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The interest in plant-derived virus-like particles (pVLPs) for the design of a new generation of nanocarriers is based on their lack of infection for humans, their immunostimulatory properties to fight cancer cells, and their capability to contain and release cargo molecules. Asparaginase (ASNase) is an FDA-approved drug to treat acute lymphoblastic leukemia (LLA); however, it exhibits high immunogenicity which often leads to discontinuation of treatment. In previous work, we encapsulated ASNase into bacteriophage P22-based VLPs through genetic-directed design to form the ASNase-P22 nanobioreactors. In this work, a commercial ASNase was encapsulated into brome mosaic virus-like particles (BMV-VLPs) to form stable ASNase-BMV nanobioreactors. According to our results, we observed that ASNase-BMV nanobioreactors had similar cytotoxicity against MOLT-4 and Reh cells as the commercial drug. In vivo assays showed a higher specific anti-ASNase IgG response in BALB/c mice immunized with ASNase encapsulated into BMV-VLPs compared with those immunized with free ASNase. Nevertheless, we also detected a high and specific IgG response against BMV capsids on both ASNase-filled capsids (ASNase-BMV) and empty BMV capsids. Despite the fact that our in vivo studies showed that the BMV-VLPs stimulate the immune response either empty or with cargo proteins, the specific cytotoxicity against leukemic cells allows us to propose ASNase-BMV as a potential novel formulation for LLA treatment where in vitro and in vivo evidence of functionality is provided. [ABSTRACT FROM AUTHOR]

Amino acid availability is crucial for cancer cells' survivability. Leukemia and colorectal cancer cells have been shown to resist asparagine depletion by utilizing GSK3-dependent proteasomal degradation, termed the Wnt-dependent stabilization of proteins (Wnt/STOP), to replenish their amino acid pool. The inhibition of GSK3α halts the sourcing of amino acids, which subsequently leads to cancer cell vulnerability toward asparaginase therapy. However, resistance toward GSK3α-mediated protein breakdown can occur, whose underlying mechanism is poorly understood. Here, we set out to define the mechanisms driving dependence toward this degradation machinery upon asparagine starvation in cancer cells. We show the independence of known stress response pathways including the integrated stress response mediated with GCN2. Additionally, we demonstrate the independence of changes in cell cycle progression and expression levels of the asparagine-synthesizing enzyme ASNS. Instead, RNA sequencing revealed that GSK3α inhibition and asparagine starvation leads to the temporally dynamic downregulation of distinct ribosomal proteins, which have been shown to display anti-proliferative functions. Using a CRISPR/Cas9 viability screen, we demonstrate that the downregulation of these specific ribosomal proteins can rescue cell death upon GSK3α inhibition and asparagine starvation. Thus, our findings suggest the vital role of the previously unrecognized regulation of ribosomal proteins in bridging GSK3α activity and tolerance of asparagine starvation. [ABSTRACT FROM AUTHOR]

L-asparaginase (L-ASNase) is a versatile anticancer and acrylamide reducing enzyme used in medical and food industries. Exploration of new sources of L-asparaginase is in demand due to immunogenic issues, short half-life and narrow range of pH and temperature stability of available formulations. The present study describes extracellular Type II L-ASNase production from soil Bacillus licheniformis ASN51 strain. Optimized asparaginase production with a specific activity of 499 U mg-1 was obtained at pH 8 and 37ºC in M9 medium containing 0.2% glucose and 1% L-asparagine. L-ASNase was precipitated using acetone and purified through Sephadex G-100 column yielding 61.2 and 34% recovery, respectively. The purified asparaginase has a molecular mass of 38 kDa and specific activity of 8,333 U mg-1. L-ASNase showed stability at a wide range of pH (4-9) and temperature (10-50ºC) while retained 100% of its activity for 24 h at 37ºC, pH 7. Enzyme kinetics revealed a Vmax of 7750 U and Km of 0.04 mM. Purified L-ASNase from B. licheniformis ASN51 showed antioxidant activity (IC50 value 53.1 µg mL-1) against 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical and anticancer activity (53.3%) against HepG2 cell line. To the best of knowledge, among reported strains of B. licheniformis, ASN51 is the highest asparaginase producing strain. Purified L-ASNase showed long-term stability at physiological pH and temperature indicating its suitability for therapeutic applications. [ABSTRACT FROM AUTHOR]

