase with induction time. In contrast, the seeding and growth behavior of hGH inclusion bodies were found to be sequential, kinetically stable and the aggregate size increased from 200 to 800 nm with induction time. Human growth hormone inclusion bodies showed higher resistance to denaturants and proteinase K degradation in comparison to those of asparaginase inclusion bodies. Asparaginase inclusion bodies were completely solubilized at 2–3 M urea concentration and could be refolded into active protein, whereas 7 M urea was required for complete solubilization of hGH inclusion bodies. Both hGH and asparaginase inclusion bodies showed binding with amyloid specific dyes. In spite of its low β-sheet content, binding with dyes was more prominent in case of hGH inclusion bodies than that of asparaginase. Arrangements of protein molecules present in the surface as well as in the core of inclusion bodies were similar. Hydrophobic interactions between partially folded amphiphillic and hydrophobic alpha-helices were found to be one of the main determinants of hGH inclusion body formation. Aggregation behavior of the protein molecules decides the nature and properties of inclusion bodies. PMID:22479486

Magnetic Fe3O4@MCM-41 core-shell nanoparticles functionalized with thiol silane for efficient l-asparaginase immobilization.

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Ulu, Ahmet; Noma, Samir Abbas Ali; Koytepe, Suleyman; Ates, Burhan

2018-06-06

l-Asparaginase (l-ASNase) is a vital enzyme for medical treatment and food industry. Here, we assessed the use of Fe 3 O 4 @Mobil Composition of Matter No. 41 (MCM-41) magnetic nanoparticles as carrier matrix for l-ASNase immobilization. In addition, surface of Fe 3 O 4 @MCM-41 magnetic nanoparticles was functionalized with 3-mercaptopropyltrimethoxysilane (MPTMS) to enhance stability of l-ASNase. The chemical structure, thermal properties, magnetic profile and morphology of the thiol-functionalized Fe 3 O 4 @MCM-41 magnetic nanoparticles were characterized with Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential thermal analysis (DTA), differential scanning calorimetry (DSC), vibrating sample magnetometer (VSM), scanning electron microscope (SEM), energy dispersive X-ray (EDX) spectroscopy and zeta-potential measurement. l-ASNase was covalently immobilized onto the thiol-functionalized Fe 3 O 4 @MCM-41 magnetic nanoparticles. The properties of the immobilized enzyme, including optimum pH, temperature, kinetic parameters, thermal stability, reusability and storage stability were investigated and compared to free one. Immobilized enzyme was found to be stable over a wide range of pH and temperature range than free enzyme. The immobilized l-ASNase also showed higher thermal stability after 180 min incubation at 50 °C. The immobilized enzyme still retained 63% of its original activity after 16 times of reuse. The Km value for the immobilized enzyme was 1.15-fold lower than the free enzyme, which indicates increased affinity for the substrate. Additionally, the immobilized enzyme was active over 65% and 53% after 30 days of storage at 4 °C and room temperature (∼25 °C), respectively. Thereby, the results confirmed that thiol-functionalized Fe 3 O 4 @MCM-41 magnetic nanoparticles had high efficiency for l-ASNase immobilization and improved stability of L-ASNase.

Optimization, purification and characterization of recombinant L ...

African Journals Online (AJOL)

We studied optimal L-asparaginase sequence from GenBank accession number X12746 encoding for Lasparaginase from Erwinia chrysanthemi NCPPB1125. The expression level of recombinant Lasparaginase was determined as 78% of the total proteins. The purified L-asparaginase had a molecular mass of 37 kDa with ...

The impact of prophylactic fresh-frozen plasma and cryoprecipitate on the incidence of central nervous system thrombosis and hemorrhage in children with acute lymphoblastic leukemia receiving asparaginase.

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Abbott, Lesleigh S; Deevska, Mariana; Fernandez, Conrad V; Dix, David; Price, Victoria E; Wang, Hao; Parker, Louise; Yhap, Margaret; Fitzgerald, Colleen; Barnard, Dorothy R; Berman, Jason N

2009-12-10

Asparaginase (ASP) therapy is associated with depletion of antithrombin (AT) and fibrinogen (FG). Potential toxicities include central nervous system thrombosis (CNST) and hemorrhage. Historical practice at the Izaak Walton Killam Health Centre (IWK) involves measuring AT and FG levels after ASP administration and transfusing fresh-frozen plasma (FFP) or cryoprecipitate (CRY) to prevent thrombotic and hemorrhagic complications. To determine whether this reduced these complications in children with acute lymphoblastic leukemia (ALL), incidence, outcome, and clinical characteristics of ASP-related CNST in ALL patients at IWK were compared with a similar cohort from BC Children's Hospital (BCCH), where prophylaxis was not performed. Costs associated with preventative versus expectant management were estimated. From 1990 to 2005, 240 patients were treated at IWK and 479 at BCCH. Seven BCCH patients developed venous CNST (1.5%), compared with none at IWK. CNST occurred exclusively during induction. Six patients received anticoagulation and continued ASP. All 7 patients remain in remission. National Cancer Institute high-risk ALL predicted CNST risk (P = .02), whereas sex, age, race, and body mass index did not. Neither FFP nor CRY protected against CNST, suggesting prophylaxis is unwarranted for unselected ALL patients. However, prophylactic replacement for HR patients in induction may be cost-effective.

Efficacy of pegaspargase in extra nodal natural killer/T-cell lymphoma nasal type: A case report from China

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Xingan Xiong

2015-01-01

Full Text Available Extranodal natural killer (NK/T-cell lymphoma, nasal type, is a rare and highly aggressive disease with a grim prognosis. There is no known satisfactory treatment. The author herein to report one case of L-asparaginase extranodal NK/T-cell lymphoma primary treated with L-asparaginase methotrexate and dexamethasone.

[Soil soluble organic matter, microbial biomass, and enzyme activities in forest plantations in degraded red soil region of Jiangxi Province, China].

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Jiang, Yu-mei; Chen, Cheng-long; Xu, Zhi-hong; Liu, Yuan-qiu; Ouyang, Jing; Wang, Fang

2010-09-01

Taking the adjacent 18-year-old pure Pinus massoniana pure forest (I), P. massoniana, Liquidamber fomosana, and Schima superba mixed forest (II), S. superba pure forest (III), L. fomosana (IV) pure forest, and natural restoration fallow land (CK) in Taihe County of Jiangxi Province as test sites, a comparative study was made on their soil soluble organic carbon (SOC) and nitrogen (SON), soil microbial biomass C (MBC) and N (MBN), and soil urease and asparaginase activities. In 0-10 cm soil layer, the pool sizes of SOC, SON, MBC, and MBN at test sites ranged in 354-1007 mg x kg(-1), 24-73 mg x kg(-1), 203-488 mg x kg(-1), and 24-65 mg x kg(-1), and the soil urease and asparaginase activities were 95-133 mg x kg(-1) x d(-1) and 58-113 mg x kg(-1) x d(-1), respectively. There were significant differences in the pool sizes of SOC, SON, MBC, and MBN and the asparaginase activity among the test sites, but no significant difference was observed in the urease activity. The pool sizes of SOC and SON were in the order of IV > CK > III > I > II, those of MBC and MBN were in the order of CK > IV > III > I > II, and asparaginase activity followed the order of IV > CK > III > II > I. With the increase of soil depth, the pool sizes of SOC, SON, MBC, and MBN and the activities of soil asparaginase and urease decreased. In 0-20 cm soil layer, the SOC, SON, MBC, MBN, total C, and total N were highly correlated with each other, soil asparaginase activity was highly correlated with SOC, SON, TSN, total C, total N, MBC, and MBN, and soil urease activity was highly correlated with SON, TSN, total C, MBC and MBN.

Enhanced extracellular production of L-asparaginase from Bacillus subtilis 168 by B. subtilis WB600 through a combined strategy.

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Feng, Yue; Liu, Song; Jiao, Yun; Gao, Hui; Wang, Miao; Du, Guocheng; Chen, Jian

2017-02-01

L-asparaginase (EC 3.5.1.1, ASN) exhibits great commercial value due to its uses in the food and medicine industry. In this study, we reported the enhanced expression of type II ASN from Bacillus subtilis 168 in B. subtilis WB600 through a combined strategy. First, eight signal peptides (the signal peptide of the ASN, ywbN, yvgO, amyE, oppA, vpr, lipA, and wapA) were used for ASN secretion in B. subtilis by using Hpa II promoter, respectively. The signal peptide wapA achieved the highest extracellular ASN activity (28.91 U/mL). Second, Hpa II promoter was replaced by a strong promoter, P43 promoter, resulting in 38.1 % enhanced ASN activity. By two rounds of error-prone PCR mutation, the P43 promoter variants with remarkably enhanced strength (D7, E2, H6, B2, and F3) were identified. B2 (-28: A → G, -13: A → G) achieved ASN activity up to 51.13 U/mL. Third, after deletion of the N-terminal 25-residues, ASN activity reached 102.41 U/mL, which was 100 % higher than that of the intact ASN. At last, the extracellular ASN of the B. subtilis arrived at 407.6 U/mL (2.5 g/L of ASN protein) in a 3-L bioreactor by using a fed-batch strategy. The purified ASN showed maximal activity at 65 °C and its half-life at 65 °C was 61 min. The K m and k cat of the ASN were 5.29 mM and 54.4 s -1 , respectively. To the best of our knowledge, we obtained the highest yield of ASN in a food-grade host ever reported, which may benefit the industrial production and application of ASN.

Cell-based laboratory evaluation of coagulation activation by antineoplastic drugs for the treatment of lymphoid tumors

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Misae Tsunaka

2016-07-01

Full Text Available Objectives: Combining vorinostat, L-asparaginase, and doxorubicin (Dox led to improved response rates in the treatment of lymphoid tumors. However, deep-vein thrombosis has been noted as one of the most serious side effects with these drugs, and how these regimens cause deep-vein thrombosis is unclear. Methods: We investigated the procoagulant effects of vorinostat, L-asparaginase, and doxorubicin in lymphoid tumors, focusing on tissue factor, phosphatidylserine, and antithrombin. The human vascular endothelial cell line EAhy926 as well as the lymphoid neoplastic cell lines HUT78 (cutaneous T-cell lymphoma, Molt4 (acute T-lymphoblastic leukemia, and Ramos (Burkitt lymphoma were employed to investigate these procoagulant effects. Results: Vorinostat, L-asparaginase, and doxorubicin induced exposure of phosphatidylserine and procoagulant activity on the surface of lymphoid tumor cells. Vorinostat and doxorubicin also induced phosphatidylserine exposure and increased procoagulant activity on EAhy926 cells. Expression of tissue factor antigen was induced by doxorubicin on the surface of each type of cells, whereas expression of tissue factor mRNA was unchanged. Secretion of antithrombin from HepG2 cells was reduced only by L-asparaginase. Conclusion: These data suggest that vorinostat and doxorubicin may induce procoagulant activity in vessels through apoptosis of tumor cells and through phosphatidylserine exposure and/or tissue factor expression on vascular endothelial cells. L-asparaginase may induce a thrombophilic state by reducing the secretion of anticoagulant proteins such as antithrombin. The laboratory methods described here could be useful to evaluate the procoagulant effects of antineoplastic drugs.

Recombinant deamidated mutants of Erwinia chrysanthemi L-asparaginase have similar or increased activity compared to wild-type enzyme.

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Gervais, David; Foote, Nicholas

2014-10-01

The enzyme Erwinia chrysanthemi L-asparaginase (ErA) is an important biopharmaceutical product used in the treatment of acute lymphoblastic leukaemia. Like all proteins, certain asparagine (Asn) residues of ErA are susceptible to deamidation to aspartic acid (Asp), which may be a concern with respect to enzyme activity and potentially to pharmaceutical efficacy. Recombinant ErA mutants containing Asn to Asp changes were expressed, purified and characterised. Two mutants with single deamidation sites (N41D and N281D) were found to have approximately the same specific activity (1,062 and 924 U/mg, respectively) as the wild-type (908 U/mg). However, a double mutant (N41D N281D) had an increased specific activity (1261 U/mg). The N41D mutation conferred a slight increase in the catalytic constant (k cat 657 s(-1)) when compared to the WT (k cat 565 s(-1)), which was further increased in the double mutant, with a k cat of 798 s(-1). Structural analyses showed that the slight changes caused by point mutation of Asn41 to Asp may have reduced the number of hydrogen bonds in this α-helical part of the protein structure, resulting in subtle changes in enzyme turnover, both structurally and catalytically. The increased α-helical content observed with the N41D mutation by circular dichroism spectroscopy correlates with the difference in k cat, but not K m. The N281D mutation resulted in a lower glutaminase activity compared with WT and the N41D mutant, however the N281D mutation also imparted less stability to the enzyme at elevated temperatures. Taken as a whole, these data suggest that ErA deamidation at the Asn41 and Asn281 sites does not affect enzyme activity and should not be a concern during processing, storage or clinical use. The production of recombinant deamidated variants has proven an effective and powerful means of studying the effect of these changes and may be a useful strategy for other biopharmaceutical products.

Construction of Potent Recombinant Strain Through Intergeneric Protoplast Fusion in Endophytic Fungi for Anticancerous Enzymes Production Using Rice Straw.

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El-Gendy, Mervat Morsy Abbas Ahmed; Al-Zahrani, Salha Hassan Mastour; El-Bondkly, Ahmed Mohamed Ahmed

2017-09-01

Among all fungal endophytes isolates derived from different ethno-medical plants, the hyper-yield L-asparaginase and L-glutaminase wild strains Trichoderma sp. Gen 9 and Cladosporium sp. Gen 20 using rice straw under solid-state fermentation (SSF) were selected. The selected strains were used as parents for the intergeneric protoplast fusion program to construct recombinant strain for prompt improvement production of these enzymes in one recombinant strain. Among 21 fusants obtained, the recombinant strain AYA 20-1, with 2.11-fold and 2.58-fold increase in L-asparaginase and L-glutaminase activities more than the parental isolates Trichoderma sp. Gen 9 and Cladosporium sp. Gen 20, respectively, was achieved using rice straw under SSF. Both therapeutic enzymes L-asparaginase and L-glutaminase were purified and characterized from the culture supernatant of the recombinant AYA 20-1 strain with molecular weights of 50.6 and 83.2 kDa, respectively. Both enzymes were not metalloenzymes. Whereas thiol group blocking reagents such as p-chloromercurybenzoate and iodoacetamide totally inhibited L-asparaginase activity, which refer to sulfhydryl groups and cysteine residues involved in its catalytic activity, they have no effect toward L-glutaminase activity. Interestingly, potent anticancer, antioxidant, and antimicrobial activities were detected for both enzymes.

Structural Characterization of the Loop at the Alpha-Subunit C-Terminus of the Mixed Lineage Leukemia Protein Activating Protease Taspase1.

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Johannes van den Boom

Full Text Available Type 2 asparaginases, a subfamily of N-terminal nucleophile (Ntn hydrolases, are activated by limited proteolysis. This activation yields a heterodimer and a loop region at the C-terminus of the α-subunit is released. Since this region is unresolved in all type 2 asparaginase crystal structures but is close to the active site residues, we explored this loop region in six members of the type 2 asparaginase family using homology modeling. As the loop model for the childhood cancer-relevant protease Taspase1 differed from the other members, Taspase1 activation as well as the conformation and dynamics of the 56 amino acids loop were investigated by CD and NMR spectroscopy. We propose a helix-turn-helix motif, which can be exploited as novel anticancer target to inhibit Taspase1 proteolytic activity.

ATF5 polymorphisms influence ATF function and response to treatment in children with childhood acute lymphoblastic leukemia

OpenAIRE

Rousseau, Julie; Gagné, Vincent; Labuda, Malgorzata; Beaubois, Cyrielle; Sinnett, Daniel; Laverdière, Caroline; Moghrabi, Albert; Sallan, Stephen E.; Silverman, Lewis B.; Neuberg, Donna; Kutok, Jeffery L.; Krajinovic, Maja

2011-01-01

Asparaginase is a standard and critical component in the therapy of childhood acute lymphoblastic leukemia. Asparagine synthetase (ASNS) and the basic region leucine zipper activating transcription factor 5 (ATF5) and arginosuccinate synthase 1 (ASS1) have been shown to mediate the antileukemic effect of asparaginase and to display variable expression between leukemia cells that are resistant and sensitive to treatment. Fourteen polymorphisms in the regulatory and coding regions of these gene...

Severe Hypertriglyceridemia During Therapy For Childhood Acute Lymphoblastic Leukemia

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Bhojwani, Deepa; Darbandi, Rashid; Pei, Deqing; Ramsey, Laura B.; Chemaitilly, Wassim; Sandlund, John T.; Cheng, Cheng; Pui, Ching-Hon; Relling, Mary V.; Jeha, Sima; Metzger, Monika L.

2014-01-01

Background Asparaginase and steroids can cause hypertriglyceridemia in children with acute lymphoblastic leukemia (ALL). There are no guidelines for screening or management of patients with severe hypertriglyceridemia (>1000 mg/dL) during ALL therapy. Patients and Methods Fasting lipid profiles were obtained prospectively at 4 time-points for 257 children consecutively enrolled on a frontline ALL study. Risk factors were evaluated by the exact chi-square test. Details of adverse events and management of hypertriglyceridemia were extracted retrospectively. Results Eighteen of 257 (7%) patients developed severe hypertriglyceridemia. Older age and treatment with higher doses of asparaginase and steroids on the standard/high-risk arm were significant risk factors. Severe hypertriglyceridemia was not associated with pancreatitis after adjustment for age and treatment arm or with osteonecrosis after adjustment for age. However, patients with severe hypertriglyceridemia had a 2.5 to 3 times higher risk of thrombosis compared to patients without, albeit the difference was not statistical significant. Of the 30 episodes of severe hypertriglyceridemia in 18 patients, 7 were managed conservatively while the others with pharmacotherapy. Seventeen of 18 patients continued to receive asparaginase and steroids. Triglyceride levels normalized after completion of ALL therapy in all 12 patients with available measurements. Conclusion Asparaginase- and steroid-induced transient hypertriglyceridemia can be adequately managed with dietary modifications and close monitoring without altering chemotherapy. Patients with severe hypertriglyceridemia were not at increased risk of adverse events, with a possible exception of thrombosis. The benefit of pharmacotherapy in decreasing symptoms and potential complications requires further investigation. PMID:25087182

Immobilized enzymes in blood plasma exchangers via radiation grafting

Science.gov (United States)

Gombotz, Wayne; Hoffman, Allan; Schmer, Gottfried; Uenoyama, Satoshi

The enzyme asparaginase was immobilized onto a porous hollow polypropylene (PP) fiber blood plasma exchange device for the treatment of acute lymphocytic leukemia. The devices were first radiation grafted with polymethacrylic acid (poly(MAAc)). This introduces carboxyl groups onto the surface of the fibers. Several variables were studied in the grafting reaction including the effects of solvent type and monomer concentration. The carboxyl groups were activated with N-hydroxy succinimide (NHS) using carbodiimide chemistry. Asparaginase was then covalently immobilized on the activated surfaces. Quantitative relationships were found relating the percent graft to the amount of immobilized enzyme which was active. The enzyme reactor was tested both in vitro and in vivo using a sheep as an animal model.

Enzymology of asparagine metabolism

Energy Technology Data Exchange (ETDEWEB)

Unnithan, S.

1985-01-01

A highly sensitive method for assaying asparagine synthetase and its glutaminase activity simultaneously was developed using reversed-phase high performance liquid chromatography. The amino acids L-aspartate, L-asparagine, L-glutamate, and L-glutamine were separated after derivatization with O-phthaldialdehyde. This assay can detect picomoles of asparagine and glutamate when a fluorescence detector is used. Chemical modification of asparagine synthetase was carried out. Beef pancreatic asparagine synthetase was inactivated by treatment with the sulfhydryl reagent 5,5'-dithiobis(2-nitro benzoic acid), DTNB. Asparagine protected the glutamine-dependent and ammonia-dependent asparagine synthetase activities as well as the glutaminase activity. Kinetic studies with partially inactivated asparagine synthetase showed that the K/sub m/ values for aspartic acid and glutamine did not change when compared with the K/sub m/ values of the control enzyme. The stoichiometry of DTNB inhibition was measured using (/sup 14/C)DTNB. Differences in the enzymology of L-asparaginase sensitive and resistant L5178Y leukemia cells were examined. Finally, the transport characteristics of L-asparaginase sensitive and resistant cells were observed. The L-asparaginase sensitive cells showed a higher rate of transport of the amino acids glycine, serine, asparagine and aspartate into the cytoplasmic pool.

Non-infectious chemotherapy-associated acute toxicities during childhood acute lymphoblastic leukemia therapy

DEFF Research Database (Denmark)

Schmiegelow, Kjeld; Müller, Klaus Gottlob; Mogensen, Signe Sloth

2017-01-01

obstruction syndrome, endocrinopathies (especially steroid-induced adrenal insufficiency and hyperglycemia), high-dose methotrexate-induced nephrotoxicity, asparaginase-associated hypersensitivity, pancreatitis, and hyperlipidemia. Few of the non-infectious acute toxicities are associated with clinically...

A flow-type amperometric sensor in immunoenzyme analysis

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Ivnitskii, D.M.; Aronbaev, D.M.; Kashkin, A.P.; Meringova, L.F.; Yulaev, M.F.

1986-06-01

A portable flow-type amperometric sensor has been made for the immunoenzyme determination of L-asparaginase. The authors show it is possible to determine peroxidase (the marker enzyme) by this method over the concentration range 1.10/sup -11/-4.10/sup -10/ M. The limit of detection for L-asparaginase is 1.8.10/sup -10/ M, which corresponds to clinically significant enzyme concentrations. Various modifications of immunoenzyme analysis (IEA) are used in clinical and research laboratories, and have contributed to diagnosis as regards antigens and serum antibodies. The sensor used here uses the electrical reduction of the molecular ion at the surface of thr measurement electrode. The electrochemical reaction is preceded by a competing antigen-antibody reaction and by the peroxidase oxidation of the iodide in the depressions.

Egyptian Journal of Biochemistry and Molecular Biology - Vol 27, No ...

African Journals Online (AJOL)

Purification And Characterization Of Vigna unguiculata Cultiver Asparaginase · EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. EMM Ali. http://dx.doi.org/10.4314/ejbmb.v27i1.43196 ...

