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International Journal of Hematology Jun 2024Medications used to treat acute lymphoblastic leukemia (ALL), such as L-asparaginase, can cause blood lipid disturbances. These can also be associated with polymorphisms...
BACKGROUND
Medications used to treat acute lymphoblastic leukemia (ALL), such as L-asparaginase, can cause blood lipid disturbances. These can also be associated with polymorphisms of the lipoprotein lipase (LpL) and apolipoprotein E (APOE) genes.
PROCEDURE
We aimed to investigate the association between lipid profile, certain LpL and APOE gene polymorphisms (rs268, rs328, rs1801177 and rs7412, rs429358 respectively) as well as the risk subgroup in 30 pediatric patients being treated for ALL, compared with 30 pediatric ALL survivors and 30 healthy controls.
RESULTS
The only APOE gene polymorphism with significant allelic and genotypic heterogeneity was rs429358. Further analysis of this polymorphism showed that genotype (CC, CT, or TT) was significantly associated with (1) changes in the lipid profile at the end of consolidation (total cholesterol, LDL, apo-B100, and lipoprotein a) and during re-induction (total cholesterol and apo-B100), and (2) classification in the high risk-ALL subgroup (for CC genotype/C allele presence).
CONCLUSIONS
Lipid abnormalities in children being treated for ALL may be associated with the APOE genotype, which is also possibly associated with risk stratification. Further research is needed to confirm the potential prognostic value of these findings.
Topics: Humans; Apolipoproteins E; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Child; Male; Female; Lipoprotein Lipase; Child, Preschool; Lipids; Adolescent; Polymorphism, Single Nucleotide; Genotype; Alleles; Asparaginase; Polymorphism, Genetic
PubMed: 38507115
DOI: 10.1007/s12185-024-03748-6 -
Protein Science : a Publication of the... Apr 2024L-Asparaginases (ASNases) catalyze the hydrolysis of L-Asn to L-Asp and ammonia. Members of the ASNase family are used as drugs in the treatment of leukemia, as well as...
L-Asparaginases (ASNases) catalyze the hydrolysis of L-Asn to L-Asp and ammonia. Members of the ASNase family are used as drugs in the treatment of leukemia, as well as in the food industry. The protomers of bacterial ASNases typically contain 300-400 amino acids (typical class 1 ASNases). In contrast, the chain of ASNase from Rhodospirillum rubrum, reported here and referred to as RrA, consists of only 172 amino acid residues. RrA is homologous to the N-terminal domain of typical bacterial class 1 ASNases and exhibits millimolar affinity for L-Asn. In this study, we demonstrate that RrA belongs to a unique family of cytoplasmic, short-chain ASNases (scASNases). These proteins occupy a distinct region in the sequence space, separate from the regions typically assigned to class 1 ASNases. The scASNases are present in approximately 7% of eubacterial species, spanning diverse bacterial lineages. They seem to be significantly enriched in species that encode for more than one class 1 ASNase. Here, we report biochemical, biophysical, and structural properties of RrA, a member of scASNases family. Crystal structures of the wild-type RrA, both with and without bound L-Asp, as well as structures of several RrA mutants, reveal topologically unique tetramers. Moreover, the active site of one protomer is complemented by two residues (Tyr21 and Asn26) from another protomer. Upon closer inspection, these findings clearly outline scASNases as a stand-alone subfamily of ASNases that can catalyze the hydrolysis of L-Asn to L-Asp despite the lack of the C-terminal domain that is present in all ASNases described structurally to date.
Topics: Asparaginase; Rhodospirillum rubrum; Protein Subunits; Aspartic Acid; Catalytic Domain
PubMed: 38501449
DOI: 10.1002/pro.4920 -
British Journal of Haematology Jun 2024Physiologically based pharmacokinetic (PBPK) modelling is an alternative modelling technique that is increasingly used in pharmacokinetics. Due to its nature, it can be... (Randomized Controlled Trial)
Randomized Controlled Trial
Physiologically based pharmacokinetic (PBPK) modelling is an alternative modelling technique that is increasingly used in pharmacokinetics. Due to its nature, it can be complementarily employed to population pharmacokinetics, especially when it comes to small population size. Here, we report the proof of concept of its application to accurately describe the pharmacokinetics of a recombinant L-asparaginase in paediatric patients with acute lymphoblastic leukaemia. Data from two randomized, double-blind, phase II/III clinical studies (MC-ASP.4/ALL; MC-ASP.5/ALL) were included to setup and evaluate the final model, respectively. Final population values for basic pharmacokinetic parameters were calculated (clearance: 0.0569 L/h/19.5 kg, volume of distribution: 1.251 L, half-life: 18.5 h, trough concentration: 140.9 IU/L). Pharmacokinetic parameter prediction as well as predictive performance of the model proofed to be comparable to a separately developed population pharmacokinetic model with 13% deviation in predicted median L-asparaginase trough levels. To the best of our knowledge, this is the first whole-body PBPK model of a non-antibody therapeutic protein.