Sea buckthorn pomace is a by-product of juice production, which is still rich in bioactive compounds. After drying, the pomace can be effectively used as a valuable addition to bakery products supporting their nutritional value. However, due to the high content of the amino acid asparagine in sea buckthorn, this promising material contributes to the undesirable formation of acrylamide. To reduce the risk from this potentially carcinogenic compound, enzymatic treatment of sea buckthorn with asparaginase was applied, which resulted in a substantial reduction of asparagine content from 1834 mg/kg in untreated dried sea buckthorn pomace to 89 mg/kg in enzymatically treated dried sea buckthorn pomace. 10% substitution of wholegrain cereal flour with enzymatically treated sea buckthorn pomace powder in rye and triticale biscuits resulted in a 35% reduction in acrylamide content, in the case of wholegrain wheat biscuits up to a 64% reduction, compared to biscuits with untreated sea buckthorn pomace powder. This study confirmed that treating fruit with asparaginase is an effective way to reduce health risk caused by acrylamide in biscuits enriched with nutritionally valuable fruit pomace. [ABSTRACT FROM AUTHOR]

Mitochondrial respiration is critical for cell proliferation. In addition to producing ATP, respiration generates biosynthetic precursors, such as aspartate, an essential substrate for nucleotide synthesis. Here, we show that in addition to depleting intracellular aspartate, electron transport chain (ETC) inhibition depletes aspartate-derived asparagine, increases ATF4 levels, and impairs mTOR complex I (mTORC1) activity. Exogenous asparagine restores proliferation, ATF4 and mTORC1 activities, and mTORC1-dependent nucleotide synthesis in the context of ETC inhibition, suggesting that asparagine communicates active respiration to ATF4 and mTORC1. Finally, we show that combination of the ETC inhibitor metformin, which limits tumor asparagine synthesis, and either asparaginase or dietary asparagine restriction, which limit tumor asparagine consumption, effectively impairs tumor growth in multiple mouse models of cancer. Because environmental asparagine is sufficient to restore tumor growth in the context of respiration impairment, our findings suggest that asparagine synthesis is a fundamental purpose of tumor mitochondrial respiration, which can be harnessed for therapeutic benefit to cancer patients.

L-Asparaginase is one of the main chemotherapy regiments for acute lymphocytic leukemia (ALL) management. Acute pancreatitis is one of the serious side effects of l-asparaginase administration and may lead to interruption of chemotherapy cycle. Long term complications may be devastating for patients which include of pseudocyst pancreas and chronic pancreatitis. Asparaginase induced pancreatitis is rare among adult due to the nature of ALL which commonly occurred in children population. The pathophysiology of asparaginase induced pancreatitis is still unclear. Here we present 18-year-old male with ALL and asparaginase induced acute necrotizing pancreatitis which complicated to chronic pancreatitis and pseudocyst.

Paediatric regimens which incorporate asparaginase have improved outcomes of adolescents and younger adults with acute lymphoblastic leukaemia but are limited by toxicity. This retrospective report by Tinajero and Xu suggests that delaying the timing of asparaginase administration during ALL induction may reduce risk of hepatotoxicity.Commentary on: Tinajero et al. Delaying pegaspargase during induction in adults with acute lymphoblastic leukaemia is associated with lower risk of high‐grade hepatotoxicity without adversely impacting outcomes. Br J Haematol 2024 (Online ahead of print). doi: 10.1111/bjh.19880. [ABSTRACT FROM AUTHOR]

The first article discusses the role of TRPV4 in the production of interleukin 10 (IL-10) during inflammation. The researchers found that TRPV4 activation increased IL-10 production in lung tissue, but did not play a role in resolving inflammation. They also discovered that the transcription factor CREB mediates the production of IL-10. The researchers further investigated the effect of the TRPV4-CREB-IL-10 pathway on mitochondrial health and found that IL-10 has a protective role in maintaining mitochondrial health in macrophages during inflammation.The second article explores the potential use of asparaginase, an enzyme that hydrolyzes asparagine, in cancer treatment. Cancer cells rely on asparagine from the blood to survive and proliferate, so starving them of asparagine can cause them to die. The researchers searched for asparaginase without glutaminase activity among commensal bacteria in the mouth and intestinal tract. They identified bacteria that produce asparaginase without glutaminase activity, which could potentially be used as a treatment for certain cancers.The third article investigates the use of seaweed-derived iron nanoparticles for cancer treatment. The researchers extracted an aqueous extract of a brown seaweed and mixed it with ferric chloride and sodium hydroxide to form stable iron nanoparticles. These nanoparticles showed potential for photocatalytic applications and were effective against liver and pancreatic cancer cells in vitro. Further research is needed to explore their [Extracted from the article]