ATTEMPT TO REDUCE ACRYLAMIDE CONTENT IN ROASTED CHICORY

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Gabriela Zięć

2015-02-01

Full Text Available The aim of this study was to reduce the formation of acrylamide during roasting of chicory roots by soaking the fresh roots in a solution of calcium chloride, by the use of different temperature and time of roasting of dried roots, as well as by the addition of the enzyme (asparaginase during roasting of dried roots. It was shown, that with increasing roasting temperature of chicory roots from 100 - 175 ° C the acrylamide content also increased, while at a temperature of 210 ° C the growth was inhibited. Increasing roasting time from 10 - 25 minutes resulted in an increased acrylamide content. Soaking the roots in the CaCl2 solution for 20 minutes reduced the formation of acrylamide during the roasting approximately by 40%, similarly as the application of asparaginase to the dried roots during the roasting process.

PCR detection of ansA from marine bacteria and its sequence characteristics from Bacillus tequilensis NIOS4

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Nayak, S.; Porob, S.; Fernandes, Areena; Meena, R.M.; Ramaiah, N.

As many as 71 marine bacterial DNA extracts were PCR screened for L-asparaginase (ansA), a key gene in anti-cancer molecular-searches. Over 62% (44) of them were positive for ansA gene. The positive cultures were from genera Bacillus...

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African Journals Online (AJOL)

Vol 11, No 61 (2012), Antioxidant and antimicrobial efficacies of Amaranthus polygonoides and its impact on L-asparaginase production, Abstract PDF. Balakrishnan Naveena, TG Narayani, Punniavan Sakthiselvan, Nagarajan Partha. Vol 9, No 17 (2010), Antioxidant and antimutagenic activities of Viscum album fruit ...

African Journal of Biotechnology - Vol 12, No 19 (2013)

African Journals Online (AJOL)

Production and optimization of L-asparaginase by Bacillus sp. KK2S4 from corn cob · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. EA Makky, Jee Jian Ong, Md. Rezaul Karim, CM Lee ...

Antioxidant and antimicrobial efficacies of Amaranthus polygonoides ...

African Journals Online (AJOL)

intel

2012-07-31

Jul 31, 2012 ... polygonoides and its application in L-asparaginase (anti-leukemic enzyme) production. ... production rate was evaluated thorough Monod kinetics and the maximum specific growth ... plasma asparagine depletion, an essential amino acid for ... In this experiment, the superoxide radicals were generated in 3.

Production of Extracellular Anti-leukaemic Enzyme Lasparaginase ...

African Journals Online (AJOL)

Production of L-asparaginase was carried out in three different media, namely, solid-state media, Tryptone Glucose Yeast extract (TGY) broth and Tryptone Fructose Yeast extract (TFY) broth.. The enzyme was purified to near homogeneity by ammonium sulphate precipitation, dialysis, gel filtration on Sephadex G-100 ...

Case Report: A child with acute lymphocytic leukaemia

African Journals Online (AJOL)

The patient was a child aged 5 years who had been diagnosed to have acute lymphocytic leukemia (ALL). Chemotherapy was given with wysolone, vincristine, daunomycin, l-asparaginase, and intrathecal methotrexate. In addition he was given fluconazole and co-trimoxazole to cover infections during the induction period ...

A rare complication in a child undergoing chemotherapy for acute lymphoblastic leukemia: Superior sagittal sinus thrombosis

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Ting-Yao Wang

2011-04-01

Full Text Available We report the case of a 4-year-old boy with acute lymphoblastic leukemia in high-risk group who suffered from generalized tonic-colonic seizure evolving into status epilepticus, and subsequent left hemiparesis during his first reinduction chemotherapy, consisting of dexamethasone, vincristine, l-asparaginase, and epirubicin. Superior sagittal sinus and cerebral venous thrombosis, predominantly in right side, were proved by brain magnetic resonance imaging. After aggressive treatment with low-molecular weight heparin (LMWH, left hemiparesis improved in 1 week. And he was fully ambulatory 3 weeks later. The second cycle of reinduction chemotherapy was conducted smoothly with the concomitant use of LMWH. This case illustrates the strong correlation of the rare thrombotic complication, superior sagittal sinus thrombosis, and hypercoagulable status secondary to combination use of l-asparaginase and corticosteroid. Early and vigilant recognition of superior sagittal sinus thrombosis and prompt anticoagulation with LMWH may prevent further neurological damage.

Mycobacterium tuberculosis exploits asparagine to assimilate nitrogen and resist acid stress during infection.

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Alexandre Gouzy

2014-02-01

Full Text Available Mycobacterium tuberculosis is an intracellular pathogen. Within macrophages, M. tuberculosis thrives in a specialized membrane-bound vacuole, the phagosome, whose pH is slightly acidic, and where access to nutrients is limited. Understanding how the bacillus extracts and incorporates nutrients from its host may help develop novel strategies to combat tuberculosis. Here we show that M. tuberculosis employs the asparagine transporter AnsP2 and the secreted asparaginase AnsA to assimilate nitrogen and resist acid stress through asparagine hydrolysis and ammonia release. While the role of AnsP2 is partially spared by yet to be identified transporter(s, that of AnsA is crucial in both phagosome acidification arrest and intracellular replication, as an M. tuberculosis mutant lacking this asparaginase is ultimately attenuated in macrophages and in mice. Our study provides yet another example of the intimate link between physiology and virulence in the tubercle bacillus, and identifies a novel pathway to be targeted for therapeutic purposes.

Crystal Structure of Human Taspase1, a Crucial Protease Regulating the Function of MLL

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Khan,J.; Dunn, B.; Tong, L.

2005-01-01

Taspase1 catalyzes the proteolytic processing of the mixed lineage leukemia (MLL) nuclear protein, which is required for maintaining Hox gene expression patterns. Chromosomal translocations of the MLL gene are associated with leukemia in infants. Taspase1, a threonine aspartase, is a member of the type 2 asparaginase family, but is the only protease in this family. We report here the crystal structures of human activated Taspase1 and its proenzyme, as well as the characterization of the effects of mutations in the active site region using a newly developed fluorogenic assay. The structure of Taspase1 has significant differences from other asparaginases, especially near the active site. Mutation of the catalytic nucleophile, Thr234, abolishes autocatalytic processing in cis but does not completely block proteolysis in trans. The structure unexpectedly showed the binding of a chloride ion in the active site, and our kinetic studies confirm that chlorides ions are inhibitors of this enzyme at physiologically relevant concentrations.

Recent trends and concepts in the management of leukaemia ...

African Journals Online (AJOL)

The standard drugs used for the induction of remission are vincristine, prednisolone, an antracycline for adults and L-Asparaginase for children. These drugs are used in combination for induction of remission, based on the knowledge of the cell cycle.The recent concepts as regards chemotherapy, involve modifications to ...

Complete Genome Sequence of Photobacterium sp. Strain J15, Isolated from Seawater of Southwestern Johor, Malaysia.

Science.gov (United States)

Roslan, Noordiyanah Nadhirah; Sabri, Suriana; Oslan, Siti Nurbaya; Baharum, Syarul Nataqain; Leow, Thean Chor

2016-07-28

Here, we report the genome sequences of Photobacterium sp. strain J15, isolated from seawater in Johor, Malaysia, with the ability to produce lipase and asparaginase. The PacBio genome sequence analysis of Photobacterium sp. strain J15 generated revealed its potential in producing enzymes with different catalytic functions. Copyright © 2016 Roslan et al.

Optimization of culture variables for the production of L ...

African Journals Online (AJOL)

The analysis revealed that the optimum levels of L-asparagine, lactose and inoculum percentage were found to be 4.00, 3.5 g L−1, and 2.75%, respectively. The maximum enzyme activity in the optimized medium was 19.33 U ml−1. Keywords: Design of experiments (DoE), L-asparaginase, response surface methodology, ...

Microarray based comparative genome-wide expression profiling of ...

African Journals Online (AJOL)

pg

2014-03-05

Mar 5, 2014 ... 45/F. ALL. 18/M. Fever, anaemia, enlarge lymph glands in children. Child having >50-60% blast cells in. TLC, TLC >20,000/cm mm. Vincristine (1.5 mg/m2), doxorubicin (25 mg/m2), prednisone. (40 mg/m2),. L-asparaginase (10,000 units iv/ alternate day), methotrexate. (12 mg/m2intrathecal). ALL. 6/M. ALL.

Urban waste compost: Effects on physical, chemical, and biochemical soil properties

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Giusquiani, P.L.; Gigliotti, G.; Businelli, D. [Istituto di Chimica Agraria dell`Universita, Perugia (Italy)] [and others

1995-01-01

A long-term field experiment was conducted to determine the effect of the additions of urban waste compost on the physical and chemical properties and enzymatic activities in a calcareous soil (Fluventic Xerochrept). Total Porosity (pores >50 pm measured on thin soil sections from undisturbed samples by image analysis) was greater in the plots treated with compost than the control plots due to a larger amount of elongated pores. In the amended plots total and humified organic C, Pb, Cu, and Zn showed a significant increase compared with nonamended plots. Enzymatic activities (L-asparaginase, arylsulphatase, dehydrogenase, phosphodiesterase, and alkaline phosphomonoesterase) were significantly enhanced by the compost addition thus indicating no inhibiting influence of the heavy metals present. The increased levels of the arylsulphatase, dehydrogenase, phosphodiesterase, and phosphomonoesterase activities were significantly correlated with total porosity: the first three with pores ranging from 50 to 1000 {mu}m, mainly with pores 50 to 200 {mu}m in size and phosphomonoesterase only with pores whose size was <500 {mu}m. L-asparaginase activity was not correlated with porosity. Only arylsulphatase, dehydrogenase, and phosphodiesterase were negatively correlated with bulk density. 44 refs., 4 figs., 6 tabs.

LYMPHOME T/NK PRIMITIF DU LARYNx : LOCALISATION ...

African Journals Online (AJOL)

CONCLUSION. En conclusion le lymphome T/Nk du larynx est une entité rare et extrêmement agressive associée à une forte mor- talité. Malgré que le protocole SMiLE ou d'autres régimes contenant la L-asparaginase sont prometteurs dans ce type de lymphome incurable, d'autres essais thérapeu- tiques sont nécessaires ...

Biochemical characterization and comparison of aspartylglucosaminidases secreted in venom of the parasitoid wasps Asobara tabida and Leptopilina heterotoma.

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Quentin Coulette

Full Text Available Aspartylglucosaminidase (AGA is a low-abundance intracellular enzyme that plays a key role in the last stage of glycoproteins degradation, and whose deficiency leads to human aspartylglucosaminuria, a lysosomal storage disease. Surprisingly, high amounts of AGA-like proteins are secreted in the venom of two phylogenetically distant hymenopteran parasitoid wasp species, Asobara tabida (Braconidae and Leptopilina heterotoma (Cynipidae. These venom AGAs have a similar domain organization as mammalian AGAs. They share with them key residues for autocatalysis and activity, and the mature α- and β-subunits also form an (αβ2 structure in solution. Interestingly, only one of these AGAs subunits (α for AtAGA and β for LhAGA is glycosylated instead of the two subunits for lysosomal human AGA (hAGA, and these glycosylations are partially resistant to PGNase F treatment. The two venom AGAs are secreted as fully activated enzymes, they have a similar aspartylglucosaminidase activity and are both also efficient asparaginases. Once AGAs are injected into the larvae of the Drosophila melanogaster host, the asparaginase activity may play a role in modulating their physiology. Altogether, our data provide new elements for a better understanding of the secretion and the role of venom AGAs as virulence factors in the parasitoid wasps' success.

Histogram specification as a method of density modification

International Nuclear Information System (INIS)

Harrison, R.W.

1988-01-01

A new method for improving the quality and extending the resolution of Fourier maps is described. The method is based on a histogram analysis of the electron density. The distribution of electron density values in the map is forced to be 'ideal'. The 'ideal' distribution is assumed to be Gaussian. The application of the method to improve the electron density map for the protein Acinetobacter asparaginase, which is a tetrameric enzyme of molecular weight 140000 daltons, is described. (orig.)

Sequential capillary electrophoresis analysis using optically gated sample injection and UV/vis detection.

Science.gov (United States)

Liu, Xiaoxia; Tian, Miaomiao; Camara, Mohamed Amara; Guo, Liping; Yang, Li

2015-10-01

We present sequential CE analysis of amino acids and L-asparaginase-catalyzed enzyme reaction, by combing the on-line derivatization, optically gated (OG) injection and commercial-available UV-Vis detection. Various experimental conditions for sequential OG-UV/vis CE analysis were investigated and optimized by analyzing a standard mixture of amino acids. High reproducibility of the sequential CE analysis was demonstrated with RSD values (n = 20) of 2.23, 2.57, and 0.70% for peak heights, peak areas, and migration times, respectively, and the LOD of 5.0 μM (for asparagine) and 2.0 μM (for aspartic acid) were obtained. With the application of the OG-UV/vis CE analysis, sequential online CE enzyme assay of L-asparaginase-catalyzed enzyme reaction was carried out by automatically and continuously monitoring the substrate consumption and the product formation every 12 s from the beginning to the end of the reaction. The Michaelis constants for the reaction were obtained and were found to be in good agreement with the results of traditional off-line enzyme assays. The study demonstrated the feasibility and reliability of integrating the OG injection with UV/vis detection for sequential online CE analysis, which could be of potential value for online monitoring various chemical reaction and bioprocesses. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Resveratrol induces cell cycle arrest and apoptosis in malignant NK cells via JAK2/STAT3 pathway inhibition.

Science.gov (United States)

Quoc Trung, Ly; Espinoza, J Luis; Takami, Akiyoshi; Nakao, Shinji

2013-01-01

Natural killer (NK) cell malignancies, particularly aggressive NK cell leukaemias and lymphomas, have poor prognoses. Although recent regimens with L-asparaginase substantially improved outcomes, novel therapeutic approaches are still needed to enhance clinical response. Resveratrol, a naturally occurring polyphenol, has been extensively studied for its anti-inflammatory, cardioprotective and anti-cancer activities. In this study, we investigated the potential anti-tumour activities of resveratrol against the NK cell lines KHYG-1, NKL, NK-92 and NK-YS. Resveratrol induced robust G0/G1 cell cycle arrest, significantly suppressed cell proliferation and induced apoptosis in a dose- and time-dependent manner for all four cell lines. In addition, resveratrol suppressed constitutively active STAT3 in all the cell lines and inhibited JAK2 phosphorylation but had no effect on other upstream mediators of STAT3 activation, such as PTEN, TYK2, and JAK1. Resveratrol also induced downregulation of the anti-apoptotic proteins MCL1 and survivin, two downstream effectors of the STAT3 pathway. Finally, resveratrol induced synergistic effect on the apoptotic and antiproliferative activities of L-asparaginase against KHYG-1, NKL and NK-92 cells. These results suggest that resveratrol may have therapeutic potential against NK cell malignancies. Furthermore, our finding that resveratrol is a bonafide JAK2 inhibitor extends its potential benefits to other diseases with dysregulated JAK2 signaling.

Resveratrol induces cell cycle arrest and apoptosis in malignant NK cells via JAK2/STAT3 pathway inhibition.

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Ly Quoc Trung

Full Text Available Natural killer (NK cell malignancies, particularly aggressive NK cell leukaemias and lymphomas, have poor prognoses. Although recent regimens with L-asparaginase substantially improved outcomes, novel therapeutic approaches are still needed to enhance clinical response. Resveratrol, a naturally occurring polyphenol, has been extensively studied for its anti-inflammatory, cardioprotective and anti-cancer activities. In this study, we investigated the potential anti-tumour activities of resveratrol against the NK cell lines KHYG-1, NKL, NK-92 and NK-YS. Resveratrol induced robust G0/G1 cell cycle arrest, significantly suppressed cell proliferation and induced apoptosis in a dose- and time-dependent manner for all four cell lines. In addition, resveratrol suppressed constitutively active STAT3 in all the cell lines and inhibited JAK2 phosphorylation but had no effect on other upstream mediators of STAT3 activation, such as PTEN, TYK2, and JAK1. Resveratrol also induced downregulation of the anti-apoptotic proteins MCL1 and survivin, two downstream effectors of the STAT3 pathway. Finally, resveratrol induced synergistic effect on the apoptotic and antiproliferative activities of L-asparaginase against KHYG-1, NKL and NK-92 cells. These results suggest that resveratrol may have therapeutic potential against NK cell malignancies. Furthermore, our finding that resveratrol is a bonafide JAK2 inhibitor extends its potential benefits to other diseases with dysregulated JAK2 signaling.

Hypersensitivity reactions to anticancer agents: Data mining of the public version of the FDA adverse event reporting system, AERS

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Sakaeda Toshiyuki

2011-10-01

Full Text Available Abstract Background Previously, adverse event reports (AERs submitted to the US Food and Drug Administration (FDA database were reviewed to confirm platinum agent-associated hypersensitivity reactions. The present study was performed to confirm whether the database could suggest the hypersensitivity reactions caused by anticancer agents, paclitaxel, docetaxel, procarbazine, asparaginase, teniposide, and etoposide. Methods After a revision of arbitrary drug names and the deletion of duplicated submissions, AERs involving candidate agents were analyzed. The National Cancer Institute Common Terminology Criteria for Adverse Events version 4.0 was applied to evaluate the susceptibility to hypersensitivity reactions, and standardized official pharmacovigilance tools were used for quantitative detection of signals, i.e., drug-associated adverse events, including the proportional reporting ratio, the reporting odds ratio, the information component given by a Bayesian confidence propagation neural network, and the empirical Bayes geometric mean. Results Based on 1,644,220 AERs from 2004 to 2009, the signals were detected for paclitaxel-associated mild, severe, and lethal hypersensitivity reactions, and docetaxel-associated lethal reactions. However, the total number of adverse events occurring with procarbazine, asparaginase, teniposide, or etoposide was not large enough to detect signals. Conclusions The FDA's adverse event reporting system, AERS, and the data mining methods used herein are useful for confirming drug-associated adverse events, but the number of co-occurrences is an important factor in signal detection.

Bortezomib interactions with chemotherapy agents in acute leukemia in vitro.

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Horton, Terzah M; Gannavarapu, Anurhadha; Blaney, Susan M; D'Argenio, David Z; Plon, Sharon E; Berg, Stacey L

2006-07-01

Although there is effective chemotherapy for many patients with leukemia, 20% of children and up to 65% of adults relapse. Novel therapies are needed to treat these patients. Leukemia cells are very sensitive to the proteasome inhibitor bortezomib (VELCADE(R), PS-341), which enhances the in vitro cytotoxic effects of dexamethasone and doxorubicin in multiple myeloma. To determine if bortezomib enhances the cytotoxicity of agents used in leukemia, we employed an in vitro tetrazolium-based colorimetric assay (MTT) to evaluate the cytotoxic effects of bortezomib alone and in combination with dexamethasone, vincristine, doxorubicin, cytarabine, asparaginase, geldanamycin, trichostatin A, and the bcl-2 inhibitor HA14.1. We demonstrated that primary leukemia lymphoblasts and leukemia cell lines are sensitive to bortezomib, with an average IC(50) of 12 nM. Qualitative and quantitative bortezomib-drug interactions were evaluated using the universal response surface approach (URSA). Bortezomib was synergistic with dexamethasone in dexamethasone-sensitive leukemia cells, and additive with vincristine, asparaginase, cytarabine, and doxorubicin. The anti-leukemic activity of bortezomib was also additive with geldanamycin and HA14.1, and additive or synergistic with trichostatin A. These results were compared to analysis using the median-dose effect method, which generated complex drug interactions due to differences in dose-response curve sigmoidicities. These data suggest bortezomib could potentiate the cytotoxic effects of combination chemotherapy in patients with leukemia.

Histogram specification as a method of density modification

Energy Technology Data Exchange (ETDEWEB)

Harrison, R.W.

1988-12-01

A new method for improving the quality and extending the resolution of Fourier maps is described. The method is based on a histogram analysis of the electron density. The distribution of electron density values in the map is forced to be 'ideal'. The 'ideal' distribution is assumed to be Gaussian. The application of the method to improve the electron density map for the protein Acinetobacter asparaginase, which is a tetrameric enzyme of molecular weight 140000 daltons, is described.

Immobilization of enzymes and antibodies to radiation grafted polymers for therapeutic and diagnostic applications

Energy Technology Data Exchange (ETDEWEB)

Hoffman, A.S.; Gombotz, W.R.; Uenoyama, S.; Dong, L.C.; Schmer, G.

1986-01-01

Pre-irradiation and mutual radiation grafting were employed to produce poly(methacrylic acid) (MAAc) hydrogels on polypropylene/polyethylene (PP/PE) copolymer films, and porous PP fibers of a plasma filter. A diphenyl picryl hydrazyl (DPPH) assay was developed to measure the surface peroxide concentration of the pre-irradiated PP/PE films prior to grafting. Mutually grafted porous PP fibers were used for subsequent immobilization of L-asparaginase while the mutually grafted PP/PE films were used to immobilize a schistosoma monoclonal antibody.

Metabolic Alterations Caused by KRAS Mutations in Colorectal Cancer Contribute to Cell Adaptation to Glutamine Depletion by Upregulation of Asparagine Synthetase

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Kosuke Toda

2016-11-01

Full Text Available A number of clinical trials have shown that KRAS mutations of colorectal cancer (CRC can predict a lack of responses to anti-epidermal growth factor receptor–based therapy. Recently, there have been several studies to elucidate metabolism reprogramming in cancer. However, it remains to be investigated how mutated KRAS can coordinate the metabolic shift to sustain CRC tumor growth. In this study, we found that KRAS mutation in CRC caused alteration in amino acid metabolism. KRAS mutation causes a marked decrease in aspartate level and an increase in asparagine level in CRC. Using several human CRC cell lines and clinical specimens of primary CRC, we demonstrated that the expression of asparagine synthetase (ASNS, an enzyme that synthesizes asparagine from aspartate, was upregulated by mutated KRAS and that ASNS expression was induced by KRAS-activated signaling pathway, in particular PI3K-AKT-mTOR pathway. Importantly, we demonstrated that KRAS-mutant CRC cells could become adaptive to glutamine depletion through asparagine biosynthesis by ASNS and that asparagine addition could rescue the inhibited growth and viability of cells grown under the glutamine-free condition in vitro. Notably, a pronounced growth suppression of KRAS-mutant CRC was observed upon ASNS knockdown in vivo. Furthermore, combination of L-asparaginase plus rapamycin markedly suppressed the growth of KRAS-mutant CRC xenografts in vivo, whereas either L-asparaginase or rapamycin alone was not effective. These results indicate ASNS might be a novel therapeutic target against CRCs with mutated KRAS.