On the occasion of the 20th anniversary of the discovery of acrylamide in food, an analysis of patents related to the mitigation of this compound in food products obtained through immersion frying was carried out. For this purpose, a comprehensive search, compilation, and information analysis were conducted using free online databases such as Google Patents, Patenscope, and Lens. The search yielded a total of 79 patents within the considered time period (2002-2022). The countries with the highest number of granted patents were the United States, the European Union, and South Korea. The patents were classified into four main approaches: raw material modification (49%), application of pre-treatments (27%), process modification (16%), and measurement techniques (8%). Among the results, Frito-Lay, an American company, stands out as the food industry company with the highest number of granted patents, totaling 15. Based on this review, it is concluded that while a significant number of patents have been granted in recent years, there is still a lag in developing countries. Furthermore, more studies are needed to determine acrylamide in starchy food matrices subjected to immersion frying different from potatoes.

Background: Among malignant diseases which develop during childhood, hematological cancers, such as leukemias and lymphomas, are the most common. Outcomes have greatly improved due to the refinement of multiagent chemotherapy regimens that include enhanced asparaginase therapy. In this study, we aimed to evaluate our experiences related to the analytical and clinical significance of determining l-Asparaginase activity. Methods: Since 2016, the Laboratory of the Children’s Hospital Zagreb has routinely measured l-Asparaginase activity and to date, has measured more than 280 examples of activity in a total of 57 children with hematological malignancy treated at the Pediatric Oncology Department of the Children’s Hospital Zagreb. Three asparaginase products were available: native E. colil-Asparaginase; a pegylated form of this enzyme; and a native product from Erwinia chrysanthemi. A retrospective data analysis was performed. Results: Out of the fifty-seven children, seven had an allergic reaction (12.3%), five (8.8%) had silent inactivation, and seven (12.3%) developed acute pancreatitis. Allergic reactions and silent inactivation were more common in children treated with native E. colil-Asparaginase, while pancreatitis was more common in children treated with the pegylated form. Conclusions: The monitoring of l-Asparaginase activity may help to optimize therapy by identifying patients with ‘silent inactivation’, and/or by dose correction when l-Asparaginase activity is too high (slow elimination).

On the occasion of the 20th anniversary of the discovery of acrylamide in food, an analysis of patents related to the mitigation of this compound in food products obtained through immersion frying was carried out. For this purpose, a comprehensive search, compilation, and information analysis were conducted using free online databases such as Google Patents, Patenscope, and Lens. The search yielded a total of 79 patents within the considered time period (2002-2022). The countries with the highest number of granted patents were the United States, the European Union, and South Korea. The patents were classified into four main approaches: raw material modification (49%), application of pre-treatments (27%), process modification (16%), and measurement techniques (8%). Among the results, Frito-Lay, an American company, stands out as the food industry company with the highest number of granted patents, totaling 15. Based on this review, it is concluded that while a significant number of patents have been granted in recent years, there is still a lag in developing countries. Furthermore, more studies are needed to determine acrylamide in starchy food matrices subjected to immersion frying different from potatoes.

Abstract The food enzyme asparaginase (l‐asparagine amidohydrolase, EC 3.5.1.1) is produced with the genetically modified Aspergillus oryzae strain NZYM‐SP by Novozymes A/S. The genetic modifications do not give rise to safety concerns. The food enzyme is considered free from viable cells of the production organism and its DNA. It is intended to be used to prevent acrylamide formation in food processing. Dietary exposure to the food enzyme–total organic solids (TOS) was estimated to be up to 0.101 mg TOS/kg body weight (bw) per day in European populations. Genotoxicity tests did not indicate a safety concern. The systemic toxicity was assessed by means of a repeated dose 90‐day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 880 mg TOS/kg bw per day, the highest dose tested, which, when compared with the estimated dietary exposure, resulted in a margin of exposure of at least 8,713. A search for the similarity of the amino acid sequence of the food enzyme to known allergens was made and no match was found. The Panel considered that a risk of allergic reactions by dietary exposure cannot be excluded, but the likelihood is low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.

Simple Summary: Many types of cancer cells utilize the common amino acid l-glutamine to maintain their metabolic demands for energy and the nitrogen required for DNA synthesis. Versatility to control energy metabolism from l-glutamine (anaplerosis) is promoted by the use of two distinct pathways. The first (pathway 1; the canonical pathway) is as follows: [l-glutamine → l-glutamate ⇆ α-ketoglutarate → tricarboxylic acid (TCA) cycle]. This pathway contrasts with the much less studied GTωA (glutamine transaminase—ω-amidase or glutaminase II) pathway (pathway 2): [l-glutamine ⇆ α-ketoglutaramate (KGM) → α-ketoglutarate → TCA cycle]. Our prior publications have emphasized the importance of regulation of both pathways, which enables cancer cells to maintain selective metabolic advantages and to conserve their reliance on glucose. This review summarizes the metabolic importance of the GTωA pathway in both cancerous and normal tissues and proposes that anti-cancer strategies, based on inhibition of l-glutamine metabolism, require consideration of both the canonical and GTωA pathways. Many cancers utilize l-glutamine as a major energy source. Often cited in the literature as "l-glutamine addiction", this well-characterized pathway involves hydrolysis of l-glutamine by a glutaminase to l-glutamate, followed by oxidative deamination, or transamination, to α-ketoglutarate, which enters the tricarboxylic acid cycle. However, mammalian tissues/cancers possess a rarely mentioned, alternative pathway (the glutaminase II pathway): l-glutamine is transaminated to α-ketoglutaramate (KGM), followed by ω-amidase (ωA)-catalyzed hydrolysis of KGM to α-ketoglutarate. The name glutaminase II may be confused with the glutaminase 2 (GLS2) isozyme. Thus, we recently renamed the glutaminase II pathway the "glutamine transaminase—ω-amidase (GTωA)" pathway. Herein, we summarize the metabolic importance of the GTωA pathway, including its role in closing the methionine salvage pathway, and as a source of anaplerotic α-ketoglutarate. An advantage of the GTωA pathway is that there is no net change in redox status, permitting α-ketoglutarate production during hypoxia, diminishing cellular energy demands. We suggest that the ability to coordinate control of both pathways bestows a metabolic advantage to cancer cells. Finally, we discuss possible benefits of GTωA pathway inhibitors, not only as aids to studying the normal biological roles of the pathway but also as possible useful anticancer agents. [ABSTRACT FROM AUTHOR]

Cereal biscuits are popular snacks of daily usage. Their nutritional value is enhanced if they are produced from wholegrain flour of nutritionally rich cereals and/or contain valuable natural sources of health promoting compounds. In this study, wholegrain flour from wheat, rye, and triticale (hybrid of wheat and rye) were used as a basis for biscuit production and dried sea buckthorn (Hippophae rhamnoides L.) pomace as an additive for enhancement of their nutritional value. Besides nutritional benefits, sea buckthorn pomace addition increased hardness up to 37% and fracturability up to 30%, and moreover, an undesirable acrylamide formation was increased twice in case of wheat and triticale biscuits, and up to 4.5 times in rye biscuits. For diminishing the acrylamide formation, the asparaginase treatment of wet sea buckthorn pomace was applied which resulted in a substantial decrease of acrylamide (30 - 60%) in final biscuits. This intervention was examined in terms of the impact on textural properties of cereal biscuits with sea buckthorn pomace and with enzymatically treated sea buckthorn pomace. Despite expectations of negligible impact on quality properties of biscuits, texture analysis showed significant differences between cereal biscuits containing untreated and enzymatically treated sea buckthorn pomace reflected in a decrease of hardness and fracturability to original values in controls, at least. However, these alterations cannot be fully attributed to an enzymatic treatment of sea buckthorn pomace since the procedure of asparaginase application, including the adjustment of pH to neutral values, affected the properties of this additive. Descriptive sensory analysis and consumer acceptance test revealed significant preferences of triticale and rye biscuits with enzymatically treated sea buckthorn pomace addition. [ABSTRACT FROM AUTHOR]