Haemostasis disturbances in children with acute lymphoblastic leukemia (ALL) - report of two cases

International Nuclear Information System (INIS)

Dus, M.; Samborska, M.; Derwich, K.

2009-01-01

The therapy of acute lymphoblastic leukemia (ALL) in children may be accompanied by numerous treatment-related complications of various etiology and severity. Possible adverse effects include thromboembolic and haemorrhagic events, which occur mainly during the induction or consolidation therapy, since as they are associated with the administration of L-Asparaginase (L-Asp), steroids and central venous access insertion. The aim of this report is to present haemostatic disturbances which occurred in 2 children with All, treated according to the ALL IC BFM 2002 regimen, despite prophylactic measures during intensive chemotherapy. (authors)

Case report

African Journals Online (AJOL)

abp

23 juin 2015 ... J1 à J10 , daunorubicine 80mg J2-J4-J6, étoposide 150mg J1 à J5) et 2 cycles de consolidation (consolidation I: Cytarabine 4,5g ×2/J. J2-J3-J4 , donorubicine 40mg J4 et J5 , consolidation II: cytarabine. 4,5g ×2/J J2-J3-J4 , asparaginase 10000UI J5); La rémission complète post induction I a été maintenue ...

A trombosis story and PRES.

Science.gov (United States)

Kartal, Vural; Zara, Zeynep; Yilmaz, Sema; Ayhan, Aylin; Yoruk, Asim; Timur, Cetin

2014-01-01

Trombosis is seen in children with acute lymphoblastic leukemia during or after L-asparaginase treatment. Posterior reversible encephalopathy syndrome (PRES) is a complex syndrome characterized with sudden hypertension, headache, nausea, vomiting, alteration in the state of consciousness, vision defect and seizures. The cases related to this syndrome have been reportedly seen after eclampsia, organ transplantation, immunsuppressive treatments, autoimmune diseases and chemotherapy. Vasogenic edema occuring in the brain parencyhma constitues the basic pathophysiology. We present a case who developed seizures during treatment for B-cell acute lymphoblastic leukemia and diagnosed as posterior reversible encephalopathy.

Acute Hyperglycemia Associated with Anti-Cancer Medication

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Yul Hwangbo

2017-03-01

Full Text Available Hyperglycemia during chemotherapy occurs in approximately 10% to 30% of patients. Glucocorticoids and L-asparaginase are well known to cause acute hyperglycemia during chemotherapy. Long-term hyperglycemia is also frequently observed, especially in patients with hematologic malignancies treated with L-asparaginase-based regimens and total body irradiation. Glucocorticoid-induced hyperglycemia often develops because of increased insulin resistance, diminished insulin secretion, and exaggerated hepatic glucose output. Screening strategies for this condition include random glucose testing, hemoglobin A1c testing, oral glucose loading, and fasting plasma glucose screens. The management of hyperglycemia starts with insulin or sulfonylurea, depending on the type, dose, and delivery of the glucocorticoid formulation. Mammalian target of rapamycin (mTOR inhibitors are associated with a high incidence of hyperglycemia, ranging from 13% to 50%. Immunotherapy, such as anti-programmed death 1 (PD-1 antibody treatment, induces hyperglycemia with a prevalence of 0.1%. The proposed mechanism of immunotherapy-induced hyperglycemia is an autoimmune process (insulitis. Withdrawal of the PD-1 inhibitor is the primary treatment for severe hyperglycemia. The efficacy of glucocorticoid therapy is not fully established and the decision to resume PD-1 inhibitor therapy depends on the severity of the hyperglycemia. Diabetic patients should achieve optimized glycemic control before initiating treatment, and glucose levels should be monitored periodically in patients initiating mTOR inhibitor or PD-1 inhibitor therapy. With regard to hyperglycemia caused by anti-cancer therapy, frequent monitoring and proper management are important for promoting the efficacy of anti-cancer therapy and improving patients' quality of life.

Equivalence of intrathecal chemotherapy and radiotherapy as central nervous system prophylaxis in children with acute lymphatic leukemia: a pediatric oncology group study

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Sullivan, M.P. (M.D. Anderson Hospital and Tumor Inst., Houston, TX); Chen, T.; Dyment, P.G.; Hvizdala, E.; Steuber, C.P.

1982-10-01

The efficacy of intrathecal (i.t.) chemoprophylaxis was compared with cranial radiotherapy plus i.t. methotrexate (MTX) in a Southwest Oncology Group (SWOG) study accessing 408 patients from September 10, 1974, to October 29, 1976. Randomization was stratified by prognostic groups (PGs) based on age and white blood cell count at diagnosis. All received induction therapy with vincristine and prednisone (Pred); maintenance therapy consisted of daily 6-mercaptopurine and weekly MTX. Consolidation for arm 1 employed cyclophosphamide and L-asparaginase followed by biwekly 5-day courses of parenteral MTX. The first dose of each course of MTX was given i.t. in triple chemoprophylaxis (MTX, hydrocortisone, and cytosine arabinoside). During maintenance, i.t. chemoprophylaxis was bimonthly and 28-day Pred ''pulses'' were given every 3 mo. Arm 2 i.t. chemoprophylaxis was initiated on achievement of remission, and arm 3 i.t. on treatment day 1; both continued 1 yr. Arm 4 induction included two doses of L-asparaginase. On achievement of remission, CNS prophylaxis (radiotherapy, 2400 rad plus i.t. MTX) was given. For all, therapy was discontinued after 3 yr of continuous complete remission. Survival and the incidence of extramedullary relapse were similar for the treatment employing either i.t. chemoprophylaxis or radiotherapy plus i.t. MTX upon achievement of remission. The study indicates that i.t. chemoprophylaxis may be substituted for cranial radiotherapy when utilizing effective systemic regimens. Additionally, chemoprophylaxis may be reduced from 3 to 1 yr in patients with good prognostic factors. (JMT)

Occurrence of Streptomyces aurantiacus in Mangroves of Bhitarkanika

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Gupta, N.

2007-01-01

Full Text Available Thirteen strains of Streptomyces were isolated from phyllosphere of nine mangrove tree species found in Bhitarkanika mangrove ecosystem of Orissa. According to physiological, biochemical data, all 13 of the isolates were taxonomically identified to the genus Streptomyces as aurantiacus species. All strains are grayish, spirals and forming amorphous colony. Almost all utilized araginose, produced H2S, resistant towards rifampicin and penicillin, urea except few strains. However, they exhibited different extracellular activity like phosphate solubilization, lipase and L asparaginase production. This is a unique report from this mangrove ecosystem as far as Streptomyces occurrence is concerned.

Effects of acidity and alkalinity on the stability of amidohydrolases in freshwater

Energy Technology Data Exchange (ETDEWEB)

Frankenberger, W.T. Jr.; Page, A.L.

1983-01-01

The influence of acidity and alkalinity on the enzymatic hydrolysis of amide-N in the aquatic system was investigated by determining the stability of L-asparaginase (EC (Enzyme Commission) 3.5.1.1), L-glutaminase (EC 3.5.1.2), and amidase (EC 3.5.1.4), and urease (EC 3.5.1.5) with respect to pH in three freshwater lakes. The water samples were first incubated at the indicated buffer pH (1-13) for 24 h; then each enzyme was assayed at its optimal pH (pH/sub opt/) under standardized conditions. L-Asparaginase retained essentially 100% of its activity within the pH range of 6-7 in Lake Evans and Lake Matthews, and 5-7 in Lake Perris. L-Glutaminase was active between pH 6 and 7 in the water samples surveyed. Amidase remained completely active at pH ranges of 4-8 in Lake Evans, 4-7 in Lake Matthews, and 5-8 in Lake Perris. Urease remained active over a broad pH range of 5-9 in Lake Evans, 5-8 in Lake Matthews, and 4-8 in Lake Perris. There was a progressive loss in enzyme activity below and above these pH ranges. The results suggest that the decline in aquatic amidohydrolase activities in relation to the pH-profile near their pH/sub opt/ was caused by a reversible reaction involving the ionization or deionization of functional groups of the active center of the protein, but under highly acidic or alkaline conditions (pH <4 to >9) the reduced activitiy appears to be due to irreversible inactivation of the enzyme.

The diagnosis and management of NK/T-cell lymphomas

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Eric Tse

2017-04-01

Full Text Available Abstract Extranodal natural killer (NK/T-cell lymphoma is an aggressive malignancy of putative NK-cell origin, with a minority deriving from the T-cell lineage. Pathologically, the malignancy occurs in two forms, extranodal NK/T-cell lymphoma, nasal type; and aggressive NK-cell leukaemia. Lymphoma occur most commonly (80% in the nose and upper aerodigestive tract, less commonly (20% in non-nasal areas (skin, gastrointestinal tract, testis, salivary gland, and rarely as disseminated disease with a leukemic phase. Genetic analysis showed mutations of genes involved in the JAK/STAT pathway, RNA assembly, epigenetic regulation, and tumor suppression. In initial clinical evaluation, positron emission tomography computed tomography, and quantification of plasma EBV DNA are mandatory as they are useful for response monitoring and prognostication. In stage I/II diseases, combined chemotherapy and radiotherapy (sequentially or concurrently is the best approach. Conventional anthracycline-containing regimens are ineffective and should be replaced by non-anthracycline-containing regimens, preferably including L-asparaginase. Radiotherapy alone is associated with high systemic relapse rates and should be avoided. In stage III/IV diseases, non-anthracycline-regimens-containing L-asparaginase are the standard. In relapsed/refractory cases, blockade of the programmed death protein 1 has recently shown promising results with high response rates. In the era of effective non-anthracycline-containing regimens, autologous haematopoietic stem cell transplantation (HSCT has not been shown to be beneficial. However, allogeneic HSCT may be considered for high-risk or advanced-stage patients in remission or relapsed/refractory patients responding to salvage therapy. Prognostic models taking into account presentation, interim, and end-of-treatment parameters are useful in triaging patients to different treatment strategies.

Impact of herbaceous vegetation on the enzymatic activity of coal mining wastes

Energy Technology Data Exchange (ETDEWEB)

Osmanczyk, D

1980-01-01

Differences in the enzymatic activity of reclaimed and crude dump wastes after coal mining were investigated. Due to the increased activity of six investigated enzymes (dehydrogenase, catalase, saccharase, BETA-glucosidase, urease and asparaginase), a favourable impact of herbaceous vegetation on the biological activation of the breeding-ground was noticed. Particularly in the case of sacharase and BETA-glucosidase, an increase of the enzymatic activity at a rate of several times or even more than ten times speaks not only for an adequate increase of the metabolic rate of carbohydrates but also for specific properties of the habitat which favours an adsorption of these enzymes. (6 refs.) (In Polish)

Non-infectious chemotherapy-associated acute toxicities during childhood acute lymphoblastic leukemia therapy

DEFF Research Database (Denmark)

Schmiegelow, Kjeld; Müller, Klaus Gottlob; Mogensen, Signe Sloth

2017-01-01

During chemotherapy for childhood acute lymphoblastic leukemia, all organs can be affected by severe acute side effects, the most common being opportunistic infections, mucositis, central or peripheral neuropathy (or both), bone toxicities (including osteonecrosis), thromboembolism, sinusoidal...... useful risk factors, and across study groups there has been wide diversity in toxicity definitions, capture strategies, and reporting, thus hampering meaningful comparisons of toxicity incidences for different leukemia protocols. Since treatment of acute lymphoblastic leukemia now yields 5-year overall...... obstruction syndrome, endocrinopathies (especially steroid-induced adrenal insufficiency and hyperglycemia), high-dose methotrexate-induced nephrotoxicity, asparaginase-associated hypersensitivity, pancreatitis, and hyperlipidemia. Few of the non-infectious acute toxicities are associated with clinically...

Thrombotic complications in children with non-Hodgkin lymphoma

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N. V. Lipay

2013-01-01

Full Text Available Our study was aimed at identifying of risk factors of venous thrombosis (VT in children with non-Hodgkin lymphomas. VT episodes were registered in 13 of 174 children treated (7.5 %. Possible impact of morphological type, initial mediastinal involvement, gender, age and use of L-asparaginase as a risk factor of thrombosis development were analyzed. Using multivariate analysis primary mediastinal tumor (OR = 4.73 [CI: 1.42–17.10] and patient age older than 13 years (OR = 4.3 [CI: 1.19–20.28 were identified as prognostic factors of thrombosis development (р < 0,05.

Thrombotic complications in children with non-Hodgkin lymphoma

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N. V. Lipay

2014-07-01

Full Text Available Our study was aimed at identifying of risk factors of venous thrombosis (VT in children with non-Hodgkin lymphomas. VT episodes were registered in 13 of 174 children treated (7.5 %. Possible impact of morphological type, initial mediastinal involvement, gender, age and use of L-asparaginase as a risk factor of thrombosis development were analyzed. Using multivariate analysis primary mediastinal tumor (OR = 4.73 [CI: 1.42–17.10] and patient age older than 13 years (OR = 4.3 [CI: 1.19–20.28 were identified as prognostic factors of thrombosis development (р < 0,05.

New method for immobilization of biomolecules using preirradiation grafting at low temperature

Energy Technology Data Exchange (ETDEWEB)

Liang Chang Dong; Hoffman, A.S.

1986-01-01

A new method of biomolecule immobilization is described in which a monomer-conjugated enzyme (asparaginase, Asp) is grafted together with free monomer (acrylamide, AAm) onto a cellulose sheet which had been preirradiated in a /sup 60/Co source. The preirradiation and grafting steps are carried out in air at - 78/sup 0/C and in vacuum at 0/sup 0/C respectively. The grafting is probably caused by trapped radicals. The immobilized enzyme retains significant activity and is stable to storage. The technique is applicable to immobilization of a wide variety of biomolecules, such as enzymes, antibodies and drugs. The products may be used for therapeutic or diagnostic applications.

A new method for immobilization of biomolecules using preirradiation grafting at low temperature

International Nuclear Information System (INIS)

Liang Chang Dong; Hoffman, A.S.

1986-01-01

A new method of biomolecule immobilization is described in which a monomer-conjugated enzyme (asparaginase, Asp) is grafted together with free monomer (acrylamide, AAm) onto a cellulose sheet which had been preirradiated in a 60 Co source. The preirradiation and grafting steps are carried out in air at - 78 0 C and in vacuum at 0 0 C respectively. The grafting is probably caused by trapped radicals. The immobilized enzyme retains significant activity and is stable to storage. The technique is applicable to immobilization of a wide variety of biomolecules, such as enzymes, antibodies and drugs. The products may be used for therapeutic or diagnostic applications. (author)

Concurrent Chemoradiation Therapy Followed by Consolidation Chemotherapy for Localized Extranodal Natural Killer/T-Cell Lymphoma, Nasal Type

Energy Technology Data Exchange (ETDEWEB)

Oh, Dongryul [Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Ahn, Yong Chan, E-mail: ycahn.ahn@samsung.com [Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Kim, Seok Jin; Kim, Won Seog [Division of Hematology and Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Ko, Young Hyeh [Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

2015-11-01

Purpose: To evaluate the effectiveness of concurrent chemoradiation therapy (CCRT) with 40 Gy followed by consolidation chemotherapy for localized extranodal natural killer (NK)/T-cell lymphoma (ENKTL), nasal type. Methods and Materials: From August 2004 to August 2012, 62 patients with newly diagnosed stage IE to IIE ENKTL underwent CCRT followed by consolidation chemotherapy. The median RT dose was 40 Gy. Cisplatin, 30 mg/m{sup 2}, was administered weekly during the RT course. Responders to CCRT were encouraged to undergo consolidation chemotherapy. Three different consolidation chemotherapy regimens were used consecutively: VIPD (etoposide, ifosfamide, cisplatin, and dexamethasone); VIDL (etoposide, ifosfamide, and dexamethasone followed by intramuscular injection of L-asparaginase); and MIDLE (methotrexate, etoposide, ifosfamide, mesna, and L-asparaginase). Results: The median follow-up period was 49 months (range 8-112). After completion of CCRT, 56 patients (90.3%) had a complete response, 4 (6.4%) had a partial response, 1 (1.6%) had stable disease, and 1 patient (1.6%) had progressive disease (PD). Consolidation chemotherapy was recommended to 61 patients, after excluding the patient with PD, but was actually delivered to 58. Of these 58 patients, 56 (96.5%) had a complete response and 2 (3.5%) had PD. During the follow-up period, 17 patients (including 3 with PD) experienced progression. The median interval to progression was 11 months (range 1-61). Local failure developed in 6 patients, of whom, 2 had developed progression outside the RT field. For all patients, the 3-year overall survival, progression-free survival, and local control rates were 83.1%, 77.1%, and 92.4%, respectively. Grade ≥3 nonhematologic toxicity developed in only 3 patients (4.8%). Conclusions: Excellent clinical outcomes were achieved using CCRT with 40 Gy followed by consolidation chemotherapy. Additional investigation, however, is warranted to confirm our findings.

Chemo-sensitivity in a panel of B-cell precursor acute lymphoblastic leukemia cell lines, YCUB series, derived from children.

Science.gov (United States)

Goto, Hiroaki; Naruto, Takuya; Tanoshima, Reo; Kato, Hiromi; Yokosuka, Tomoko; Yanagimachi, Masakatsu; Fujii, Hisaki; Yokota, Shumpei; Komine, Hiromi

2009-10-01

Sensitivity to 10 anticancer drugs was evaluated in 6 childhood B-cell precursor acute lymphoblastic leukemia (BCP-ALL) cell lines. Authenticity of newly established cell lines was confirmed by genomic fingerprinting. The line YCUB-5R established at relapse was more resistant to 4-hydroperoxy-cyclophosphamide, cytarabine, L-asparaginase, topotecan, fludarabine, and etoposide than YCUB-5 from the same patient at diagnosis. Of the drugs tested, etoposide and SN-38 (irinotecan) showed highest efficacy in the panel, with 50% growth inhibition at 0.22-1.8 microg/ml and 0.57-3.6 ng/ml, respectively. This cell line panel offers an in vitro model for the development of new therapies for childhood BCP-ALL.

Isolation and characterization of bioactive metabolites producing marine Streptomyces parvulus strain sankarensis-A10

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Mobeen Shaik

2017-06-01

Full Text Available The significance and frequency of marine microorganisms as producers of bioactive metabolites-a natural source of drug discovery had varied significantly during the last decades, making marine ecosystem a huge treasure trove of novel isolates and novel compounds. Among the twelve actinomycetes isolated from marine sediment sample (Lat. 17°41′962″N, Long. 83°19′633″E, amylase, protease, lipase and cellulase activities were exhibited by 8,7,4,3 isolates respectively. Five isolates exhibited l-asparaginase activity, while 5, 6, 2 isolates exhibited antibacterial, antifungal and antimicrobial activities respectively. One isolate VMS-A10 efficiently producing alpha-amylase (25.53 ± 0.50 U/mL, protease (19.26 ± 0.25 U/mL, lipase (36.25 ± 0.10 U/mL, cellulase (14.43 ± 0.513 U/mL, l-asparaginase (0.125 ± 0.004 U/mL, antimicrobial metabolites against B. subtilis (503.33 ± 5.77 U/mL, S. aureus (536.66 ± 5.77 U/mL, E. coli (533.33 ± 5.77 U/mL, P. aeruginosa (500.00 ± 10.0 U/mL, MRSA (538.33 ± 5.77 U/mL, C. albicans (353.33 ± 11.54 U/mL and A. niger (443.33 ± 15.27 U/mL was selected, identified on the basis of morphological, cultural, physiological, and biochemical properties together with 16S rDNA sequence, designated as Streptomyces parvulus strain sankarensis-A10 and sequencing product (1490 bp was deposited in the GenBank database under accession number KT906299, Culture Deposit No: NCIM-5601. Isolation and characterization of each potential actinobacteria having immense industrial and therapeutic value on an unprecedented scale from marine sediments of Visakhapatnam coast will have a burgeoning effect.

Non-infectious chemotherapy-associated acute toxicities during childhood acute lymphoblastic leukemia therapy

Science.gov (United States)

Schmiegelow, Kjeld; Müller, Klaus; Mogensen, Signe Sloth; Mogensen, Pernille Rudebeck; Wolthers, Benjamin Ole; Stoltze, Ulrik Kristoffer; Tuckuviene, Ruta; Frandsen, Thomas

2017-01-01

During chemotherapy for childhood acute lymphoblastic leukemia, all organs can be affected by severe acute side effects, the most common being opportunistic infections, mucositis, central or peripheral neuropathy (or both), bone toxicities (including osteonecrosis), thromboembolism, sinusoidal obstruction syndrome, endocrinopathies (especially steroid-induced adrenal insufficiency and hyperglycemia), high-dose methotrexate-induced nephrotoxicity, asparaginase-associated hypersensitivity, pancreatitis, and hyperlipidemia. Few of the non-infectious acute toxicities are associated with clinically useful risk factors, and across study groups there has been wide diversity in toxicity definitions, capture strategies, and reporting, thus hampering meaningful comparisons of toxicity incidences for different leukemia protocols. Since treatment of acute lymphoblastic leukemia now yields 5-year overall survival rates above 90%, there is a need for strategies for assessing the burden of toxicities in the overall evaluation of anti-leukemic therapy programs. PMID:28413626

Aggressive NK-cell leukemia: A rare entity with diagnostic and therapeutic challenge

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Alia Nazarullah

2016-06-01

Full Text Available Aggressive natural killer cell leukemia (ANKL is a rare neoplasm of mature natural killer cells, with an extremely poor overall survival, which is almost always EBV related, with majority of cases reported in East Asia. Here we report the case of an ANKL presenting in a young Hispanic male with secondary hemophagocytosis. Aggressive clinical course, high EBV DNA levels and leukemic presentation, often with associated hemophagocytosis, should raise suspicion of an NK/T-cell neoplasm like ANKL. Due to significant diagnostic overlap with extranodal NK/T-cell lymphoma, nasal type (ENKL, accurate diagnostic classification is crucial due to differing treatment and prognosis. L-asparaginase including chemotherapy followed by allogeneic stem cell transplantation appears to slightly prolong overall survival, but relapse is almost inevitable. Clinical monitoring of EBV DNA levels shows good correlation with disease activity.

Non-infectious chemotherapy-associated acute toxicities during childhood acute lymphoblastic leukemia therapy [version 1; referees: 3 approved

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Kjeld Schmiegelow

2017-04-01

Full Text Available During chemotherapy for childhood acute lymphoblastic leukemia, all organs can be affected by severe acute side effects, the most common being opportunistic infections, mucositis, central or peripheral neuropathy (or both, bone toxicities (including osteonecrosis, thromboembolism, sinusoidal obstruction syndrome, endocrinopathies (especially steroid-induced adrenal insufficiency and hyperglycemia, high-dose methotrexate-induced nephrotoxicity, asparaginase-associated hypersensitivity, pancreatitis, and hyperlipidemia. Few of the non-infectious acute toxicities are associated with clinically useful risk factors, and across study groups there has been wide diversity in toxicity definitions, capture strategies, and reporting, thus hampering meaningful comparisons of toxicity incidences for different leukemia protocols. Since treatment of acute lymphoblastic leukemia now yields 5-year overall survival rates above 90%, there is a need for strategies for assessing the burden of toxicities in the overall evaluation of anti-leukemic therapy programs.

Current issues in dietary acrylamide:formation,mitigation and risk assessment

DEFF Research Database (Denmark)

Pedreschi, F.; Salome Mariotti, M.; Granby, Kit

2014-01-01

content of browned food, while still maintaining its attractive organoleptic properties. Reducing sugars such as glucose and fructose are the major contributors to AA in potato-based products. On the other hand, the limiting substrate of AA formation in cereals and coffee is the free amino acid asparagine....... For some products the addition of glycine or asparaginase reduces AA formation during baking. Since, for potatoes, the limiting substrate is reducing sugars, increases in sugar content in potatoes during storage then introduce some difficulties and potentially quite large variations in the AA content...... of the final product. Sugars in potatoes may be reduced by blanching. Levels of AA in different foods show large variations and no general upper limit is easily applicable, since some formation will always occur. Current policy is that practical measures should be taken voluntarily to reduce AA formation...

Primary NK/T cell lymphoma nasal type of the colon

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Ana María Chirife

2013-02-01

Full Text Available Since nasal NK/T-cell lymphoma and NK/T-cell lymphoma nasal type are rare diseases, colonic involvement has seldom been seen. We report a case of a patient with a primary NK/T-cell lymphoma nasal type of the colon. The patient had no history of malignant diseases and was diagnosed after exhaustive study in the context of fever of unknown origin. The first therapeutic approach followed the DAEPOCH-protocol: etoposide, prednisone, doxor-rubicin, vincristine and cyclophosphamide. The persistence of constitutional symptoms after the first treatment course motivated the switch to a second line following the SMILE-protocol: dexamethasone, metotrexate, ifosfamide, E.coli L-asparaginase, and etoposide. Despite intensive chemotherapy, the patient died 2 months after the diagnose of an extranodal NK/T-cell lymphoma of the colon and 4 months after the first symptomatic appearance of disease.

Radiation dose reduction for patients with extranodal NK/T-cell lymphoma with complete response after initial induction chemotherapy

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Wang L

2016-09-01

Full Text Available Liang Wang,1,2,* Xi-wen Bi,1,3,* Zhong-jun Xia,1,2 Hui-qiang Huang,1,3 Wen-qi Jiang,1,3 Yu-jing Zhang1,4 1State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, 2Department of Hematologic Oncology, 3Department of Medical Oncology, 4Department of Radiation Oncology, Sun Yat-sen University Cancer Center, Guangzhou, People’s Republic of China *These authors contributed equally to this work Abstract: Previous studies have found that radiotherapy (RT dose less than 50 Gy resulted in inferior outcomes for early stage extranodal NK/T-cell lymphoma (ENKTL. Nowadays, induction chemotherapy (CT followed by RT consolidation is often used. For patients who get complete response (CR after CT, whether RT dose can be safely reduced or not remains unknown. This retrospective study compared the survival outcomes between patients who received higher dose (>50 Gy and lower dose (≤50 Gy RT after CR was attained by CT. One hundred and forty four patients of early stage ENKTL got CR after induction CT and received RT consolidation. Thirty-one patients received lower dose RT (median 46 Gy, range, 36–50 Gy, and 113 patients received higher dose RT (median 56 Gy, range, 52–66 Gy. In univariate survival analysis, age >60, local tumor invasion, and non-asparaginase-based CT were associated with inferior progression-free survival (PFS and overall survival (OS. However, there were no differences in PFS and OS between patients treated with higher and lower dose RT, which was confirmed in the multivariate survival analysis. Furthermore, reduced dose RT did not affect local control rate. Most common RT-related side effects were grade 1/2 mucositis and dermatitis, and the incidence rate of grade 3 mucositis or dermatitis was lower in patients treated with reduced dose RT (9.7% vs 15.0% for mucositis, and 6.5% vs 17.7% for dermatitis. In conclusion, this study found that RT dose could be safely reduced without

Improved outcome for children with acute lymphoblastic leukemia after risk-adjusted intensive therapy: a single institution experience

International Nuclear Information System (INIS)

Al-Nasser, A.; El-Solh, H.; Al-Mahr, M.

2008-01-01

Because of need for more comprehensive information on the least toxic and most effective forms of therapy for children with acute lymphoblastic leukemia (ALL), we reviewed our experience in the treatment of children with ALL at King Faisal Specialist Hospital and Research Centre (KFSHRC) and King Fahd National Center for Children's Cancer and Research (KFNCCCR) over a period of 18 years with a focus on patient characteristics and outcome. During the period of 1981 to 1988, records of children with ALL were retrospectively reviewed with respect to clinical presentation, laboratory findings, risk factors, stratification, therapy and outcome. The protocols used in treatment included 4 local protocols (KFSH 81, 84, 87 and 90) and subsequently. Children's Cancer Group (CCG) protocols and these were grouped as Era (1981-1992) and Era 2 (1993-1998). Of 509 children with ALL treated during this period, 316 were treated using local protocols and 193 using CCG protocols. Drugs used in Era 1 included a 4-drug induction using etoposid (VP-16) instead of L-asparaginase. Consolidation was based on high dose methotexate (MTX) 1g/m2 and maintenance was based on oral mercaptopurine (6-MP) and MTX with periodic pulses using intravenous teniposide (VM-26), Ara-C, L-asparaginase, adriamycin, prednisone, VP-16 cyclophosphamide .International protocols were introduced in Era 2, which was also marked by intensification of early treatment, a wider selection of cytoreductive agents, and the alternating use of non-cross-resistant pairs of drugs using the post-remission period. The end of induction remission rate improved from 90% in Era 1 to 95% in Era 2, which was of borderline statistical significance (P=0.49). The 5-year event-free survival (EFS) improved from 30.6% in Era 1 to 64.2% in Era 2 (P<.001). Improvement in outcome was achieved without any significant increase in morbidity or mortality, due to improvement in both systemic therapy and supportive care. The most important

Role of radiation therapy in the treatment of pediatric non-Hodgkin's lymphomas. [Complications of local irradiation and chemotherapy

Energy Technology Data Exchange (ETDEWEB)

Carabell, S.C.; Cassady, J.R.; Weinstein, H.J.; Jaff, N.

1978-11-01

Between 1971 and 1976, 64 patients less than 18 years of age with non-Hodgkin's lymphoma were treated at Boston's Children's Hospital Medical Center-Joint Center for Radiation Therapy. A multimodality approach was used, consisting of radiation therapy (3500 to 4500 rad), surgery, and chemotherapy. Since 1973, all patients have received a regimen initially comprising Adriamycin, Prednisone, 6-Mercaptopurine, Vincristine, and L-Asparaginase. Methotrexate was substituted for Adriamycin following a cumulative total dose of 450 mg/m/sup 2/. The 5-year actuarial survival for all patients was 61%, while relapse-free survival was 54%. The actuarial and relapse-free survival for patients presenting with localized disease was 75% and 72%, respectively. Median follow-up was 40 months and all relapses occurred within 24 months of initial therapy. A multidisciplinary approach, such as the current regimen, offers a good prognosis for this disease.

Radiation sensitivity of fungal microflora isolated from some pharmaceutical ingredients

Energy Technology Data Exchange (ETDEWEB)

Mostafa, S.A. (Ain Shams Univ., Cairo (Egypt). Botany Dept.); El-Zawahry, Y.A.; Abdel All, S.S.

1983-01-01

The total number of fungal microflora of D-glucose, NaCl, KCl and their solutions was determined. The fungal isolates were identified as Aspergillus fumigatus. Aspergillus niger; Spicaria divaricate and Spicaria silvatica and their response to ..gamma..-radiation was determined, the most predominant isolate Asp. fumigatus was also the most irradiation resistant. The Dio and the lethal dose were determined for each isolate in a pure spore suspension as well as in the presence of the other isolates. The higher lethal dose values obtained for pure spore suspension as compared to that obtained for the natural fungal flora a D-glucose are discussed in terms of spore clumping. The activity of amylase, protease and L-asparaginase of Asp. fumigatus was examined prior to and after exposure to different doses of ..gamma..-radiation. Though all were inhibited at high doses, the effect was not as drastic as it was on cell viability.

Pharmacogenetics predictive of response and toxicity in acute lymphoblastic leukemia therapy.

Science.gov (United States)

Mei, Lin; Ontiveros, Evelena P; Griffiths, Elizabeth A; Thompson, James E; Wang, Eunice S; Wetzler, Meir

2015-07-01

Acute lymphoblastic leukemia (ALL) is a relatively rare disease in adults accounting for no more than 20% of all cases of acute leukemia. By contrast with the pediatric population, in whom significant improvements in long term survival and even cure have been achieved over the last 30years, adult ALL remains a significant challenge. Overall survival in this group remains a relatively poor 20-40%. Modern research has focused on improved pharmacokinetics, novel pharmacogenetics and personalized principles to optimize the efficacy of the treatment while reducing toxicity. Here we review the pharmacogenetics of medications used in the management of patients with ALL, including l-asparaginase, glucocorticoids, 6-mercaptopurine, methotrexate, vincristine and tyrosine kinase inhibitors. Incorporating recent pharmacogenetic data, mainly from pediatric ALL, will provide novel perspective of predicting response and toxicity in both pediatric and adult ALL therapies. Copyright © 2015 Elsevier Ltd. All rights reserved.

Chemical, microbial and physical properties of manufactured soils produced by co-composting municipal green waste with coal fly ash

Energy Technology Data Exchange (ETDEWEB)

Belyaeva, O.N.; Haynes, R.J. [University of Queensland, St Lucia, Qld. (Australia)

2009-11-15

Increasing proportions of coal fly ash were co-composted with municipal green waste to produce manufactured soil for landscaping use. Only the 100% green waste treatment reached a thermophilic composting phase ({ge} 50{sup o}C) which lasted for 6 days. The 25% and 50% ash treatments reached 36-38{sup o}C over the same period while little or no self-heating occurred in the 75% and 100% ash treatments. Composted green waste had a low bulk density and high total and macro-porosity. Addition of 25% ash to green waste resulted in a 75% increase in available water holding capacity. As the proportions of added ash in the composts increased, the organic C, soluble C, microbial biomass C, basal respiration and activities of beta-glucosidase, L-asparaginase, alkali phosphatase and arylsulphatase enzymes in the composted products all decreased. It could be concluded that addition of fly ash to green waste at a proportion higher than 25% did not improve the quality parameters of manufactured soil.

Infections During Induction Therapy of Protocol CCLG-2008 in Childhood Acute Lymphoblastic Leukemia: A Single-center Experience with 256 Cases in China

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Si-Dan Li

2015-01-01

Full Text Available Background: Infections remain a major cause of therapy-associated morbidity and mortality in children with acute lymphoblastic leukemia (ALL. Methods: We retrospectively analyzed the medical charts of 256 children treated for ALL under the CCLG-2008 protocol in Beijing Children′s Hospital. Results: There were 65 infectious complications in 50 patients during vincristine, daunorubicin, L-asparaginase and dexamethasone induction therapy, including microbiologically documented infections (n = 12; 18.5%, clinically documented infections (n = 23; 35.3% and fever of unknown origin (n = 30; 46.2%. Neutropenia was present in 83.1% of the infectious episodes. In all, most infections occurred around the 15 th day of induction treatment (n = 28, and no patients died of infection-associated complications. Conclusions: The infections in this study was independent of treatment response, minimal residual diseases at the end of induction therapy, gender, immunophenotype, infection at first visit, risk stratification at diagnosis, unfavorable karyotypes at diagnosis and morphologic type. The infection rate of CCLG-2008 induction therapy is low, and the outcome of patients is favorable.

Metabolic and improved organ scan studies. II. Nitrogen-13 labeled compounds used as in-vivo probes for enzyme therapy and as tumor localizing and organ imaging agents

International Nuclear Information System (INIS)

Anon.

1976-01-01

A number of 13 N-labeled compounds have been enzymatically synthesized and are being evaluated as tumor and/or organ localizing agents. 13 N-Ammonia, produced after cyclotron generation of 13 N-nitrate and subsequent reduction was used to enzymatically aminate the appropriate substrate to yield 13 N-L-glutamic acid, L-glutamine, L-asparagine, L-valine, L-leucine and L-alanine. The use of 13 N-asparagine as a myocardial scanning agent and as a tumor localizing agent in asparaginase-sensitive tumors is discussed. Two imaging devices were used to study the effectiveness of the compounds as localizing agents. For static whole body distribution studies, a dual-detector high energy gamma ray (HEG) rectilinear scanner, equipped with constant response collimators was employed. The uniformity of response of this system permits quantitative determination of the amount of 13 N activity present in the organ or tumor of interest. The total organ kinetic imaging monitor (TOKIM) gamma camera system was used for dynamic studies covering smaller areas of the subject's body

Epstein-Barr Virus-Associated Hemophagocytic Lymphohistiocytosis and Guillain-Barre Syndrome in a 16-Month-Old Child

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Motohiro Matsui MD

2016-03-01

Full Text Available A 16-month-old girl was diagnosed with Epstein-Barr virus hemophagocytic lymphohistiocytosis and transferred to our hospital on the 58th day of the hemophagocytic lymphohistiocytosis after treatment failure according to the Hemophagocytic Lymphohistiocytosis-2004 protocol. On admission to our hospital, she had a flaccid paralysis of her lower limbs. Nerve conduction studies showed a acute motor axonal neuropathy, and a diagnosis of Guillain-Barre syndrome was established. Intravenous immunoglobulin G was started on the 57th day of the Guillain-Barre syndrome. To date, her neurological recovery is incomplete. For hemophagocytic lymphohistiocytosis, after treatment failure of THP-COP regimen (pirarubicin, cyclophosphamide, vincristine, and prednisone and 2 courses of ESCAP regimen (etoposide, prednisone, cytarabine, L-asparaginase, we are now in the process of coordinating unrelated umbilical cord blood transplantation. To the best of our knowledge, we report the youngest case of Guillain-Barre syndrome accompanied by Epstein-Barr virus hemophagocytic lymphohistiocytosis. Rapid progression of Guillain-Barre syndrome, the electrophysiological subtype of Guillain-Barre syndrome, and treatment delay possibly led to poor neurological outcome.

Epstein-Barr Virus-Associated Hemophagocytic Lymphohistiocytosis and Guillain-Barre Syndrome in a 16-Month-Old Child.

Science.gov (United States)

Matsui, Motohiro; Shimizu, Mariko; Ioi, Aya; Mayumi, Azusa; Higuchi, Kohei; Sawada, Akihisa; Sato, Maho; Yasui, Masahiro; Yanagihara, Keiko; Inoue, Masami

2016-01-01

A 16-month-old girl was diagnosed with Epstein-Barr virus hemophagocytic lymphohistiocytosis and transferred to our hospital on the 58th day of the hemophagocytic lymphohistiocytosis after treatment failure according to the Hemophagocytic Lymphohistiocytosis-2004 protocol. On admission to our hospital, she had a flaccid paralysis of her lower limbs. Nerve conduction studies showed a acute motor axonal neuropathy, and a diagnosis of Guillain-Barre syndrome was established. Intravenous immunoglobulin G was started on the 57th day of the Guillain-Barre syndrome. To date, her neurological recovery is incomplete. For hemophagocytic lymphohistiocytosis, after treatment failure of THP-COP regimen (pirarubicin, cyclophosphamide, vincristine, and prednisone) and 2 courses of ESCAP regimen (etoposide, prednisone, cytarabine, L-asparaginase), we are now in the process of coordinating unrelated umbilical cord blood transplantation. To the best of our knowledge, we report the youngest case of Guillain-Barre syndrome accompanied by Epstein-Barr virus hemophagocytic lymphohistiocytosis. Rapid progression of Guillain-Barre syndrome, the electrophysiological subtype of Guillain-Barre syndrome, and treatment delay possibly led to poor neurological outcome.

Lasting engraftment of histoincompatible bone marrow cells in dogs

International Nuclear Information System (INIS)

Vriesendorp, H.M.; Klapwijk, W.M.; van Kessel, A.M.C.; Zurcher, C.; van Bekkum, D.W.

1981-01-01

Conditioning protocols were tested for their efficacy in increasng the incidence of engraftment of histoincompatible dog bone marrow cells. Cyclophosphamide and total body irradiation (TBI), Corynebacterium parvum and TBI, a 3- or 5-day delayed transfusion of bone marrow cells after TBI, or an increase in the number of donor bone marrow cells or lymphocytes appeared to be ineffective. These protocols were previously reported to promote recovery of splenic hemopoiesis in mice in short-term assays. The noted discrepancy between studies with mice and dogs invalidated allogeneic resistance as measured in the mouse spleen assay as a model for bone marrow allograft rejection. Intravenous treatment with silica particles or L-asparaginase did improve the engraftment rate after 7.5 Gy TBI. Low efficiency and significant extra toxicity restrict the applicability of these procedures. The most promising conditioning schedule found appeared to be two fractions of 6.0 Gy TBI separated by a 72-h interval. Prolonged survival was noted after transplantation of bone marrow cells from a one-DLA haplotype-mismatched donor. Possibilities for further improvement of this protocol are discussed

Therapeutic options in peripheral T cell lymphoma

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Yaping Zhang

2016-04-01

Full Text Available Abstract Peripheral T cell lymphoma (PTCL is a rare and heterogeneous group of non-Hodgkin lymphomas with a very poor prognosis. The standard first-line treatments have resulted in unsatisfactory patient outcomes. With the exception of low-risk anaplastic lymphoma kinase (ALK-positive anaplastic large cell lymphoma (ALCL, the majority of patients relapse rapidly; the current 5-year overall survival rates are only 10–30 %. Novel targeted therapies and combination chemotherapies are required for the treatment of patients with PTCL. In recent years, some retrospective and prospective studies have been performed concerning PTCL. Consequently, a number of novel agents and their relevant combination therapies have been identified, including histone deacetylase inhibitors, immunoconjugates, antifolates, monoclonal antibodies, immunomodulatory agents, nucleoside analogs, proteasome inhibitors, kinase inhibitors, bendamustine, l-asparaginase, and other targeted agents. It is hoped that these innovative approaches will finally improve outcomes in patients with PTCL. This review summarizes the currently available approaches for the treatment of PTCL with an emphasis on potential new agents, including the role of stem cell transplantation.

Lasting engraftment of histoincompatible bone marrow cells in dogs

Energy Technology Data Exchange (ETDEWEB)

Vriesendorp, H.M.; Klapwijk, W.M.; van Kessel, A.M.C.; Zurcher, C.; van Bekkum, D.W.

1981-05-01

Conditioning protocols were tested for their efficacy in increasng the incidence of engraftment of histoincompatible dog bone marrow cells. Cyclophosphamide and total body irradiation (TBI), Corynebacterium parvum and TBI, a 3- or 5-day delayed transfusion of bone marrow cells after TBI, or an increase in the number of donor bone marrow cells or lymphocytes appeared to be ineffective. These protocols were previously reported to promote recovery of splenic hemopoiesis in mice in short-term assays. The noted discrepancy between studies with mice and dogs invalidated allogeneic resistance as measured in the mouse spleen assay as a model for bone marrow allograft rejection. Intravenous treatment with silica particles or L-asparaginase did improve the engraftment rate after 7.5 Gy TBI. Low efficiency and significant extra toxicity restrict the applicability of these procedures. The most promising conditioning schedule found appeared to be two fractions of 6.0 Gy TBI separated by a 72-h interval. Prolonged survival was noted after transplantation of bone marrow cells from a one-DLA haplotype-mismatched donor. Possibilities for further improvement of this protocol are discussed.

Marked cytoreduction of a lymphocyte-rich mediastinal thymoma with neoadjuvant chemotherapy in a cat

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Linda J Tong

2015-05-01

Full Text Available Case summary A 15-year-old neutered female domestic shorthair cat presented with lethargy and acute-onset dyspnoea. Thoracic computed tomography (CT revealed a large, cranial mediastinal mass with an estimated volume of 180.7 cm 3 . Chemotherapy consisting of dexamethasone followed by L-asparaginase, prednisolone, vincristine and doxorubicin was commenced owing to the severity of disease and initial possibility of lymphoma. A diagnosis of lymphocyte-rich thymoma was made based upon histological examination, positive pancytokeratin staining, variable lymphocyte CD3 expression and T cell receptor gamma polyclonality. Thoracic CT performed 35 days after the commencement of chemotherapy showed a marked reduction in the size of the mass, with an estimated volume of 9.4 cm 3 . A median sternotomy and thymectomy were performed. No clinical signs have recurred 34 months after surgery. Conclusions and relevance The response to chemotherapy in this case was unusual, and is likely associated with the high non-neoplastic lymphoid component of the mass. The case demonstrates that preoperative chemotherapy can be used to reduce thymoma volume prior to surgery, potentially decreasing anaesthetic risk.