Pegylated form of E. coli derived asparaginase (PEG) is a crucial component of pediatric ALL therapy. Patients who develop a hypersensitivity (HSR) reaction with PEG receive an alternative form – Erwinia asparaginase (EA). However, an international shortage in 2017 had made it challenging to treat these patients. We have developed a comprehensive strategy to address this need. This is a single center, retrospective analysis. All patients receiving PEG were premedicated to reduce infusion reactions. Patients who developed HSR underwent PEG desensitization. Patients were compared to historic controls. Fifty-six patients were treated within the study period. There was no difference in the frequency of reactions before and after the adoption of universal premedication (p = 0.78). Eight patients (14.2%) developed either ≥ Grade 2 HSR or silent inactivation and 5 patients (62.5%) successfully underwent desensitization. The remaining three patients received EA asparaginase. This intervention led to a decrease in PEG substitution, with 3 patients (5.3%) requiring EA compared to 8 patients (15.09%) in the pre-intervention period. (p = 0.11) PEG desensitization was more cost effective than EA administration. PEG desensitization is a safe, cost effective, and practical alternative in children with ALL and a Grade 2 or higher HSR. [ABSTRACT FROM AUTHOR]

The early detection of anti‐asparaginase biomarker can facilitate timely modification of asparaginase chemotherapy, thereby avoiding serious complications. Herein we describe the preparation of a novel electrochemical biosensing interface for rapid detection of anti‐asparaginase in the picomolar range (1–10 000 pM). Coimmobilization of ferrocene and asparaginase on a carbon interface (via diazonium grafting) facilitates transduction through attenuation of the surface‐bound ferrocene redox couple. The limit of detection of 0.8 pM for this point‐of‐care applicable method compares favourably to that of traditional faradaic assaying (2.0 pM) where transduction occurs by the target blocking the diffusion of the solution redox probe [Fe(CN)6]3−/4−. [ABSTRACT FROM AUTHOR]

L-Asparaginase (ASNase) is a biopharmaceutical used as an essential drug in the treatment of acute lymphoblastic leukemia (ALL). Yet, some cases of ALL are naturally resistant to ASNase treatment, which results in poor prognosis. The REH ALL cell line, used as a model for studying the most common subtype of ALL, is considered resistant to treatment with ASNase. Cathepsin B (CTSB) is one of the proteases involved in the regulation of in vivo ASNase serum half-life and it has also been associated with the progression and resistance to treatment of several solid tumors. Previous works have shown that, in vitro, ASNase is degraded when incubated with REH cell lysate, which is prevented by a specific CTSB inhibitor, suggesting a function of this protease in the ASNase resistance of REH cells. In this work, we utilized a combination of CRISPR/Cas9 gene targeting and enzymatic measurements to investigate the relevance of CTSB on ASNase treatment resistance in the ALL model cell line. We found that deletion of CTSB in REH ALL cells did not confer ASNase treatment sensitivity, thus suggesting that intrinsic expression of CTSB is not a mechanism that drives the resistant nature of these ALL cells to enzymes used as the first-line treatment against leukemia. [ABSTRACT FROM AUTHOR]

Background: Asparaginase is a key component of chemotherapy protocols for the treatment of lymphoblastic malignancies among children. Adequate asparagine depletion is an important factor to achieve optimal therapeutic outcomes. Methods: Over a 3.5 year period, 106 patients were monitored for asparaginase activity (329 samples) in a single center of the Hungarian Pediatric Oncology–Hematology Group. In Hungary, three asparaginase products are available: native E. coli ASNase (Kidrolase), a pegylated form of this enzyme (Pegaspargase) and another native product from Erwinia chrysanthemi (Erwinase). A retrospective data analysis was performed. Results: In 81% (268/329) of our patients, AEA levels were in the optimal therapeutic range of over 100 IU/L. Of 106 patients, 13 (12%) were diagnosed with 'silent inactivation'. Conclusions: Monitoring of AEA can help to identify patients with 'silent inactivation' and their asparaginase therapy can thus be optimized. [ABSTRACT FROM AUTHOR]