Microbial activities in forest soils exposed to chronic depositions from a lignite power plant

Energy Technology Data Exchange (ETDEWEB)

Klose, S.; Wernecke, K.D.; Makeschin, F. [Technical University of Dresden, Tharandt (Germany)

2004-12-01

Atmospheric emissions of fly ash and SO{sub 2} from lignite-fired power plants strongly affect large forest areas in Germany. The impact of different deposition loads on the microbial biomass and enzyme activities was studied at three forest sites (Picea abies (L.) Karst.) along an emission gradient of 3, 6, and 15 km downwind of a coal-fired power plant, representing high, moderate and low emission rates. An additional site at a distance of 3 km from the power plant was chosen to study the influence of forest type on microbial parameters in coniferous forest soils under fly ash and SO{sub 2} emissions. Soil microbial biomass C and N, CO{sub 2} evolved and activities of L-asparaginase, L-glutaminase, beta-glucosidase, acid phosphatase and arylsulfatase (expressed on dry soil and organic C basis) were determined in the forest floor (L, Of and Oh horizon) and mineral top soil (0-10 cm). It is concluded that chronic fly ash depositions decrease litter decomposition by influencing specific microbial and enzymatic processes in forest soils.

Lasting engraftment of histoincompatible bone marrow cells in dogs

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Vriesendorp, H.M.; Klapwijk, W.M.; van Kessel, A.M.; Zurcher, C.; van Bekkum, D.W.

1981-05-01

Conditioning protocols were tested for their efficacy in increasing the incidence of engraftment of histoincompatible dog bone marrow cells. Cyclophosphamide and total body irradation (TBI), Corynebacterium parvum and TBI, a 3- or 5-day delayed transfusion of bone marrow cells after TBI, or an increase in the number of donor bone marrow cells or lymphocytes appeared to be ineffective. These protocols were previously reported to promote recovery of splenic hemopoiesis in mice in short-term assays. The noted discrepancy between studies with mice and dogs invalidated allogeneic resistance as measured in the mouse spleen assay as a model for bone marrow allograft rejection. Intravenous treatment with silica particles or L-asparaginase did improve the engraftment rate after 7.5 Gy TBI. Low efficiency and significant extra toxicity restrict the applicability of these procedures. The most promising conditioning schedule found appeared to be two fractions of 6.0 Gy TBI separated by a 72-hr interval. Prolonged survival was noted after transplantation of bone marrow cells from a one-DLA haplo-type-mismatched donor. Possibilities for further improvement of this protocol are discussed.

Treatment of feline lymphoma using a 12-week, maintenance-free combination chemotherapy protocol in 26 cats.

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Limmer, S; Eberle, N; Nerschbach, V; Nolte, I; Betz, D

2016-08-01

The aim of this prospective clinical trial was to investigate the efficacy and toxicity of a short-term, maintenance-free chemotherapy protocol in feline lymphoma. Twenty-six cats with confirmed diagnosis of high-/intermediate-grade lymphoma were treated with a 12-week protocol consisting of cyclic administration of l-asparaginase, vincristine, cyclophosphamide, doxorubicin and prednisolone. Complete (CR) and partial remission (PR) rates were 46 and 27%, respectively. Median duration of first CR was 394 days compared with a median PR duration of 41 days. No factor was identified to significantly influence the likelihood to reach CR. Overall survival amounted to 78 days (range: 9-2230 days). Median survival in CR cats was 454 days and in PR cats was 82 days. Toxicosis was mainly low grade with anorexia seen most frequently. In cats achieving CR, maintenance-free chemotherapy may be sufficient to attain long-term remission and survival. Factors aiding in prognosticating the likelihood for CR, strategies enhancing response and targeting chemotherapy-induced anorexia need to be identified in future. © 2014 John Wiley & Sons Ltd.

Biotechnology development for biomedical applications.

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Kuehl, Michael; Brozik, Susan Marie; Rogers, David Michael; Rempe, Susan L.; Abhyankar, Vinay V.; Hatch, Anson V.; Dirk, Shawn M.; Hedberg-Dirk, Elizabeth (University of New Mexico, Albuquerque, NM); Sukharev, Sergei (University of Maryland, College Park, MD); Anishken, Andriy (University of Maryland, College Park, MD); Cicotte, Kirsten; De Sapio, Vincent; Buerger, Stephen P.; Mai, Junyu

2010-11-01

Sandia's scientific and engineering expertise in the fields of computational biology, high-performance prosthetic limbs, biodetection, and bioinformatics has been applied to specific problems at the forefront of cancer research. Molecular modeling was employed to design stable mutations of the enzyme L-asparaginase with improved selectivity for asparagine over other amino acids with the potential for improved cancer chemotherapy. New electrospun polymer composites with improved electrical conductivity and mechanical compliance have been demonstrated with the promise of direct interfacing between the peripheral nervous system and the control electronics of advanced prosthetics. The capture of rare circulating tumor cells has been demonstrated on a microfluidic chip produced with a versatile fabrication processes capable of integration with existing lab-on-a-chip and biosensor technology. And software tools have been developed to increase the calculation speed of clustered heat maps for the display of relationships in large arrays of protein data. All these projects were carried out in collaboration with researchers at the University of Texas M. D. Anderson Cancer Center in Houston, TX.

Salinidade, sodicidade e propriedades microbiológicas de Argissolo cultivado com erva-sal e irrigado com rejeito salino Salinity, sodicity and microbiological properties of an Ultisol cultivated with saltbush and irrigated with saline effluents

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Célia Maria Maganhotto de Souza Silva

2008-10-01

Full Text Available O objetivo deste trabalho foi avaliar o efeito da irrigação com rejeito da dessalinização, oriundo de tanques de produção de tilápia-rosa, sobre as propriedades químicas e microbiológicas de solos cultivados com erva-sal (Atriplex nummularia Lindl.. Quatro áreas foram usadas, das quais duas foram irrigadas com rejeito salino e cultivadas, durante um e cinco anos, com erva-sal. As outras duas áreas foram conduzidas sem irrigação: uma cultivada com vegetação natural e outra com a halófita. Avaliaram-se os parâmetros relativos à salinidade e sodicidade do solo, e também as seguintes características: carbono da biomassa microbiana (Cmic; relação Cmic/carbono orgânico; atividade das enzimas fosfatase ácida, fosfatase alcalina, beta-glucosidase, protease, L-asparaginase, L-glutaminase. A adição de sais afetou as propriedades físicas e químicas dos solos irrigados com rejeito salino, com tendência à salinização e sodificação. A salinidade afetou as propriedades microbiológicas nos solos irrigados, mas o cultivo da halófita favoreceu a produção das enzimas estudadas. O cultivo da erva-sal em áreas que recebem rejeito salino pela irrigação melhora a qualidade biológica dos solos e sua fertilidade, mas não impede a salinização.The objective of this work was to evaluate the effects of irrigation with saline effluents, from red tilapia production ponds, on chemical and microbiological properties of soils cultivated with saltbush (Atriplex nummularia Lindl. Four areas were used, from which two were irrigated with saline waste and cultivated with A. nummularia, during one and five years. The other two areas were not irrigated, and one was cultivated with natural vegetation and the other with the halophyte. The parameters related to soil salinity and sodicity were evaluated, as well as the following characteristics: microbial biomass carbon (Cmic; Cmic/organic carbon; the activity of acid and alcaline phosphatase

Inhibition of IGF1-R overcomes IGFBP7-induced chemotherapy resistance in T-ALL

International Nuclear Information System (INIS)

Bartram, Isabelle; Erben, Ulrike; Ortiz-Tanchez, Jutta; Blunert, Katja; Schlee, Cornelia; Neumann, Martin; Heesch, Sandra; Baldus, Claudia D.

2015-01-01

T-cell acute lymphoblastic leukemia (T-ALL) is a genetically heterogeneous disease with the need for treatment optimization. Previously, high expression of Insulin-like growth factor binding protein 7 (IGFBP7), a member of the IGF system, was identified as negative prognostic factor in adult T-ALL patients. Since aberrant IGFBP7 expression was observed in a variety of neoplasia and was relevant for prognosis in T-ALL, we investigated the functional role of IGFBP7 in Jurkat and Molt-4 cells as in vitro models for T-ALL. Jurkat and Molt-4 cells were stably transfected with an IGFBP7 over-expression vector or the empty vector as control. Proliferation of the cells was assessed by WST-1 assays and cell cycle status was measured by flow-cytometry after BrDU/7-AAD staining. The effect of IGFBP7 over-expression on sensitivity to cytostatic drugs was determined in AnnexinV/7-AAD assays. IGF1-R protein expression was measured by Western Blot and flow-cytometric analysis. IGF1-R associated gene expression profiles were generated from microarray gene expression data of 86 T-ALL patients from the Microarrays Innovations in Leukemia (MILE) multicenter study. IGFBP7-transfected Jurkat cells proliferated less, leading to a longer survival in a nutrient–limited environment. Both IGFBP7-transfected Jurkat and Molt-4 cells showed an arrest in the G0/G1 cell cycle phase. Furthermore, Jurkat IGFBP7-transfected cells were resistant to vincristine and asparaginase treatment. Surface expression and whole protein measurement of IGF1-R protein expression showed a reduced abundance of the receptor after IGFBP7 transfection in Jurkat cells. Interestingly, combination of the IGF1-R inhibitor NPV-AEW541 restored sensitivity to vincristine in IGFBP7-transfected cells. Additionally, IGF1-R associated GEP revealed an up-regulation of important drivers of T-ALL pathogenesis and regulators of chemo-resistance and apoptosis such as NOTCH1, BCL-2, PRKCI, and TP53. This study revealed a

Acute lymphoblastic leukemia in adolescents and young adults.

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Burke, Patrick W; Douer, Dan

2014-01-01

The cure rate of acute lymphoblastic leukemia (ALL) in children is 80%, compared to less than half in adults. A major proportion of this cure rate drop occurs in adolescents and young adults (AYAs). The age range defining this population varies between studies, biological characteristics are different from both younger children and older adults, and AYAs are treated either by pediatric or adult oncologists, who often apply different treatment approaches to the same ALL patient population. The outcome of AYAs aged 15-21 years treated by more contemporary pediatric protocols is similar to that of younger children but is inferior when using adult regimens. This motivated studying AYA patients, including those above the age of 21 years, with pediatric or 'pediatrics-inspired' regimens that intensified nonmyelosuppressive drugs such as vincristine, steroids and asparaginase, with very promising preliminary results. Discovering new mutations in AYA ALL will help stratify patients into risk subgroups and identify targets for novel agents. This, together with fine-tuning pediatric chemotherapy principles will hopefully finally decrease the cure rate gap between children and AYAs - and even older adults. © 2014 S. Karger AG, Basel.

First-line treatment of acute lymphoblastic leukemia with pegasparaginase

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Riccardo Masetti

2009-07-01

Full Text Available Riccardo Masetti, Andrea PessionPediatric Oncology and Hematology Unit “Lalla Seràgnoli”, University of Bologna, Bologna, ItalyAbstract: Acute lymphoblastic leukemia (ALL accounts for almost 4000 cases annually in the United States, approximately two thirds of which are in children and adolescents. Treatment results of ALL have improved considerably in the past decade, due to an optimal stratification of patients and a rational use of different antileukemic agents among which L-asparaginase (L-ASNase plays a fundamental role. This drug has been used in pediatric ALL chemotherapy protocols for almost 3 decades. In the 1970s and 1980s a chemically modified form of this enzyme called pegasparaginase (PEG-ASNase was rationally synthesized to decrease immunogenicity of the enzyme and prolong its half-life. The different advantages of PEG-ASNase have been demonstrated in many clinical studies, the last of which underline the utility of this drug in front-line therapy of ALL. In this review, we discuss the pharmacological advantages and clinical potential of PEG-ASNase and its important use in first-line treatment of ALL.Keywords: pegasparaginase, acute, lymphoblastic leukemia, pegylation

Targeting connective tissue growth factor (CTGF) in acute lymphoblastic leukemia preclinical models: anti-CTGF monoclonal antibody attenuates leukemia growth.

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Lu, Hongbo; Kojima, Kensuke; Battula, Venkata Lokesh; Korchin, Borys; Shi, Yuexi; Chen, Ye; Spong, Suzanne; Thomas, Deborah A; Kantarjian, Hagop; Lock, Richard B; Andreeff, Michael; Konopleva, Marina

2014-03-01

Connective tissue growth factor (CTGF/CCN2) is involved in extracellular matrix production, tumor cell proliferation, adhesion, migration, and metastasis. Recent studies have shown that CTGF expression is elevated in precursor B-acute lymphoblastic leukemia (ALL) and that increased expression of CTGF is associated with inferior outcome in B-ALL. In this study, we characterized the functional role and downstream signaling pathways of CTGF in ALL cells. First, we utilized lentiviral shRNA to knockdown CTGF in RS4;11 and REH ALL cells expressing high levels of CTGF mRNA. Silencing of CTGF resulted in significant suppression of leukemia cell growth compared to control vector, which was associated with AKT/mTOR inactivation and increased levels of cyclin-dependent kinase inhibitor p27. CTGF knockdown sensitized ALL cells to vincristine and methotrexate. Treatment with an anti-CTGF monoclonal antibody, FG-3019, significantly prolonged survival of mice injected with primary xenograft B-ALL cells when co-treated with conventional chemotherapy (vincristine, L-asparaginase and dexamethasone). Data suggest that CTGF represents a targetable molecular aberration in B-ALL, and blocking CTGF signaling in conjunction with administration of chemotherapy may represent a novel therapeutic approach for ALL patients.

Spontaneous perforation of sigmoid colon in a child with acute lymphoblastic leukemia

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Miolski Jelena

2017-01-01

Full Text Available Introduction. Perforation of the sigmoid colon is rare in children and its descriptions in medical literature are infrequent. Case Outline. In a 13-year-old boy with acute lymphoblastic leukemia, a ten-month course of chemotherapy was accompanied by many complications: parasitic infestation (Enterobius vermicularis, lung candidiasis, esophageal candidiasis, steroid diabetes, anaphylactoid reaction to L-asparaginase, febrile neutropenia, mucositis, anemia, thrombocytopenia, enterocolitis, and respiratory distress syndrome. During reinduction treatment, consisting of dexamethasone, vincristine, doxorubicin, and crisantaspase, he complained of abdominal pain and, upon radiographic examination, was found to have pneumoperitoneum. Because of suspicion of abdominal hollow organ perforation, he was subjected to explorative laparotomy, which yielded the diagnosis of perforation of the sigmoid colon. Conclusion. After an extensive review of the published reports on sigmoid perforation, all associated conditions that could possibly induce perforation – such as Hirschsprung’s disease or foreign body – were systematically excluded in our patient. Although typhlitis was the first diagnostic hypothesis, this was excluded by intraoperative findings, histopathology, and perforation site. To the best of our knowledge, this is the first report of a spontaneous perforation of the sigmoid colon in a child with acute lymphoblastic leukemia.

Pharmacological inhibition of fatty-acid oxidation synergistically enhances the effect of L-asparaginase in childhood ALL cells

Czech Academy of Sciences Publication Activity Database

Heřmanová, I.; Arruabarrena-Aristorena, A.; Vališ, Karel; Nůsková, Hana; Alberich-Jorda, Meritxell; Fišer, K.; Fernandez-Ruiz, S.; Kavan, Daniel; Pecinová, Alena; Niso-Santano, N.; Žaliová, M.; Novák, Petr; Houštěk, Josef; Mráček, Tomáš; Kroemer, G.; Carracedo, A.; Trka, J.; Starková, J.

2016-01-01

Roč. 30, č. 1 (2016), s. 209-218 ISSN 0887-6924 R&D Projects: GA ČR(CZ) GBP302/12/G101; GA MZd(CZ) NV15-28848A; GA MŠk LK21307; GA ČR(CZ) GB14-36804G; GA MZd(CZ) NT12370; GA ČR(CZ) GP14-21095P Institutional support: RVO:61388971 ; RVO:67985823 ; RVO:68378050 Keywords : ACUTE LYMPHOBLASTIC-LEUKEMIA * ACUTE MYELOID-LEUKEMIA * OVARIAN-CANCER Subject RIV: CE - Biochemistry; EB - Genetics ; Molecular Biology (UMG-J); EB - Genetics ; Molecular Biology (FGU-C) Impact factor: 11.702, year: 2016

Feasibility of the fluorometric microculture cytotoxicity assay (FMCA) for cytotoxic drug sensitivity testing of tumor cells from patients with acute lymphoblastic leukemia.

Science.gov (United States)

Nygren, P; Kristensen, J; Jonsson, B; Sundström, C; Lönnerholm, G; Kreuger, A; Larsson, R

1992-11-01

The automated fluorometric microculture cytotoxicity assay (FMCA) was used for chemotherapeutic drug sensitivity testing of fresh and cryopreserved tumor cells from patients with acute lymphoblastic leukemia (ALL) at diagnosis and relapse. The technique success rate was 87% for fresh and 81% for cryopreserved samples. Up to 16 different cytotoxic drugs were routinely tested, but neither asparaginase nor methotrexate produced dose-response related cell kill. FMCA data showed good correlation to the well established Disc assay and the drug sensitivity reported by the FMCA was in good agreement with known clinical activity. Samples from children and initial ALL tended to be more drug sensitive than those from adults and ALL at relapse, respectively. For 36 samples clinical outcome was correlated to the quartile position in comparison to all other samples for the most in vitro active drug actually given to the patient. For patients with samples in the first, second, third, and fourth quartiles, the probabilities of complete remission were 89, 57, 38, and 0%, respectively. Using the median value as cut-off line, the sensitivity and specificity of the assay were 87 and 62%, respectively. It is concluded that the FMCA with a minimum of effort and with high success rate report clinically relevant drug sensitivity profiles for ALL.

Elevated temperature altered photosynthetic products in wheat seedlings and organic compounds and biological activity in rhizopshere soil under cadmium stress

Science.gov (United States)

Jia, Xia; Zhao, Yonghua; Wang, Wenke; He, Yunhua

2015-09-01

The objective of this study was to investigate the effects of slightly elevated atmospheric temperature in the spring on photosynthetic products in wheat seedlings and on organic compounds and biological activity in rhizosphere soil under cadmium (Cd) stress. Elevated temperature was associated with increased soluble sugars, reducing sugars, starch, and total sugars, and with decreased amino acids in wheat seedlings under Cd stress. Elevated temperature improved total soluble sugars, free amino acids, soluble phenolic acids, and organic acids in rhizosphere soil under Cd stress. The activity of amylase, phenol oxidase, invertase, β-glucosidase, and L-asparaginase in rhizosphere soil was significantly improved by elevated temperature under Cd stress; while cellulase, neutral phosphatase, and urease activity significantly decreased. Elevated temperature significantly improved bacteria, fungi, actinomycetes, and total microorganisms abundance and fluorescein diacetate activity under Cd stress. In conclusion, slightly elevated atmospheric temperature in the spring improved the carbohydrate levels in wheat seedlings and organic compounds and biological activity in rhizosphere soil under Cd stress in the short term. In addition, elevated atmospheric temperature in the spring stimulated available Cd by affecting pH, DOC, phenolic acids, and organic acids in rhizosphere soil, which resulted in the improvement of the Cd uptake by wheat seedlings.

Bioanalysis of 6-Diazo-5-oxo-L-norleucine (DON) in plasma and brain by ultra-performance liquid chromatography mass spectrometry

Science.gov (United States)

Alt, Jesse; Potter, Michelle C.; Rojas, Camilo; Slusher, Barbara S.

2015-01-01

Glutamine is an abundant amino acid that plays pivotal roles in cell growth, cell metabolism and neurotransmission. Dysregulation of glutamine-utilizing pathways has been associated with pathological conditions such as cancer and neurodegenerative diseases. 6-Diazo-5-Oxo-L-Norleucine (DON) is a reactive glutamine analog that inhibits enzymes affecting glutamine metabolism such as glutaminase, 2-N-amidotransferase, L-asparaginase and several enzymes involved in pyrimidine and purine de novo synthesis. As a result, DON is actively used in preclinical models of cancer and neurodegenerative disease. Moreover, there have been several clinical trials using DON to treat a variety of cancers. Considerations of dose and exposure are especially important with DON treatment due to its narrow therapeutic window and significant side effects. Consequently, a robust quantification bioassay is of interest. DON is a polar unstable molecule which has made quantification challenging. Here we report on the characterization of a bioanalytical method to quantify DON in tissue samples involving DON derivatization with 3N HCl in butanol. The derivatized product is lipophilic and stable. Detection of this analyte by mass spectrometry is fast, specific and can be used to quantify DON in plasma and brain tissue with a limit of detection in the low nanomolar level. PMID:25584882

Metabolomics of the tumor microenvironment in pediatric acute lymphoblastic leukemia.

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Stefano Tiziani

Full Text Available The tumor microenvironment is emerging as an important therapeutic target. Most studies, however, are focused on the protein components, and relatively little is known of how the microenvironmental metabolome might influence tumor survival. In this study, we examined the metabolic profiles of paired bone marrow (BM and peripheral blood (PB samples from 10 children with acute lymphoblastic leukemia (ALL. BM and PB samples from the same patient were collected at the time of diagnosis and after 29 days of induction therapy, at which point all patients were in remission. We employed two analytical platforms, high-resolution magnetic resonance spectroscopy and gas chromatography-mass spectrometry, to identify and quantify 102 metabolites in the BM and PB. Standard ALL therapy, which includes l-asparaginase, completely removed circulating asparagine, but not glutamine. Statistical analyses of metabolite correlations and network reconstructions showed that the untreated BM microenvironment was characterized by a significant network-level signature: a cluster of highly correlated lipids and metabolites involved in lipid metabolism (p<0.006. In contrast, the strongest correlations in the BM upon remission were observed among amino acid metabolites and derivatives (p<9.2 × 10(-10. This study provides evidence that metabolic characterization of the cancer niche could generate new hypotheses for the development of cancer therapies.

Investigations into the influence of airborne pollutants on the metabolism of secondary phenolic substances and amino acids. Untersuchungen ueber den Einfluss von Luftschadstoffen auf den Stoffwechsel von phenolischen Sekundaerstoffen und Aminosaeuren

Energy Technology Data Exchange (ETDEWEB)

Strack, D.

1988-10-01

Quantitative analyses of secondary phenols, free amino acids, and of the enzyme activities arginase and asparaginase were carried out on spruce needles from six different forest sites in North-Rhine Westphalia. In addition, the effects of ozone on spruce aged seven to eight years were investigated. The aim of this was to find out whether there is a correlation between the phenol and amino acid metabolism and the damage rate in older spruce (31 to 60 years) and in younger spruce exposed to ozone. No correlation could be established with a single exception: In one site, the free amino acid pattern showed a 10-fold increase of arginine and an accumulation of ornithine and lysine. This indicates a disturbed nitrogen metabolism, in particular a stimulation of the urea cycle, which may be caused by anthropogenic over fertilizing with nitrogen. The findings for the spruce exposed to ozone indicate a more complex effect on the needle metabolism, which affects both the phenol metabolism (strong decrease of the catechine concentration) and the amino acid metabolism (increase of the alanine concentration). This may be caused by damaged membranes (i.e. higher permeability accompanied by sensitive changes in the metabolic compartmenting) or by a potential increase of transaminase activities. (orig./MG).

Impact of genetic polymorphisms on chemotherapy toxicity in childhood acute lymphoblastic leukemia

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Guillermo eGervasini

2012-11-01

Full Text Available The efficacy of chemotherapy in pediatric acute lymphoblastic leukemia (ALL patients has significantly increased in the last twenty years; as a result, the focus of research is slowly shifting from trying to increase survival rates to reduce chemotherapy-related toxicity.At the present time, the cornerstone of therapy for ALL is still formed by a reduced number of drugs with a highly toxic profile. In recent years, a number of genetic polymorphisms have been identified that can play a significant role in modifying the pharmacokinetics and pharmacodynamics of these drugs. The best example is that of the TPMT gene, whose genotyping is being incorporated to clinical practice in order to individualize doses of mercaptopurine. However, there are additional genes that are relevant for the metabolism, activity and/or transport of other chemotherapy drugs that are widely use in ALL, such as methotrexate, cyclophosphamide, vincristine, L-asparaginase, etoposide, cytarabine or cytotoxic antibiotics. These genes can also be affected by genetic alterations that could therefore have clinical consequences.In this review we will discuss recent data on this field, with special focus on those polymorphisms that could be used in clinical practice to tailor chemotherapy for ALL in order to reduce the occurrence of serious adverse effects.

The periplasmic enzyme, AnsB, of Shigella flexneri modulates bacterial adherence to host epithelial cells.

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Divya T George

Full Text Available S. flexneri strains, most frequently linked with endemic outbreaks of shigellosis, invade the colonic and rectal epithelium of their host and cause severe tissue damage. Here we have attempted to elucidate the contribution of the periplasmic enzyme, L-asparaginase (AnsB to the pathogenesis of S. flexneri. Using a reverse genetic approach we found that ansB mutants showed reduced adherence to epithelial cells in vitro and attenuation in two in vivo models of shigellosis, the Caenorhabditis elegans and the murine pulmonary model. To investigate how AnsB affects bacterial adherence, we compared the proteomes of the ansB mutant with its wild type parental strain using two dimensional differential in-gel electrophoresis and identified the outer membrane protein, OmpA as up-regulated in ansB mutant cells. Bacterial OmpA, is a prominent outer membrane protein whose activity has been found to be required for bacterial pathogenesis. Overexpression of OmpA in wild type S. flexneri serotype 3b resulted in decreasing the adherence of this virulent strain, suggesting that the up-regulation of OmpA in ansB mutants contributes to the reduced adherence of this mutant strain. The data presented here is the first report that links the metabolic enzyme AnsB to S. flexneri pathogenesis.

A case of multiple hepatic abscesses detected by CT scan in the patient with acute lymphoblastic leukemia

International Nuclear Information System (INIS)

Saburi, Yoshio; Shuto, Ryusuke; Mizutani, Ryoko; Hosokawa, Takafumi; Itoga, Takashi

1983-01-01

A 34 years old man admitted to a hospital on 21 Feb. 1983 and was diagnosed acute lymphoblastic leukemia. A hematological complete remission was achieved by combination therapy of vincristine, prednisolone and L-asparaginase. However, he had complaining of high fever and right hypochondralgia since early in Apr. 1983, and it was revealed that elevation of right diaphragm on chest X-ray. Therefore, he was also given several antibiotics (CPZ, TOB, LMOX, PIPC, LCM, AMK, MINO and GM) for complication of probable liver abscess. Remittent fever was persisted in spite of as mentioned above various antibiotics. The multiple hepatic abscesses were found by CT scan of the mid-abdomen as the low density lesions, but bacterial cultures detected no any pathogens. His complaining of remittent fever and right hypochondralgia were improved by treated with Miconazole during about one month, and decreasing in size and number of multiple hepatic abscesses were found by CT scan. Though we could not determined clearly, but suspected that, multiple hepatic abscesses were due to fungus infection, by reason of therapeutic result. Regarding the complication of hepatic abscesses with leukemia, 5 cases have been reported in Japan, and one case out of 5 cases were detected by CT scan. We thought that CT scan were useful procedure for a early diagnosis of hepatic abscesses. In recently, the patient has continued of complete remission hematologically. (author)

Update in Systemic and Targeted Therapies in Gastrointestinal Oncology

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Nelson S. Yee

2018-03-01

Full Text Available Progress has been made in the treatment of gastrointestinal cancers through advances in systemic therapies, surgical interventions, and radiation therapy. At the Multi-Disciplinary Patient Care in Gastrointestinal Oncology conference, the faculty members of the Penn State Health Milton S. Hershey Medical Center presented a variety of topics that focused on this sub-specialty. This conference paper highlights the new development in systemic treatment of various malignant diseases in the digestive system. Results of the recent clinical trials that investigated the clinical efficacy of pegylated hyaluronidase, napabucasin, and L-asparaginase in pancreatic carcinoma are presented. The use of peri-operative chemotherapy comprised of 5-fluorouracil or capecitabine, leucovorin, oxaliplatin, and docetaxel (FLOT, and immunotherapy including pembrolizumab, nivolumab, and ipilimumab in gastroesophageal carcinoma are discussed. Data from clinical trials that investigated the targeted therapeutics including nivolumab, ramucirumab, lenvatinib, and BLU-554 are reported. The role of adjuvant capecitabine in resected biliary tract carcinoma (BTC and nab-paclitaxel in combination with gemcitabine and cisplatin in advanced BTC are presented. In colorectal carcinoma, the efficacy of nivolumab, adjuvant FOLFOX or CAPOX, irinotecan/cetuximab/vemurafenib, and trifluridine/tipiracil/bevacizumab, is examined. In summary, some of the above systemic therapies have become or are expected to become new standard of care, while the others demonstrate the potential of becoming new treatment options.

The amyR-deletion strain of Aspergillus niger CICC2462 is a suitable host strain to express secreted protein with a low background.

Science.gov (United States)

Zhang, Hui; Wang, Shuang; Zhang, Xiang Xiang; Ji, Wei; Song, Fuping; Zhao, Yue; Li, Jie

2016-04-28

The filamentous fungus Aspergillus niger is widely exploited as an important expression host for industrial production. The glucoamylase high-producing strain A. niger CICC2462 has been used as a host strain for the establishment of a secretion expression system. It expresses recombinant xylanase, mannase and asparaginase at a high level, but some high secretory background proteins in these recombinant strains still remain, such as alpha-amylase and alpha-glucosidase; lead to a low-purity of fermentation products. The aim was to construct an A. niger host strain with a low background of protein secretion. The transcription factor amyR was deleted in A. niger CICC2462, and the results from enzyme activity assays and SDS-PAGE analysis showed that the glucoamylase and amylase activities of the ∆amyR strains were significantly lower than those of the wild-type strain. High-throughput RNA-sequencing and shotgun LC-MS/MS proteomic technology analysis demonstrated that the expression of amylolytic enzymes was decreased at both the transcriptional and translational levels in the ∆amyR strain. Interestingly, the ∆amyR strain growth rate better than the wild-type strain. Our findings clearly indicated that the ∆amyR strain of A. niger CICC2462 can be used as a host strain with a low background of protein secretion.

Successful therapy of convoluted T-lymphoblastic lymphoma in the adult

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Levine, A.M.; Forman, S.J.; Meyer, P.R.; Koehler, S.C.; Liebman, H.; Paganini-Hill, A.; Pockros, A.; Lukes, R.J.; Feinstein, D.I.

1983-01-01

Fifteen adult patients with biopsy-proven convoluted T-lymphoblastic lymphoma were treated with an aggressive regimen, modified from the LSA2-L2 protocol used for childhood lymphoma. The treatment schema consisted of induction phase, including cyclophosphamide, vincristine, prednisone, adriamycin, and 2000 rads to mediastinum, as well as intrathecal methotrexate. Consolidation phase included cytosine arabinoside, 6-thioguanine, L-asparaginase, and CCNU, along with cranial irradiation and further intrathecal methotrexate. Maintenance consisted of cyclical chemotherapy and intrathecal methotrexate, continuing for a total of 3 yr. Median age in the group was 25 yr (range 16-73). There were 8 males and 7 females. At diagnosis, 9 patients had mediastinal involvement, and 9 had bone marrow involvement. Five of these demonstrated malignant cells in the peripheral blood. Complete clinical response was attained in 11 patients. Three patients achieved partial response. Four complete responders have relapsed, 1 in the central nervous system at 6 mo. and 1 in nodal sites at 3 mo, 1 in multiple sites at 24 mo. and 1 in bone marrow at 42 mo while off all chemotherapy for 6 mos. At this time, median survival of all patients is 28.3 mo. and median relapse-free survival is 21 mo. The median survival for complete responders in excess of 71 mo. while the median relapse-free survival for this group is 41 mo.

Case of multiple hepatic abscesses detected by CT scan in the patient with acute lymphoblastic leukemia

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Saburi, Yoshio; Shuto, Ryusuke; Mizutani, Ryoko; Hosokawa, Takafumi; Itoga, Takashi (Medical Coll. of Oita (Japan))

1983-12-01

A 34 year old man admitted to a hospital on 21 Feb. 1983 was diagnosed acute lymphoblastic leukemia. A hematological complete remission was achieved by combination therapy of vincristine, prednisolone and L-asparaginase. However, he had been complaining of high fever and right hypochondralgia since early in Apr. 1983, and it was revealed that elevation of right diaphragm on chest X-ray. Therefore, he was also given several antibiotics (CPZ, TOB, LMOX, PIPC, LCM, AMK, MINO and GM) for complication of probable liver abscess. Remittent fever persisted in spite of as mentioned above various antibiotics. The multiple hepatic abscesses were found by CT scan of the mid-abdomen as the low density lesions, but bacterial cultures detected no pathogens. His complaining of remittent fever and right hypochondralgia were improved by treatment with Miconazole during about one month, and decreasing in size and number of multiple hepatic abscesses were found by CT scan. Though we could not determine clearly, but suspected that multiple hepatic abscesses were due to fungus infection, by reason of therapeutic result. Regarding the complication of hepatic abscesses with leukemia, 5 cases have been reported in Japan, and one case out of 5 cases were detected by CT scan. We thought that CT scans were useful procedures for early diagnosis of hepatic abscesses. Recently, the patient has continued complete remission hematologically.

Elevated CO2 benefits the soil microenvironment in the rhizosphere of Robinia pseudoacacia L. seedlings in Cd- and Pb-contaminated soils.

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Huang, Shuping; Jia, Xia; Zhao, Yonghua; Bai, Bo; Chang, Yafei

2017-02-01

Soil contamination by heavy metals in combination with elevated atmospheric CO 2 has important effects on the rhizosphere microenvironment by influencing plant growth. Here, we investigated the response of the R. pseudoacacia rhizosphere microenvironment to elevated CO 2 in combination with cadmium (Cd)- and lead (Pb)-contamination. Organic compounds (total soluble sugars, soluble phenolic acids, free amino acids, and organic acids), microbial abundance and activity, and enzyme activity (urease, dehydrogenase, invertase, and β-glucosidase) in rhizosphere soils increased significantly (p soil microbial community in the rhizosphere. Heavy metals alone resulted in an increase in total soluble sugars, free amino acids, and organic acids, a decrease in phenolic acids, microbial populations and biomass, and enzyme activity, and a change in microbial community in rhizosphere soils. Elevated CO 2 led to an increase in organic compounds, microbial populations, biomass, and activity, and enzyme activity (except for l-asparaginase), and changes in microbial community under Cd, Pb, or Cd + Pb treatments relative to ambient CO 2 . In addition, elevated CO 2 significantly (p soils. Overall, elevated CO 2 benefited the rhizosphere microenvironment of R. pseudoacacia seedlings under heavy metal stress, which suggests that increased atmospheric CO 2 concentrations could have positive effects on soil fertility and rhizosphere microenvironment under heavy metals. Copyright © 2016 Elsevier Ltd. All rights reserved.

Crystal structure of salt-tolerant glutaminase from Micrococcus luteus K-3 in the presence and absence of its product L-glutamate and its activator Tris.

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Yoshimune, Kazuaki; Shirakihara, Yasuo; Wakayama, Mamoru; Yumoto, Isao

2010-02-01

Glutaminase from Micrococcus luteus K-3 [Micrococcus glutaminase (Mglu); 456 amino acid residues (aa); 48 kDa] is a salt-tolerant enzyme. Our previous study determined the structure of its major 42-kDa fragment. Here, using new crystallization conditions, we determined the structures of the intact enzyme in the presence and absence of its product L-glutamate and its activator Tris, which activates the enzyme by sixfold. With the exception of a 'lid' part (26-29 aa) and a few other short stretches, the structures were all very similar over the entire polypeptide chain. However, the presence of the ligands significantly reduced the length of the disordered regions: 41 aa in the unliganded structure (N), 21 aa for L-glutamate (G), 8 aa for Tris (T) and 6 aa for both L-glutamate and Tris (TG). L-glutamate was identified in both the G and TG structures, whereas Tris was only identified in the TG structure. Comparison of the glutamate-binding site between Mglu and salt-labile glutaminase (YbgJ) from Bacillus subtilis showed significantly smaller structural changes of the protein part in Mglu. A comparison of the substrate-binding pocket of Mglu, which is highly specific for L-glutamine, with that of Erwinia carotovora asparaginase, which has substrates other than L-glutamine, shows that Mglu has a larger substrate-binding pocket that prevents the binding of L-asparagine with proper interactions.

Clonal deleted latent membrane protein 1 variants of Epstein-Barr virus are predominant in European extranodal NK/T lymphomas and disappear during successful treatment.

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Halabi, Mohamad Adnan; Jaccard, Arnaud; Moulinas, Rémi; Bahri, Racha; Al Mouhammad, Hazar; Mammari, Nour; Feuillard, Jean; Ranger-Rogez, Sylvie

2016-08-15

Extranodal natural killer/T-cell lymphomas (NK/TL), rare in Europe, are Epstein-Barr virus (EBV) associated lymphomas with poor outcomes. Here, we determined the virus type and analyzed the EBV latent membrane protein-1 (LMP1) gene sequence in NK/TL from French patients. Six clones of viral LMP1 were sequenced by Sanger technology in blood from 13 patients before treatment with an l-asparaginase based regimen and, for 8 of them, throughout the treatment. Blood LMP1 sequences from 21 patients without any known malignancy were tested as controls. EBV Type A was identified for 11/13 patients and for all controls. Before treatment, a clonal LMP1 gene containing a 30 bp deletion (del30) was found in 46.1% of NK/TL and only in 4.8% of controls. Treatment was less effective in these patients who died more rapidly than the others. Patients with a deleted strain evolving toward a wild-type strain during treatment reached complete remission. The LMP1 gene was sequenced by highly sensitive next-generation sequencing technology in five NK/TL nasopharyngeal biopsies, two of them originating from the previous patients. Del30 was present in 100% of the biopsies; two viruses at least coexisted in three biopsies. These results suggest that del30 may be associated with poor prognosis NK/TL and that strain evolution could be used as a potential marker to monitor treatment. © 2016 UICC.

ABDUCENS NERVE PALSY AND THROMBOSIS OF THE CEREBRAL VEINS AND SINUSES - A DIAGNOSTIC PITFALL

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Alexandra J. Tzoukeva

2012-12-01

Full Text Available Thrombosis of the cerebral veins and sinuses is an infrequent cerebrovascular disorder. Because the highly variable symptoms, recent neuroimaging plays a key role in the diagnosis. Abducens nerve palsy as a focal neurological deficit is a rare clinical manifestation in these patients. We present two cases with sudden onset of diplopia and headache. Case 1: A 3-year old girl with B cell lymphoblastic leukemia developed bilateral abducens deficit and bilateral optic disc edema after treatment including L-asparaginase. Thrombosis of the right jugular vein, sagittal and right sigmoid sinuses was visualized on magnetic resonance imaging (MRI and magnetic resonance venography (MRV. Symptoms gradually resolved after treatment with enoxiparine and MRV demonstrated recanalization.Case 2: A 75-year old female with medical history of arterial hypertension presented with headache and sudden left abduction deficit. Computerized tomography (CT scan was normal. MRI and MRV revealed aging brain and disruption of venous flow at the left internal jugular vein, suspecting thrombosis. Extracranial colour duplex sonography and CT angiography proved haemodinamic equivalent of left internal jugular vein thrombosis due to sclerotic pathology of aortic arch.Our first case illustrates the role of improved neuroimaging techniques as the best method for diagnosis of cerebral veins and sinuses thrombosis, presenting with abducens nerve palsy. With second case the potential neuroimaging pitfalls concerning the accurate diagnosis of these cerebrovascular disorders with neuro-ophthalmologic manifestation are discussed.

Altered expression of asparagine synthetase mRNA in human leukemic and carcinoma cell lines

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Goodwin, L.O.; Guzowski, D.E.; Millan, C.A. [North Shore Univ. Hospital/Cornell Univ. Medical College, Manhasset, NY (United States)] [and others

1994-09-01

Asparagine synthetase (AS) is the enzyme responsible for the ATP-dependant conversion of aspartic acid to asparagine. The AS gene is expressed constitutively in most mammalian cells, including cells of the lymphoid lineage, as a 2 kb mRNA. In some leukemic phenotypes, AS expression is abrogated, resulting in no detectable enzyme activity. These cells are rendered sensitive to killing by L-asparaginase, which destroys extracellular asparagine. Prolonged treatment of leukemic cells with this agent can lead to resistance and the reappearance of AS activity, suggesting derepression of the AS gene, which has been shown to be regulated by intracellular levels of asparagine. Modulation of AS expression by asparagine employs cis and trans-acting elements involved in transcriptional and translational regulation. We have cloned and sequenced the human AS gene and surrounding sequence elements as well as the full-length cDNA. Using probes specific to the third and fourth exons of AS, we have identified an additional higher molecular weight mRNA (2.7 kb) in Northern blots derived from a chronic myelogenous leukemia and a colon carcinoma but not in normal lymphocytic or other human cell lines. We speculate that elements present in the cancer-derived mRNAs may be involved in the derepression of AS activity. This hypothesis is being evaluated by RNase protection assays using RNA isolated from a variety of human cell lines to characterize and elucidate the nature of this additional AS encoded message.

Late effects of treatment in survivors of childhood acute lymphoblastic leukaemia

International Nuclear Information System (INIS)

Roux, P.

1987-01-01

The overall aim of this study was a comprehensive assessment of the nature and severity of the late effects of treatment in a group of children surviving acute lymphoblastic leukaemia. In the absence of damage preceding treatment, late effects could be ascribed to treatment. Cranial irradiation, methotrexate, L-asparaginase and cytosine arabinoside are therapeutic modalities most likely to cause injury to the central nervous system. Survivors of childhood leukaemia also showed an increase in weight-for-height during and after therapy which appeared to be the consequence of a loss in statural growth as well as increasing weight-for-age. Assessment of endocrine function in leukaemia survivors indicated abnormalities in the regulation of growth hormone and thyroid stimulating hormone in some patients. Survivors of childhood leukaemia were shown to have an intellectual deficit compared with their siblings and a high incidence of visual-perceptual defects. The intellectual effects of lower doses of cranial irradiation are as yet unknown. A variety of minor neurological abnormalities were detected among leukaemia survivors and thought to be related to preceding central nervous system 'prophylactic' chemotherapy and irradiation. A new instrument, the functional deficit score, was derived to reflect overall outcome in survivors of childhood leukaemia. With few exceptions, leukaemia survivors in this study had received 2400 rads of deep x-ray therapy as cranial irradiation. This dosage has since been reduced world-wide. Current cranial irradiation 'prophylaxis' consists of 1800 rad of megavoltage radiotherapy

Late effects of treatment in survivors of childhood acute lymphoblastic leukaemia

Energy Technology Data Exchange (ETDEWEB)

Roux, P

1987-01-01

The overall aim of this study was a comprehensive assessment of the nature and severity of the late effects of treatment in a group of children surviving acute lymphoblastic leukaemia. In the absence of damage preceding treatment, late effects could be ascribed to treatment. Cranial irradiation, methotrexate, L-asparaginase and cytosine arabinoside are therapeutic modalities most likely to cause injury to the central nervous system. Survivors of childhood leukaemia also showed an increase in weight-for-height during and after therapy which appeared to be the consequence of a loss in statural growth as well as increasing weight-for-age. Assessment of endocrine function in leukaemia survivors indicated abnormalities in the regulation of growth hormone and thyroid stimulating hormone in some patients. Survivors of childhood leukaemia were shown to have an intellectual deficit compared with their siblings and a high incidence of visual-perceptual defects. The intellectual effects of lower doses of cranial irradiation are as yet unknown. A variety of minor neurological abnormalities were detected among leukaemia survivors and thought to be related to preceding central nervous system 'prophylactic' chemotherapy and irradiation. A new instrument, the functional deficit score, was derived to reflect overall outcome in survivors of childhood leukaemia. With few exceptions, leukaemia survivors in this study had received 2400 rads of deep x-ray therapy as cranial irradiation. This dosage has since been reduced world-wide. Current cranial irradiation 'prophylaxis' consists of 1800 rad of megavoltage radiotherapy.

Murine and human leukemias.

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Burchenal, J H

1975-01-01

Essentially all the drugs which are active against human leukemias and lymphomas are active against one type or another of the rodent leukemias and lymphomas. Leukemia L1210 has been generally the most successful screening tool for clinically active compounds. Leukemia P388, however, seems to be better in detecting active antibiotics and natural products and P1534 is particularly sensitive to the Vinca alkaloids, while L5178Y, EARAD, and 6C3HED are useful in detecting the activities of various asparaginase containing fractions. Cell cultures of these leukemias can demonstrate mechanism of drug action and quantitate resistance. Spontaneous AKR leukemia is a model of the advanced human disease. In these leukemias vincristine and prednisone produce a 4 log cell kill. Cytoxan and arabinosyl cytosine (Ara-C) are also effective. On the other hand drugs such as mercaptopurine (6MP) and methotrexate which are highly active in the maintenance phase of acute lymphocytic leukemia (ALL) and in L1210 have little or no activity against the AKR spontaneous system. Mouse leukemias can also detect schedule dependence, synergistic combinations, cross resistance, oral activity, and the ability of drugs to pass the blood brain barrier. A case in point is the Ara-C analog 2,2'-anhydro-arabinofuranosyl-5-fluorocytosine (AAFC) which is not schedule dependent, is active orally, is potentiated by thioguanine, and is effective against intracerebrally inoculated mouse leukemia. AAFC and its analogs might thus be a considerable improvement over Ara-C which is at the present time the most important component of the combination treatment of acute myelogenous leukemia (AML).