Introduction: Hypertriglyceridemia (HTG) is one of the common complications of the regimens based on steroids and asparaginase used in the treatment of acute lymphoblastic leukemia (ALL) and lymphoblastic lymphoma (LBL) in children. The aim of this cross-sectional retrospective study was the analysis of the prevalence, clinical course and management of hypertriglyceridemia following the administration of asparaginase and steroids according to the binding protocols. Material and methods: A cohort of 75 children with ALL or LBL was analyzed with reference to anthropometric and laboratory parameters, clinical symptoms, implemented treatment, and complications. Results: The prevalence of HTG in the analyzed cohort was 29.3%. Risk factors for HTG development were older age, cachexia and lower body mass index, but there was no correlation with high risk group. Patients with HTG presented with elevated lipase acivity and total cholesterol concentration and decreased antithrombin, albumin, sodium and high-density lipoprotein cholesterol. Reported symptoms were unspecific. Management of HTG included: omega-3 fatty acids, fibrates, insulin and plasmapheresis. Conclusions: Hypertriglyceridemia is a significant complication of ALL and LBL treatment, and can lead to acute and late complications and cause unwelcome interruptions to therapy that can lead to poorer outcomes of treatment. As the course of HTG is oligosymptomatic, but can have undesirable repercussions, every patient receiving asparaginase with steroids should be monitored for HTG. It is also noteworthy that HTG can occur three or more weeks after asparaginase administration. [ABSTRACT FROM AUTHOR]

Summary: Asparaginase is an essential drug for acute lymphoblastic leukaemia (ALL) treatment, but has several side effects, and its discontinuation often compromises patient outcomes. In the prospective Japan Association of Childhood Leukaemia Study ALL‐02 protocol, two major changes were made: (1) additional chemotherapies to compensate for the reduction of treatment intensity when asparaginase was discontinued and (2) more intensive concomitant corticosteroid administration, relative to our previous ALL‐97 protocol. In ALL‐02 study, 1192 patients were included and L‐asparaginase was discontinued for 88 (7.4%). Discontinuation due to allergy was markedly decreased relative to the ALL‐97 protocol (2.3% vs 15.4%). Event‐free survival (EFS) among patients with T‐ALL was compromised when L‐asparaginase was discontinued, as well as among patients with high‐risk B‐cell ALL, especially when discontinued before maintenance therapy. Moreover, multivariate analysis identified discontinuation of L‐asparaginase as an independent poor prognostic factor for EFS. In the current study, additional chemotherapies failed to fully compensate for L‐asparaginase discontinuation, illustrating the difficulty of replacing asparaginase with other classes of drugs, although this study was not designed to evaluate the effect of these modifications. Concomitant intensive corticosteroid treatment may help to reduce allergy to asparaginase. These results will assist in further optimization of asparaginase use. [ABSTRACT FROM AUTHOR]

L-asparaginase (ASNase) is a protein that is essential for the treatment of acute lymphoblastic leukemia (ALL). The main types of ASNase that are clinically used involve native and pegylated Escherichia coli (E. coli)-derived ASNase as well as Erwinia chrysanthemi-derived ASNase. Additionally, a new recombinant E. coli-derived ASNase formulation has received EMA market approval in 2016. In recent years, pegylated ASNase has been preferentially used in high-income countries, which decreased the demand for non-pegylated ASNase. Nevertheless, due to the high cost of pegylated ASNase, non-pegylated ASNase is still widely used in ALL treatment in low- and middle-income countries. As a consequence, the production of ASNase products from low- and middle-income countries increased in order to satisfy the demand worldwide. However, concerns over the quality and efficacy of these products were raised due to less stringent regulatory requirements. In the present study, we compared a recombinant E. coli-derived ASNase marketed in Europe (Spectrila®) with an E. coli-derived ASNase preparation from India (Onconase) marketed in Eastern European countries. To assess the quality attributes of both ASNases, an in-depth characterization was conducted. Enzymatic activity testing revealed a nominal enzymatic activity of almost 100% for Spectrila®, whereas the enzymatic activity for Onconase was only 70%. Spectrila® also showed excellent purity as analyzed by reversed-phase high-pressure liquid chromatography, size exclusion chromatography and capillary zone electrophoresis. Furthermore, levels of process-related impurities were very low for Spectrila®. In comparison, the E. coli DNA content in the Onconase samples was almost 12-fold higher and the content of host cell protein was more than 300-fold higher in the Onconase samples. Our results reveal that Spectrila® met all of the testing parameters, stood out for its excellent quality and, thus, represents a safe treatment option in ALL. These findings are particularly important for low- and middle-income countries, where access to ASNase formulations is limited. [ABSTRACT FROM AUTHOR]