Global gene expression analysis of the response of physic nut (Jatropha curcas L.) to medium- and long-term nitrogen deficiency.

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Kuang, Qi; Zhang, Sheng; Wu, Pingzhi; Chen, Yaping; Li, Meiru; Jiang, Huawu; Wu, Guojiang

2017-01-01

Jatropha curcas L. is an important biofuel plant with excellent tolerance of barren environments. However, studies on the regulatory mechanisms that operate in this plant in response to nitrogen (N) shortage are scarce. In this study, genome-wide transcriptional profiles of the roots and leaves of 8-week old physic nut seedlings were analyzed after 2 and 16 days of N starvation. Enrichment results showed that genes associated with N metabolism, processing and regulation of RNA, and transport predominated among those showing alterations in expression. Genes encoding transporter families underwent major changes in expression in both roots and leaves; in particular, those with roles in ammonia, amino acid and peptide transport were generally up-regulated after long-term starvation, while AQUAPORIN genes, whose products function in osmoregulation, were down-regulated. We also found that ASPARA-GINASE B1 and SARCOSINE OXIDASE genes were up-regulated in roots and leaves after 2 and 16 d N starvation. Genes associated with ubiquitination-mediated protein degradation were significantly up-regulated. In addition, genes in the JA biosynthesis pathway were strongly activated while expression of those in GA signaling was inhibited in leaves. We showed that four major classes of genes, those with roles in N uptake, N reutilization, C/N ratio balance, and cell structure and synthesis, were particularly influenced by long-term N limitation. Our discoveries may offer clues to the molecular mechanisms that regulate N reallocation and reutilization so as to maintain or increase plant performance even under adverse environmental conditions.

Discrimination of multilocus sequence typing-based Campylobacter jejuni subgroups by MALDI-TOF mass spectrometry.

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Zautner, Andreas Erich; Masanta, Wycliffe Omurwa; Tareen, Abdul Malik; Weig, Michael; Lugert, Raimond; Groß, Uwe; Bader, Oliver

2013-11-07

Campylobacter jejuni, the most common bacterial pathogen causing gastroenteritis, shows a wide genetic diversity. Previously, we demonstrated by the combination of multi locus sequence typing (MLST)-based UPGMA-clustering and analysis of 16 genetic markers that twelve different C. jejuni subgroups can be distinguished. Among these are two prominent subgroups. The first subgroup contains the majority of hyperinvasive strains and is characterized by a dimeric form of the chemotaxis-receptor Tlp7(m+c). The second has an extended amino acid metabolism and is characterized by the presence of a periplasmic asparaginase (ansB) and gamma-glutamyl-transpeptidase (ggt). Phyloproteomic principal component analysis (PCA) hierarchical clustering of MALDI-TOF based intact cell mass spectrometry (ICMS) spectra was able to group particular C. jejuni subgroups of phylogenetic related isolates in distinct clusters. Especially the aforementioned Tlp7(m+c)(+) and ansB+/ ggt+ subgroups could be discriminated by PCA. Overlay of ICMS spectra of all isolates led to the identification of characteristic biomarker ions for these specific C. jejuni subgroups. Thus, mass peak shifts can be used to identify the C. jejuni subgroup with an extended amino acid metabolism. Although the PCA hierarchical clustering of ICMS-spectra groups the tested isolates into a different order as compared to MLST-based UPGMA-clustering, the isolates of the indicator-groups form predominantly coherent clusters. These clusters reflect phenotypic aspects better than phylogenetic clustering, indicating that the genes corresponding to the biomarker ions are phylogenetically coupled to the tested marker genes. Thus, PCA clustering could be an additional tool for analyzing the relatedness of bacterial isolates.

Pharmacokinetic modeling of an induction regimen for in vivo combined testing of novel drugs against pediatric acute lymphoblastic leukemia xenografts.

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Barbara Szymanska

Full Text Available Current regimens for induction therapy of pediatric acute lymphoblastic leukemia (ALL, or for re-induction post relapse, use a combination of vincristine (VCR, a glucocorticoid, and L-asparaginase (ASP with or without an anthracycline. With cure rates now approximately 80%, robust pre-clinical models are necessary to prioritize active new drugs for clinical trials in relapsed/refractory patients, and the ability of these models to predict synergy/antagonism with established therapy is an essential attribute. In this study, we report optimization of an induction-type regimen by combining VCR, dexamethasone (DEX and ASP (VXL against ALL xenograft models established from patient biopsies in immune-deficient mice. We demonstrate that the VXL combination was synergistic in vitro against leukemia cell lines as well as in vivo against ALL xenografts. In vivo, VXL treatment caused delays in progression of individual xenografts ranging from 22 to >146 days. The median progression delay of xenografts derived from long-term surviving patients was 2-fold greater than that of xenografts derived from patients who died of their disease. Pharmacokinetic analysis revealed that systemic DEX exposure in mice increased 2-fold when administered in combination with VCR and ASP, consistent with clinical findings, which may contribute to the observed synergy between the 3 drugs. Finally, as proof-of-principle we tested the in vivo efficacy of combining VXL with either the Bcl-2/Bcl-xL/Bcl-w inhibitor, ABT-737, or arsenic trioxide to provide evidence of a robust in vivo platform to prioritize new drugs for clinical trials in children with relapsed/refractory ALL.

Multi-agent chemotherapy overcomes glucocorticoid resistance conferred by a BIM deletion polymorphism in pediatric acute lymphoblastic leukemia.

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Sheila Xinxuan Soh

Full Text Available A broad range of anti-cancer agents, including glucocorticoids (GCs and tyrosine kinase inhibitors (TKIs, kill cells by upregulating the pro-apoptotic BCL2 family member, BIM. A common germline deletion in the BIM gene was recently shown to favor the production of non-apoptotic BIM isoforms, and to predict inferior responses in TKI-treated chronic myeloid leukemia (CML and EGFR-driven lung cancer patients. Given that both in vitro and in vivo GC resistance are predictive of adverse outcomes in acute lymphoblastic leukemia (ALL, we hypothesized that this polymorphism would mediate GC resistance, and serve as a biomarker of poor response in ALL. Accordingly, we used zinc finger nucleases to generate ALL cell lines with the BIM deletion, and confirmed the ability of the deletion to mediate GC resistance in vitro. In contrast to CML and lung cancer, the BIM deletion did not predict for poorer clinical outcome in a retrospective analysis of 411 pediatric ALL patients who were uniformly treated with GCs and chemotherapy. Underlying the lack of prognostic significance, we found that the chemotherapy agents used in our cohort (vincristine, L-asparaginase, and methotrexate were each able to induce ALL cell death in a BIM-independent fashion, and resensitize BIM deletion-containing cells to GCs. Together, our work demonstrates how effective therapy can overcome intrinsic resistance in ALL patients, and suggests the potential of using combinations of drugs that work via divergent mechanisms of cell killing to surmount BIM deletion-mediated drug resistance in other cancers.

Preparation and characterization of silk fibroin as a biomaterial with potential for drug delivery

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Zhang Hao

2012-06-01

Full Text Available Abstract Background Degummed silk fibroin from Bombyx mori (silkworm has potential carrier capabilities for drug delivery in humans; however, the processing methods have yet to be comparatively analyzed to determine the differential effects on the silk protein properties, including crystalline structure and activity. Methods In this study, we treated degummed silk with four kinds of calcium-alcohol solutions, and performed secondary structure measurements and enzyme activity test to distinguish the differences between the regenerated fibroins and degummed silk fibroin. Results Gel electrophoresis analysis revealed that Ca(NO32-methanol, Ca(NO32-ethanol, or CaCl2-methanol treatments produced more lower molecular weights of silk fibroin than CaCl2-ethanol. X-ray diffraction and Fourier-transform infrared spectroscopy showed that CaCl2-ethanol produced a crystalline structure with more silk I (α-form, type II β-turn, while the other treatments produced more silk II (β-form, anti-parallel β-pleated sheet. Solid-State 13C cross polarization and magic angle spinning-nuclear magnetic resonance measurements suggested that regenerated fibroins from CaCl2-ethanol were nearly identical to degummed silk fibroin, while the other treatments produced fibroins with significantly different chemical shifts. Finally, enzyme activity test indicated that silk fibroins from CaCl2-ethanol had higher activity when linked to a known chemotherapeutic drug, L-asparaginase, than the fibroins from other treatments. Conclusions Collectively, these results suggest that the CaCl2-ethanol processing method produces silk fibroin with biomaterial properties that are appropriate for drug delivery.

A therapeutic trial of decitabine and vorinostat in combination with chemotherapy for relapsed/refractory acute lymphoblastic leukemia.

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Burke, Michael J; Lamba, Jatinder K; Pounds, Stanley; Cao, Xueyuan; Ghodke-Puranik, Yogita; Lindgren, Bruce R; Weigel, Brenda J; Verneris, Michael R; Miller, Jeffrey S

2014-09-01

DNA hypermethylation and histone deacetylation are pathways of leukemia resistance. We investigated the tolerability and efficacy of decitabine and vorinostat plus chemotherapy in relapse/refractory acute lymphoblastic leukemia (ALL). Decitabine (15 mg/m(2) iv) and vorinostat (230 mg/m(2) PO div BID) were given days 1-4 followed by vincristine, prednisone, PEG-asparaginase, and doxorubicin. Genome wide methylation profiles were performed in 8 matched patient bone marrow (BM) samples taken at day 0 and day 5 (postdecitabine). The median age was 16 (range, 3-54) years. All patients had a prior BM relapse, with five relapsing after allogeneic transplant. The most common nonhematological toxicities possibly related to decitabine or vorinostat were infection with neutropenia (grade 3; n = 4) and fever/neutropenia (grade 3, n = 4; grade 4, n = 1). Of the 13 eligible patients, four achieved complete remission without platelet recovery (CRp), two partial response (PR), one stable disease (SD), one progressive disease (PD), two deaths on study and three patients who did not have end of therapy disease evaluations for an overall response rate of 46.2% (CRp + PR). Following decitabine, significant genome-wide hypo-methylation was observed. Comparison of clinical responders with nonresponders identified methylation profiles of clinical and biological relevance. Decitabine and vorinostat followed by re-Induction chemotherapy was tolerable and demonstrated clinical benefit in relapsed patients with ALL. Methylation differences were identified between responders and nonresponders indicating interpatient variation, which could impact clinical outcome. This study was registered at www.clinicaltrials.gov as NCT00882206. © 2014 Wiley Periodicals, Inc.

Arginase treatment prevents the recovery of canine lymphoma and osteosarcoma cells resistant to the toxic effects of prolonged arginine deprivation.

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Wells, James W; Evans, Christopher H; Scott, Milcah C; Rütgen, Barbara C; O'Brien, Timothy D; Modiano, Jaime F; Cvetkovic, Goran; Tepic, Slobodan

2013-01-01

Rapidly growing tumor cells require a nutrient-rich environment in order to thrive, therefore, restricting access to certain key amino acids, such as arginine, often results in the death of malignant cells, which frequently display defective cell cycle check-point control. Healthy cells, by contrast, become quiescent and remain viable under arginine restriction, displaying full recovery upon return to arginine-rich conditions. The use of arginase therapy to restrict available arginine for selectively targeting malignant cells is currently under investigation in human clinical trials. However, the suitability of this approach for veterinary uses is unexplored. As a prelude to in vivo studies in canine malignancies, we examined the in vitro effects of arginine-deprivation on canine lymphoid and osteosarcoma cell lines. Two lymphoid and 2 osteosarcoma cell lines were unable to recover following 6 days of arginine deprivation, but all remaining cell lines displayed full recovery upon return to arginine-rich culture conditions. These remaining cell lines all proved susceptible to cell death following the addition of arginase to the cultures. The lymphoid lines were particularly sensitive to arginase, becoming unrecoverable after just 3 days of treatment. Two of the osteosarcoma lines were also susceptible over this time-frame; however the other 3 lines required 6-8 days of arginase treatment to prevent recovery. In contrast, adult progenitor cells from the bone marrow of a healthy dog were able to recover fully following 9 days of culture in arginase. Over 3 days in culture, arginase was more effective than asparaginase in inducing the death of lymphoid lines. These results strongly suggest that short-term arginase treatment warrants further investigation as a therapy for lymphoid malignancies and osteosarcomas in dogs.

Remission rate of acute lymphoblastic leukemia (all) in adolescents and young adults (aya)

International Nuclear Information System (INIS)

Vallacha, A.; Haider, G.; Kumar, D.

2018-01-01

To determine the remission rate in adolescent and young adult (AYA) patients with acute lymphoblastic leukemia (ALL). Study Design:Descriptive study. Place and Duration of Study:Department of Oncology, Jinnah Postgraduate Medical Centre (JPMC), Karachi from January, 2016 to March, 2017. Methodology:Adolescent and young adult (AYA) patients aged 15-39 years, newly diagnosed with acute lymphoblastic leukemia from January, 2016 to March, 2017. Diagnosis was confirmed by bone marrow trephine biopsy and immuno-phenotyping. All the patients were treated with daunorubicin, vincristine, prednisone, and L-asparaginase in the induction phase. The response evaluation was done on day 35 of the induction phase and the remission rate was assessed by the bone marrow examination. Results:Of the total 50 AYA patients diagnosed with ALL, 41 patients could complete induction phase and 9 patients died during the first week of induction, therefore excluded from the study. Forty (97.8%) patients were <35years of age, 28 (68.3%) were male, of female 10 (24.4%) were housewives, 33 (80.5%) patients belonged to Sindh, 28 (68.3%) presented with fever and body ache, 17 (41.5%) patients had precursor B cell type ALL, with 7 (17.1%) patients had hemoglobin of <7 g/dL,11 (26.8%) patients had white cell count of >30x10/sup 9//L, platelet count of <20x103/mu L in 6 (14.6%) patients and complete morphological remission was reported in 29 (70.7%) patients. Conclusion:The remission induction rate was 70.7% in the adolescents and young adults with acute lymphoblastic leukemia at the study centre. (author)

Whole-Genome Analysis of Three Yeast Strains Used for Production of Sherry-Like Wines Revealed Genetic Traits Specific to Flor Yeasts

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Eldarov, Mikhail A.; Beletsky, Alexey V.; Tanashchuk, Tatiana N.; Kishkovskaya, Svetlana A.; Ravin, Nikolai V.; Mardanov, Andrey V.

2018-01-01

Flor yeast strains represent a specialized group of Saccharomyces cerevisiae yeasts used for biological wine aging. We have sequenced the genomes of three flor strains originated from different geographic regions and used for production of sherry-like wines in Russia. According to the obtained phylogeny of 118 yeast strains, flor strains form very tight cluster adjacent to the main wine clade. SNP analysis versus available genomes of wine and flor strains revealed 2,270 genetic variants in 1,337 loci specific to flor strains. Gene ontology analysis in combination with gene content evaluation revealed a complex landscape of possibly adaptive genetic changes in flor yeast, related to genes associated with cell morphology, mitotic cell cycle, ion homeostasis, DNA repair, carbohydrate metabolism, lipid metabolism, and cell wall biogenesis. Pangenomic analysis discovered the presence of several well-known “non-reference” loci of potential industrial importance. Events of gene loss included deletions of asparaginase genes, maltose utilization locus, and FRE-FIT locus involved in iron transport. The latter in combination with a flor-yeast-specific mutation in the Aft1 transcription factor gene is likely to be responsible for the discovered phenotype of increased iron sensitivity and improved iron uptake of analyzed strains. Expansion of the coding region of the FLO11 flocullin gene and alteration of the balance between members of the FLO gene family are likely to positively affect the well-known propensity of flor strains for velum formation. Our study provides new insights in the nature of genetic variation in flor yeast strains and demonstrates that different adaptive properties of flor yeast strains could have evolved through different mechanisms of genetic variation. PMID:29867869

Elevated atmospheric CO2 affected photosynthetic products in wheat seedlings and biological activity in rhizosphere soil under cadmium stress.

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Jia, Xia; Liu, Tuo; Zhao, Yonghua; He, Yunhua; Yang, Mingyan

2016-01-01

The objective of this study was to investigate the effects of elevated CO2 (700 ± 23 μmol mol(-1)) on photosynthetic products in wheat seedlings and on organic compounds and biological activity in rhizosphere soil under cadmium (Cd) stress. Elevated CO2 was associated with decreased quantities of reducing sugars, starch, and soluble amino acids, and with increased quantities of soluble sugars, total sugars, and soluble proteins in wheat seedlings under Cd stress. The contents of total soluble sugars, total free amino acids, total soluble phenolic acids, and total organic acids in the rhizosphere soil under Cd stress were improved by elevated CO2. Compared to Cd stress alone, the activity of amylase, phenol oxidase, urease, L-asparaginase, β-glucosidase, neutral phosphatase, and fluorescein diacetate increased under elevated CO2 in combination with Cd stress; only cellulase activity decreased. Bacterial abundance in rhizosphere soil was stimulated by elevated CO2 at low Cd concentrations (1.31-5.31 mg Cd kg(-1) dry soil). Actinomycetes, total microbial abundance, and fungi decreased under the combined conditions at 5.31-10.31 mg Cd kg(-1) dry soil. In conclusion, increased production of soluble sugars, total sugars, and proteins in wheat seedlings under elevated CO2 + Cd stress led to greater quantities of organic compounds in the rhizosphere soil relative to seedlings grown under Cd stress only. Elevated CO2 concentrations could moderate the effects of heavy metal pollution on enzyme activity and microorganism abundance in rhizosphere soils, thus improving soil fertility and the microecological rhizosphere environment of wheat under Cd stress.

Outcome of Childhood Acute Lymphoblastic Leukaemia after Induction Therapy --- Three-Year Experience in a Tertiary Care Hospital in Bangladesh

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M Belayet Hossain

2017-01-01

Full Text Available Background: The incidence of different malignancies is increasing among the world populations. Acute lymphoblastic leukaemia (ALL is the most common of all the paediatric malignancies. Response to induction therapy is one of the most important predictors of long term outcome of ALL. Objective: To see the immediate outcome of paediatric ALL patients following induction therapy. Materials and Methods: This retrospective study was conducted from January 2013 to December 2015. Total 221 paediatric ALL patients were included in this study. Diagnosis was based on history, examination, blast cells count on peripheral blood film and bone marrow study, CSF study and immunophenotyping of peripheral blood/bone marrow aspirate in patients who were financially capable. Among them, parents of 40 (18% patients did not agree to start chemotherapy. According to Modified UK ALL 2003 protocol (Regimen A & B 181 patients were given induction therapy (vincristine, prednisolone, L-asparaginase, and daunomycin in high risk patients. Among them 14 patients discontinued, 10 patients died during chemotherapy and rest 157 patients completed induction phase. Bone marrow study was repeated after completion of induction therapy and remission pattern was seen. Results: Out of 157 chemotherapy completed patients, 137 (87% went into complete remission (25% blast cells in the bone marrow. Ten (5.5% patients died due to bleeding, febrile neutropenia and sepsis during the course of induction therapy. Conclusion: ALL in children is curable with effective chemotherapy. Poverty, ignorance and misconception regarding outcome are responsible for refusal and discontinuation of chemotherapy in third world countries like Bangladesh. Mortality and treatment cost can be reduced with the improvement of the facilities for isolation, barrier nursing and supportive treatment, and by creating awareness.

Clinical characteristics of Japanese patients with severe hypertriglyceridemia.

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Tada, Hayato; Kawashiri, Masa-Aki; Nakahashi, Takuya; Yagi, Kunimasa; Chujo, Daisuke; Ohbatake, Azusa; Mori, Yukiko; Mori, Shunsuke; Kometani, Mitsuhiro; Fujii, Hiroshi; Nohara, Atsushi; Inazu, Akihiro; Mabuchi, Hiroshi; Yamagishi, Masakazu; Hayashi, Kenshi

2015-01-01

Although of interest, few data exist on the clinical characteristics of Japanese patients with an extremely high triglyceride level (≥ 1000 mg/dL). We assessed the clinical characteristics of Japanese patients with an extremely high triglyceride level. We investigated the presence of coronary artery disease, history of pancreatitis, the presence of fatty liver, and the potential causes of elevated triglyceride in Japanese subjects with an extremely high level of fasting triglyceride (≥ 1000 mg/dL) among 70,368 subjects whose serum triglyceride was measured for any reason at Kanazawa University Hospital from April 2004 to March 2014. We identified 215 (0.31%) subjects (mean age, 46 years; male, 170, mean body mass index, 25 kg/m(2)) with severe hypertriglyceridemia. Among them, 4 (1.9%) subjects were classified as type I, 97 (45.1%) subjects were type IV, and 114 (53.0%) subjects were type V hyperlipidemia, according to Fredrickson's classification. Among 215 subjects, 116 subjects (54.0%) drank alcohol, 58 (27.0%) showed heavy intake (≥ 60 g/d), and 64 (29.8%) subjects had diabetes. In total, 59 (27.4%) subjects had transient severe hypertriglyceridemia caused by corticosteroids (N = 19), antidepressant (N = 18), l-asparaginase and steroids for acute lymphoid leukemia (N = 15), hormone replacement therapy for breast cancer (N = 9), β-blocker (N = 5), hypothyroidism (N = 4), pregnancy (N = 4), and panhypopituitarism (N = 2). As many as 119 (55.3%) subjects exhibited fatty liver. Moreover, 12 (5.6%) and 17 (7.9%) subjects had a history of pancreatitis and coronary artery disease, respectively. A variety of situations can cause severe hypertriglyceridemia. We suggest that potential secondary causes should be carefully assessed for such patients. Copyright © 2015 National Lipid Association. Published by Elsevier Inc. All rights reserved.

Arginase treatment prevents the recovery of canine lymphoma and osteosarcoma cells resistant to the toxic effects of prolonged arginine deprivation.

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James W Wells

Full Text Available Rapidly growing tumor cells require a nutrient-rich environment in order to thrive, therefore, restricting access to certain key amino acids, such as arginine, often results in the death of malignant cells, which frequently display defective cell cycle check-point control. Healthy cells, by contrast, become quiescent and remain viable under arginine restriction, displaying full recovery upon return to arginine-rich conditions. The use of arginase therapy to restrict available arginine for selectively targeting malignant cells is currently under investigation in human clinical trials. However, the suitability of this approach for veterinary uses is unexplored. As a prelude to in vivo studies in canine malignancies, we examined the in vitro effects of arginine-deprivation on canine lymphoid and osteosarcoma cell lines. Two lymphoid and 2 osteosarcoma cell lines were unable to recover following 6 days of arginine deprivation, but all remaining cell lines displayed full recovery upon return to arginine-rich culture conditions. These remaining cell lines all proved susceptible to cell death following the addition of arginase to the cultures. The lymphoid lines were particularly sensitive to arginase, becoming unrecoverable after just 3 days of treatment. Two of the osteosarcoma lines were also susceptible over this time-frame; however the other 3 lines required 6-8 days of arginase treatment to prevent recovery. In contrast, adult progenitor cells from the bone marrow of a healthy dog were able to recover fully following 9 days of culture in arginase. Over 3 days in culture, arginase was more effective than asparaginase in inducing the death of lymphoid lines. These results strongly suggest that short-term arginase treatment warrants further investigation as a therapy for lymphoid malignancies and osteosarcomas in dogs.

Acute lymphoblastic leukemia in very young children. Diagnostic and therapeutic aspects of 43 cases

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Leverger, G.; Bancillon, A.; Schaison, G.; Alby, N.; Boiron, M.

1986-01-01

Between 1974 and 1982, 43 children less than 2 years of age were treated in the hematology department of Hospital Saint-Louis for acute lymphoblastic leukemia (ALL). Of the patients who presented before 18 months of age, 80% had a WBC greater than 100,000 microliter and/or a great tumor bulk. As a result of our experience, treatment regimens have been changed here from conventional chemotherapy to a very intensive program with a heavy induction (vincristine, daunorubicin, cyclophosphamide, prednisone, and L-asparaginase) and monthly reinductions with the same drugs plus ArA-C, without maintenance. Prophylaxis included CNS irradiation (16-24 Gy) after 12 months of age, plus intrathecal methotrexate. Complete remission (CR) occurred in 78% before 18 months and in 100% between 18 and 24 months of age at diagnosis. In this report the probability of a prolonged CR (33% at 2 years) was the same before and after 12 months of age. However, younger patients were more intensively treated. The prognosis for children less than 1 year of age who received very intensive chemotherapy has greatly improved, with a significantly higher probability of long CR (p less than 0.02). Presently, 10 of 43 children are in CR 27 months to 8 years after diagnosis. Of 18 patients aged less than 1 year at diagnosis, four are in CR. No relapse occurred after 23 months. None of these patients presented with important sequellae, with the exception of one child who suffered from severe bacterial meningitis. An aggressive chemotherapy program is indicated in patients less than 2 years of age. The feasibility of this mode of treatment in young patients is possible only with the help of specific supportive care

Harnessing natural diversity to probe metabolic pathways.

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Oliver R Homann

2005-12-01

Full Text Available Analyses of cellular processes in the yeast Saccharomyces cerevisiae rely primarily upon a small number of highly domesticated laboratory strains, leaving the extensive natural genetic diversity of the model organism largely unexplored and unexploited. We asked if this diversity could be used to enrich our understanding of basic biological processes. As a test case, we examined a simple trait: the utilization of di/tripeptides as nitrogen sources. The capacity to import small peptides is likely to be under opposing selective pressures (nutrient utilization versus toxin vulnerability and may therefore be sculpted by diverse pathways and strategies. Hitherto, dipeptide utilization in S. cerevisiae was solely ascribed to the activity of a single protein, the Ptr2p transporter. Using high-throughput phenotyping and several genetically diverse strains, we identified previously unknown cellular activities that contribute to this trait. We find that the Dal5p allantoate/ureidosuccinate permease is also capable of facilitating di/tripeptide transport. Moreover, even in the absence of Dal5p and Ptr2p, an additional activity--almost certainly the periplasmic asparaginase II Asp3p--facilitates the utilization of dipeptides with C-terminal asparagine residues by a different strategy. Another, as-yet-unidentified activity enables the utilization of dipeptides with C-terminal arginine residues. The relative contributions of these activities to the utilization of di/tripeptides vary among the strains analyzed, as does the vulnerability of these strains to a toxic dipeptide. Only by sampling the genetic diversity of multiple strains were we able to uncover several previously unrecognized layers of complexity in this metabolic pathway. High-throughput phenotyping facilitates the rapid exploration of the molecular basis of biological complexity, allowing for future detailed investigation of the selective pressures that drive microbial evolution.

Acute lymphoblastic leukemia in very young children. Diagnostic and therapeutic aspects of 43 cases

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Leverger, G.; Bancillon, A.; Schaison, G.; Alby, N.; Boiron, M.

Between 1974 and 1982, 43 children less than 2 years of age were treated in the hematology department of Hospital Saint-Louis for acute lymphoblastic leukemia (ALL). Of the patients who presented before 18 months of age, 80% had a WBC greater than 100,000 microliter and/or a great tumor bulk. As a result of our experience, treatment regimens have been changed here from conventional chemotherapy to a very intensive program with a heavy induction (vincristine, daunorubicin, cyclophosphamide, prednisone, and L-asparaginase) and monthly reinductions with the same drugs plus ArA-C, without maintenance. Prophylaxis included CNS irradiation (16-24 Gy) after 12 months of age, plus intrathecal methotrexate. Complete remission (CR) occurred in 78% before 18 months and in 100% between 18 and 24 months of age at diagnosis. In this report the probability of a prolonged CR (33% at 2 years) was the same before and after 12 months of age. However, younger patients were more intensively treated. The prognosis for children less than 1 year of age who received very intensive chemotherapy has greatly improved, with a significantly higher probability of long CR (p less than 0.02). Presently, 10 of 43 children are in CR 27 months to 8 years after diagnosis. Of 18 patients aged less than 1 year at diagnosis, four are in CR. No relapse occurred after 23 months. None of these patients presented with important sequellae, with the exception of one child who suffered from severe bacterial meningitis. An aggressive chemotherapy program is indicated in patients less than 2 years of age. The feasibility of this mode of treatment in young patients is possible only with the help of specific supportive care.

Evaluation of certain food additives.

Science.gov (United States)

2009-01-01

This report represents the conclusions of a Joint FAO/WHO Expert Committee convened to evaluate the safety of various food additives, including flavouring agents, with a view to recommending acceptable daily intakes (ADIs) and to preparing specifications for identity and purity. The first part of the report contains a general discussion of the principles governing the toxicological evaluation and assessment of intake of food additives (in particular, flavouring agents). A summary follows of the Committee's evaluations of technical, toxicological and intake data for certain food additives (asparaginase from Aspergillus niger expressed in A. niger, calcium lignosulfonate (40-65), ethyl lauroyl arginate, paprika extract, phospholipase C expressed in Pichia pastoris, phytosterols, phytostanols and their esters, polydimethylsiloxane, steviol glycosides and sulfites [assessment of dietary exposure]) and 10 groups of related flavouring agents (aliphatic branched-chain saturated and unsaturated alcohols, aldehydes, acids and related esters; aliphatic linear alpha,beta-unsaturated aldehydes, acids and related alcohols, acetals and esters; aliphatic secondary alcohols, ketones and related esters; alkoxy-substituted allylbenzenes present in foods and essential oils and used as flavouring agents; esters of aliphatic acyclic primary alcohols with aliphatic linear saturated carboxylic acids; furan-substituted aliphatic hydrocarbons, alcohols, aldehydes, ketones, carboxylic acids and related esters, sulfides, disulfides and ethers; miscellaneous nitrogen-containing substances; monocyclic and bicyclic secondary alcohols, ketones and related esters; hydroxy- and alkoxy-substituted benzyl derivatives; and substances structurally related to menthol). Specifications for the following food additives were revised: canthaxanthin; carob bean gum and carob bean gum (clarified); chlorophyllin copper complexes, sodium and potassium salts; Fast Green FCF; guar gum and guar gum (clarified

Anti-leukemic activity of bortezomib and carfilzomib on B-cell precursor ALL cell lines.

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Kazuya Takahashi

Full Text Available Prognosis of childhood acute lymphoblastic leukemia (ALL has been dramatically improved. However, prognosis of the cases refractory to primary therapy is still poor. Recent phase 2 study on the efficacy of combination chemotherapy with bortezomib (BTZ, a proteasome inhibitor, for refractory childhood ALL demonstrated favorable clinical outcomes. However, septic death was observed in over 10% of patients, indicating the necessity of biomarkers that could predict BTZ sensitivity. We investigated in vitro BTZ sensitivity in a large panel of ALL cell lines that acted as a model system for refractory ALL, and found that Philadelphia chromosome-positive (Ph+ ALL, IKZF1 deletion, and biallelic loss of CDKN2A were associated with favorable response. Even in Ph-negative ALL cell lines, IKZF1 deletion and bilallelic loss of CDKN2A were independently associated with higher BTZ sensitivity. BTZ showed only marginal cross-resistance to four representative chemotherapeutic agents (vincristine, dexamethasone, l-asparaginase, and daunorubicin in B-cell precursor-ALL cell lines. To improve the efficacy and safety of proteasome inhibitor combination chemotherapy, we also analyzed the anti-leukemic activity of carfilzomib (CFZ, a second-generation proteasome inhibitor, as a substitute for BTZ. CFZ showed significantly higher activity than BTZ in the majority of ALL cell lines except for the P-glycoprotein-positive t(17;19 ALL cell lines, and IKZF1 deletion was also associated with a favorable response to CFZ treatment. P-glycoprotein inhibitors effectively restored the sensitivity to CFZ, but not BTZ, in P-glycoprotein-positive t(17;19 ALL cell lines. P-glycoprotein overexpressing ALL cell line showed a CFZ-specific resistance, while knockout of P-glycoprotein by genome editing with a CRISPR/Cas9 system sensitized P-glycoprotein-positive t(17;19 ALL cell line to CFZ. These observations suggested that IKZF1 deletion could be a useful biomarker to predict good

Gln3p and Nil1p regulation of invertase activity and SUC2 expression in Saccharomyces cerevisiae.

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Oliveira, Edna Maria Morais; Mansure, José João; Bon, Elba Pinto da Silva

2005-04-01

In Saccharomyces cerevisiae, sensing and signalling pathways regulate gene expression in response to quality of carbon and nitrogen sources. One such system, the target of rapamycin (Tor) proteins, senses nutrients and uses the GATA activators Gln3p and Nil1p to regulate translation in response to low-quality carbon and nitrogen. The signal transduction, triggered in response to nitrogen nutrition that is sensed by the Tor proteins, operates via a regulatory pathway involving the cytoplasmic factor Ure2p. When carbon and nitrogen are abundant, the phosphorylated Ure2p anchors the also phosphorylated Gln3p and Nil1p in the cytoplasm. Upon a shift from high- to low-quality nitrogen or treatment with rapamycin all three proteins are dephosphorylated, causing Gln3p and Nil1p to enter the nucleus and promote transcription. The genes that code for yeast periplasmic enzymes with nutritional roles would be obvious targets for regulation by the sensing and signalling pathways that respond to quality of carbon and nitrogen sources. Indeed, previous results from our laboratory had shown that the GATA factors Gln3p, Nil1p, Dal80p, Nil2p and also the protein Ure2 regulate the expression of asparaginase II, coded by ASP3. We also had observed that the activity levels of the also periplasmic invertase, coded by SUC2, were 6-fold lower in ure2 mutant cells in comparison to wild-type cells collected at stationary phase. These results suggested similarities between the signalling pathways regulating the expression of ASP3 and SUC2. In the present work we showed that invertase levels displayed by the single nil1 and gln3 and by the double gln3nil1 mutant cells, cultivated in a sucrose-ammonium medium and collected at the exponential phase, were 6-, 10- and 60-fold higher, respectively, in comparison to their wild-type counterparts. RT-PCR data of SUC2 expression in the double-mutant cells indicated a 10-fold increase in the mRNA(SUC2) levels.

Novel Immunotherapy Options for Extranodal NK/T-Cell Lymphoma

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Boyu Hu

2018-04-01

Full Text Available Extranodal NK/T-cell lymphoma (ENKTCL is a highly aggressive mature NK/T-cell neoplasm marked by NK-cell phenotypic expression of CD3ε and CD56. While the disease is reported worldwide, there is a significant geographic variation with its highest incidence in East Asian countries possibly related to the frequent early childhood exposure of Epstein–Barr virus (EBV and specific ethnic–genetical background, which contributes to the tumorigenesis. Historically, anthracycline-based chemotherapy such as CHOP (cyclophosphamide, adriamycin, vincristine, and prednisone was used, but resulted in poor outcomes. This is due in part to intrinsic ENKTCL resistance to anthracycline caused by high expression levels of P-glycoprotein. The recent application of combined modality therapy with concurrent or sequential radiation therapy for early stage disease, along with non-anthracycline-based chemotherapy regimens consisting of drugs independent of P-glycoprotein have significantly improved clinical outcomes. Particularly, this neoplasm shows high sensitivity to l-asparaginase as NK-cells lack asparagine synthase activity. Even still, outcomes of patients with advanced stage disease or those with relapsed/recurrent disease are dismal with overall survival of generally a few months. Thus, novel therapies are needed for this population. Clinical activity of targeted antibodies along with antibody–drug conjugates, such as daratumumab (naked anti-CD38 antibody and brentuximab vedotin (anti-CD30 antibody conjugated with auristatin E, have been reported. Further promising data have been shown with checkpoint inhibitors as high levels of programmed death-ligand 1 expression are observed in ENKTCL due to EBV-driven overexpression of the latent membrane proteins [latent membrane protein 1 (LMP1 and LMP2] with activation of the NF-κB/MAPK pathways. Initial case series with programmed death 1 inhibitors showed an overall response rate of 100% in seven relapsed

A Cyanide-Induced 3-Cyanoalanine Nitrilase in the Cyanide-Assimilating Bacterium Pseudomonas pseudoalcaligenes Strain CECT 5344.

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Acera, Felipe; Carmona, María Isabel; Castillo, Francisco; Quesada, Alberto; Blasco, Rafael

2017-05-01

Pseudomonas pseudoalcaligenes CECT 5344 is a bacterium able to assimilate cyanide as a sole nitrogen source. Under this growth condition, a 3-cyanoalanine nitrilase enzymatic activity was induced. This activity was encoded by nit4 , one of the four nitrilase genes detected in the genome of this bacterium, and its expression in Escherichia coli enabled the recombinant strain to fully assimilate 3-cyanoalanine. P. pseudoalcaligenes CECT 5344 showed a weak growth level with 3-cyanoalanine as the N source, unless KCN was also added. Moreover, a nit4 knockout mutant of P. pseudoalcaligenes CECT 5344 became severely impaired in its ability to grow with 3-cyanoalanine and cyanide as nitrogen sources. The native enzyme expressed in E. coli was purified up to electrophoretic homogeneity and biochemically characterized. Nit4 seems to be specific for 3-cyanoalanine, and the amount of ammonium derived from the enzymatic activity doubled in the presence of exogenously added asparaginase activity, which demonstrated that the Nit4 enzyme had both 3-cyanoalanine nitrilase and hydratase activities. The nit4 gene is located downstream of the cyanide resistance transcriptional unit containing cio1 genes, whose expression levels are under the positive control of cyanide. Real-time PCR experiments revealed that nit4 expression was also positively regulated by cyanide in both minimal and LB media. These results suggest that this gene cluster including cio1 and nit4 could be involved both in cyanide resistance and in its assimilation by P. pseudoalcaligenes CECT 5344. IMPORTANCE Cyanide is a highly toxic molecule present in some industrial wastes due to its application in several manufacturing processes, such as gold mining and the electroplating industry. The biodegradation of cyanide from contaminated wastes could be an attractive alternative to physicochemical treatment. P. pseudoalcaligenes CECT 5344 is a bacterial strain able to assimilate cyanide under alkaline conditions, thus

Treatment reduction for children and young adults with low-risk acute lymphoblastic leukaemia defined by minimal residual disease (UKALL 2003): a randomised controlled trial.

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Vora, Ajay; Goulden, Nick; Wade, Rachel; Mitchell, Chris; Hancock, Jeremy; Hough, Rachael; Rowntree, Clare; Richards, Sue

2013-03-01

Minimal residual disease (MRD) is the most sensitive and specific predictor of relapse risk in children with acute lymphoblastic leukaemia (ALL) during remission. We assessed whether treatment intensity could be adjusted for children and young adults according to MRD risk stratification. Between Oct 1, 2003 and June 30, 2011, consecutive children and young adults (aged 1-25 years) with ALL from the UK and Ireland were recruited. Eligible patients were categorised into clinical standard, intermediate, and high risk groups on the basis of a combination of National Cancer Institute (NCI) criteria, cytogenetics, and early response to induction therapy, which was assessed by bone marrow blast counts taken at days 8 (NCI high-risk patients) and 15 (NCI standard-risk patients) after induction began. Clinical standard-risk and intermediate-risk patients were assessed for MRD. Those classified as MRD low risk (undetectable MRD at the end of induction [day 29] or detectable MRD at day 29 that became undetectable by week 11) were randomly assigned to receive one or two delayed intensification courses. Patients had received induction, consolidation, and interim maintenance therapy before they began delayed intensification. Delayed intensification consisted of pegylated asparaginase on day 4; vincristine, dexamethasone (alternate weeks), and doxorubicin for 3 weeks; and 4 weeks of cyclophosphamide and cytarabine. Computer randomisation was done with stratification by MRD result and balancing for sex, age, and white blood cell count at diagnosis by method of minimisation. Patients, clinicians, and data analysts were not masked to treatment allocation. The primary outcome was event-free survival (EFS), which was defined as time to relapse, secondary tumour, or death. Our aim was to rule out a 7% reduction in EFS in the group given one delayed intensification course relative to that given two delayed intensification courses. Analyses were by intention to treat. This trial is

IL-7 Receptor Mutations and Steroid Resistance in Pediatric T cell Acute Lymphoblastic Leukemia: A Genome Sequencing Study.

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Yunlei Li

2016-12-01

-type and mutant IL7R signaling molecules in two steroid-sensitive T-ALL cell lines (SUPT1 and P12 Ichikawa cells using inducible lentiviral expression constructs. We found that expressing mutant IL7R, JAK1, or NRAS, or wild-type NRAS or AKT, specifically induced steroid resistance without affecting sensitivity to vincristine or L-asparaginase. In contrast, wild-type IL7R, JAK1, and JAK3, as well as mutant JAK3 and mutant AKT, had no effect. We then performed a functional study to examine the mechanisms underlying steroid resistance and found that, rather than changing the steroid receptor's ability to activate downstream targets, steroid resistance was associated with strong activation of MEK-ERK and AKT, downstream components of the IL7R signaling pathway, thereby inducing a robust antiapoptotic response by upregulating MCL1 and BCLXL expression. Both the MEK-ERK and AKT pathways also inactivate BIM, an essential molecule for steroid-induced cell death, and inhibit GSK3B, an important regulator of proapoptotic BIM. Importantly, treating our cell lines with IL7R signaling inhibitors restored steroid sensitivity. To address clinical relevance, we treated primary T-ALL cells obtained from 11 patients with steroids either alone or in combination with IL7R signaling inhibitors; we found that including a MEK, AKT, mTOR, or dual PI3K/mTOR inhibitor strongly increased steroid-induced cell death. Therefore, combining these inhibitors with steroid treatment may enhance steroid sensitivity in patients with ALL. The main limitation of our study was the modest cohort size, owing to the very low incidence of T-ALL.Using an unbiased sequencing approach, we found that specific mutations in IL7R signaling molecules underlie steroid resistance in T-ALL. Future prospective clinical studies should test the ability of inhibitors of MEK, AKT, mTOR, or PI3K/mTOR to restore or enhance steroid sensitivity and improve clinical outcome.

IL-7 Receptor Mutations and Steroid Resistance in Pediatric T cell Acute Lymphoblastic Leukemia: A Genome Sequencing Study

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Stubbs, Andrew P.; Vroegindeweij, Eric M.; Smits, Willem K.; van Marion, Ronald; Dinjens, Winand N. M.; Horstmann, Martin; Kuiper, Roland P.; Zaman, Guido J. R.; van der Spek, Peter J.; Pieters, Rob; Meijerink, Jules P. P.

2016-01-01

expressed wild-type and mutant IL7R signaling molecules in two steroid-sensitive T-ALL cell lines (SUPT1 and P12 Ichikawa cells) using inducible lentiviral expression constructs. We found that expressing mutant IL7R, JAK1, or NRAS, or wild-type NRAS or AKT, specifically induced steroid resistance without affecting sensitivity to vincristine or L-asparaginase. In contrast, wild-type IL7R, JAK1, and JAK3, as well as mutant JAK3 and mutant AKT, had no effect. We then performed a functional study to examine the mechanisms underlying steroid resistance and found that, rather than changing the steroid receptor’s ability to activate downstream targets, steroid resistance was associated with strong activation of MEK-ERK and AKT, downstream components of the IL7R signaling pathway, thereby inducing a robust antiapoptotic response by upregulating MCL1 and BCLXL expression. Both the MEK-ERK and AKT pathways also inactivate BIM, an essential molecule for steroid-induced cell death, and inhibit GSK3B, an important regulator of proapoptotic BIM. Importantly, treating our cell lines with IL7R signaling inhibitors restored steroid sensitivity. To address clinical relevance, we treated primary T-ALL cells obtained from 11 patients with steroids either alone or in combination with IL7R signaling inhibitors; we found that including a MEK, AKT, mTOR, or dual PI3K/mTOR inhibitor strongly increased steroid-induced cell death. Therefore, combining these inhibitors with steroid treatment may enhance steroid sensitivity in patients with ALL. The main limitation of our study was the modest cohort size, owing to the very low incidence of T-ALL. Conclusions Using an unbiased sequencing approach, we found that specific mutations in IL7R signaling molecules underlie steroid resistance in T-ALL. Future prospective clinical studies should test the ability of inhibitors of MEK, AKT, mTOR, or PI3K/mTOR to restore or enhance steroid sensitivity and improve clinical outcome. PMID:27997540