The enzyme Asparaginase, known as L-asparagine amidohydrolase, has anti-tumor properties and is widely used as a chemotherapeutic treatment for acute lymphoblastic leukemia. Many different organisms, including plants and terrestrial and microbes such as bacteria, fungi, algae and actinomycetes, have produced this enzyme. In this study, 34 isolates of the actinomycetes were collected from soil and water from different governorates in Egypt. Only nine Streptomyces isolates were identified by the presence of a pink hue around their colonial growth as an indication and had the best ability for the synthesis of extracellular Asparaginase. Glucose and peptone were effective carbon and nitrogen sources, respectively. The ideal pH for Asparaginase is 7, and the ideal temperature is 30 °C. and an incubation time of 7 days with a 0.4 % asparagine concentration. [ABSTRACT FROM AUTHOR]

Salmonella typhimurium is a pathogen responsible for causing a wide range of infectious diseases. The emergence of multi-drug resistance (MDR) in this microbe is a big challenge. L-asparaginase (less explored drug target) is selected as a drug target because it is actively involved in the virulence mechanism. To block this virulent enzyme, curcumin that is traditionally renowned for its medicinal properties was examined. However, its pharmacological behavior and targeting property is less understood because of its poor bioavailability. Therefore, the present work explores the antimicrobial effect of both curcumin and its degradation product against the MDR pathogen. Molecular docking studies were carried out to evaluate the inhibitory effect of curcumin and its degradation product against the L-asparaginase enzyme using Schrodinger Maestro interface tools. The Absorption, Distribution, Metabolism, Excretion and Toxicity (ADMET) profile of all the test ligands was also performed. The docking score of curcumin was −5.465 kcal/mol while its degradation product curcumin glucuronide has the lowest i.e., −6.240 kcal/mol. All the test ligands showed better or comparable docking scores with respect to control (Ciprofloxacin). Arg 142 and Asn 84 amino acid residues of L-asparaginase were found to be interacting with test ligands inside the binding pocket of the target protein. ADME/toxicology study also indicated the potency of curcumin/curcumin degradation products as a potent inhibitor. It was found that both curcumin and its degradation products have the potential to inhibit Salmonella. This information could be valuable for futuristic drug candidate development against this pathogen and could be a potential lead for mitigation of MDR. [ABSTRACT FROM AUTHOR]

PurposeThe Children's Oncology Group (COG) protocol AALL0434 evaluated the safety and efficacy of multi-agent chemotherapy with Capizzi-based methotrexate/pegaspargase (C-MTX) in patients with newly diagnosed pediatric T-cell lymphoblastic lymphoma (T-LL) and gained preliminary data using nelarabine in high-risk patients.Patients and methodsThe trial enrolled 299 patients, age 1-31 years. High-risk (HR) patients had ≥ 1% minimal detectable disease (MDD) in the bone marrow at diagnosis or received prior steroid treatment. Induction failure was defined as failure to achieve a partial response (PR) by the end of the 4-week induction. All patients received the augmented Berlin-Frankfurt-Muenster (ABFM) C-MTX regimen. HR patients were randomly assigned to receive or not receive 6 5-day courses of nelarabine incorporated into ABFM. Patients with induction failure were nonrandomly assigned to ABFM C-MTX plus nelarabine. No patients received prophylactic cranial radiation; however, patients with CNS3 disease (CSF WBC ≥ 5/μL with blasts or cranial nerve palsies, brain/eye involvement, or hypothalamic syndrome) were ineligible.ResultsAt end-induction, 98.8% of evaluable participants had at least a PR. The 4-year event-free survival (EFS) and overall survival (OS) were 84.7% ± 2.3% and 89.0% ± 2.0%. The 4-year disease-free survival (DFS) from end-induction was 85.9% ± 2.6%. There was no difference in DFS observed between the HR and standard-risk groups (P = .29) or by treatment regimen (P = .55). Disease stage, tumor response, and MDD at diagnosis did not demonstrate thresholds that resulted in differences in EFS. Nelarabine did not show an advantage for HR patients. CNS relapse occurred in only 4 patients.ConclusionCOG AALL0434 produced excellent outcomes in one of the largest trials ever conducted for patients with newly diagnosed T-LL. The COG ABFM regimen with C-MTX provided excellent EFS and OS without cranial radiation.

PurposeTreatment failure from drug resistance is the primary reason for relapse in acute lymphoblastic leukemia (ALL). Improving outcomes by targeting mechanisms of drug resistance is a potential solution.Patients and methodsWe report results investigating the epigenetic modulators decitabine and vorinostat with vincristine, dexamethasone, mitoxantrone, and PEG-asparaginase for pediatric patients with relapsed or refractory B-cell ALL (B-ALL). Twenty-three patients, median age 12 years (range, 1-21) were treated in this trial.ResultsThe most common grade 3-4 toxicities included hypokalemia (65%), anemia (78%), febrile neutropenia (57%), hypophosphatemia (43%), leukopenia (61%), hyperbilirubinemia (39%), thrombocytopenia (87%), neutropenia (91%), and hypocalcemia (39%). Three subjects experienced dose-limiting toxicities, which included cholestasis, steatosis, and hyperbilirubinemia (n = 1); seizure, somnolence, and delirium (n = 1); and pneumonitis, hypoxia, and hyperbilirubinemia (n = 1). Infectious complications were common with 17 of 23 (74%) subjects experiencing grade ≥3 infections including invasive fungal infections in 35% (8/23). Nine subjects (39%) achieved a complete response (CR + CR without platelet recovery + CR without neutrophil recovery) and five had stable disease (22%). Nine (39%) subjects were not evaluable for response, primarily due to treatment-related toxicities. Correlative pharmacodynamics demonstrated potent in vivo modulation of epigenetic marks, and modulation of biologic pathways associated with functional antileukemic effects.ConclusionsDespite encouraging response rates and pharmacodynamics, the combination of decitabine and vorinostat on this intensive chemotherapy backbone was determined not feasible in B-ALL due to the high incidence of significant infectious toxicities. This study is registered at http://www.clinicaltrials.gov as NCT01483690.

Asparaginase (ASNase) is an integral part of pediatric induction chemotherapy that has also been shown to improve adult survival rates; however, pegylated (PEG)-ASNase induces severe hepatotoxicity in this population. Recent case reports describe the incorporation of levocarnitine (LC) supplementation into PEG-ASNase-containing induction regimens to prevent or treat hepatotoxicity. Because LC facilitates the metabolism of free fatty acids (FFA), a primary fuel source for ALL cells, LC could potentially interfere with ALL chemotherapy efficacy. To test this, we employed in vitro and in vivo models of ALL. We show in vitro that LC supplementation does not impact cytotoxicity from vincristine, daunorubicin, dexamethasone, or ASNase on human ALL cells nor lead to an increase in ALL cell metabolic rate. In vivo, we demonstrate LC does not impair PEG-ASNase monotherapy in mice with syngeneic ALL. Together, our findings show that LC supplementation is a safe strategy to prevent/reverse ASNase-induced toxicities in preclinical models.

Background: L-asparaginase is an enzyme derived from E. coli and is one of the drugs used to treat acute lymphoblastic leukemia. Decreased blood asparagine after the use of the asparaginase can lead to death for these cells. The aim of this project is to investigate the possibility of the production and purification of theasparaginase enzyme. Methods: The asparaginase gene of E. coli was amplified using PCR technique. After purification, the gene was cloned into pET28a vector and transformed into a bacterial host. After transformation, different protein expression conditions were investigated for optimization. Recombinant enzyme expression was confirmed by SDS-PAGE and Western blotting. The asparaginase enzyme was then purified by affinity chromatography using a column containing Ni-NTA resin and a hybrid method and finally, its enzymatic activity was investigated. Findings: The high production of asparaginase enzyme in E. coli was at 37 °C, 1 mM concentration of IPTG, and incubation 20 hours after induction. Insoluble asparaginase enzyme was purified using a Ni-NTA column and the refolding process was performed on the column. According to the activity of the refolded enzyme in the enzyme activity test, it can be concluded that the refolding process of the enzyme has been done correctly. Conclusion: Due to the great importance of asparaginase production in Iran and the need of a group of patients to use this enzyme, in this project, by optimizing the expression and purification process, the L-asparaginase enzyme was produced on a laboratory scale.