Topics: Humans; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Asparaginase; Child; Models, Biological; Child, Preschool; Female; Male; Adolescent; Proof of Concept Study; Double-Blind Method; Antineoplastic Agents; Infant
PubMed: 38494194
DOI: 10.1111/bjh.19410 -
Journal of Applied Microbiology Mar 2024To identify a marine L-asparaginase with clinically desirable attributes and characterize the shortlisted candidate through in silico tools.
AIMS
To identify a marine L-asparaginase with clinically desirable attributes and characterize the shortlisted candidate through in silico tools.
METHODS AND RESULTS
Marine bacterial strains (number = 105) isolated from marine crabs were evaluated through a stepwise strategy incorporating the crucial attributes for therapeutic safety. The results demonstrated the potential of eight bacterial species for extracellular L-asparaginase production. However, only one isolate (Bacillus altitudinis CMFRI/Bal-2) showed clinically desirable attributes, viz. extracellular production, type-II nature, lack of concurrent L-glutaminase and urease activities, and presence of ansZ (functional gene for clinical type). The enzyme production was 22.55 ± 0.5 µM/mg protein/min within 24 h without optimization. The enzyme also showed good activity and stability in pH 7-8 and temperature 37°C, predicting the functioning inside the human body. The Michealis-Menten constant (Km) was 14.75 µM. Detailed in silico analysis based on functional gene authenticating the results of in vitro characterization and predicted the nonallergenic characteristic of the candidate. Docking results proved the higher affinity of the shortlisted candidate to L-asparagine than L-glutamine and urea.
CONCLUSION
Comprehensively, the study highlighted B. altitudinis type II asparaginase as a competent candidate for further research on clinically safe asparaginases.
Topics: Humans; Asparaginase; Bacillus; Asparagine; Temperature
PubMed: 38467390
DOI: 10.1093/jambio/lxae062 -
Frontiers in Chemistry 2024L-Asparaginases, divided into three structural Classes, catalyze the hydrolysis of L-asparagine to L-aspartic acid and ammonia. The members of Class 3, ReAIV and ReAV,...
L-Asparaginases, divided into three structural Classes, catalyze the hydrolysis of L-asparagine to L-aspartic acid and ammonia. The members of Class 3, ReAIV and ReAV, encoded in the genome of the nitrogen fixing , have the same fold, active site, and quaternary structure, despite low sequence identity. In the present work we examined the biochemical consequences of this difference. ReAIV is almost twice as efficient as ReAV in asparagine hydrolysis at 37°C, with the kinetic K, k parameters (measured in optimal buffering agent) of 1.5 mM, 770 s and 2.1 mM, 603 s, respectively. The activity of ReAIV has a temperature optimum at 45°C-55°C, whereas the activity of ReAV, after reaching its optimum at 37°C, decreases dramatically at 45°C. The activity of both isoforms is boosted by 32 or 56%, by low and optimal concentration of zinc, which is bound three times more strongly by ReAIV then by ReAV, as reflected by the K values of 1.2 and 3.3 μM, respectively. We also demonstrate that perturbation of zinc binding by Lys→Ala point mutagenesis drastically decreases the enzyme activity but also changes the mode of response to zinc. We also examined the impact of different divalent cations on the activity, kinetics, and stability of both isoforms. It appeared that Ni, Cu, Hg, and Cd have the potential to inhibit both isoforms in the following order (from the strongest to weakest inhibitors) Hg > Cu > Cd > Ni. ReAIV is more sensitive to Cu and Cd, while ReAV is more sensitive to Hg and Ni, as revealed by IC50 values, melting scans, and influence on substrate specificity. Low concentration of Cd improves substrate specificity of both isoforms, suggesting its role in substrate recognition. The same observation was made for Hg in the case of ReAIV. The activity of the ReAV isoform is less sensitive to Cl anions, as reflected by the IC50 value for NaCl, which is eightfold higher for ReAV relative to ReAIV. The uncovered complementary properties of the two isoforms help us better understand the inducibility of the ReAV enzyme.
PubMed: 38456185
DOI: 10.3389/fchem.2024.1373312 -
Scientific Reports Mar 2024A dataset comprising metagenomes of outpatients (n = 28) with acute leukemia (AL) and healthy controls (n = 14) was analysed to investigate the associations...
A dataset comprising metagenomes of outpatients (n = 28) with acute leukemia (AL) and healthy controls (n = 14) was analysed to investigate the associations between gut microbiota composition and metabolic activity and AL. According to the results obtained, no significant differences in the microbial diversity between AL outpatients and healthy controls were found. However, significant differences in the abundance of specific microbial clades of healthy controls and AL outpatients were found. We found some differences at taxa level. The relative abundance of Enterobacteriaceae, Prevotellaceae and Rikenellaceae was increased in AL outpatients, while Bacteirodaceae, Bifidobacteriaceae and Lachnospiraceae was decreased. Interestingly, the abundances of several taxa including Bacteroides and Faecalibacterium species showed variations based on recovery time from the last cycle of chemotherapy. Functional annotation of metagenome-assembled genomes (MAGs) revealed the presence of functional domains corresponding to therapeutic enzymes including L-asparaginase in a wide range of genera including Prevotella, Ruminococcus, Faecalibacterium, Alistipes, Akkermansia. Metabolic network modelling revealed potential symbiotic relationships between Veillonella parvula and Levyella massiliensis and several species found in the microbiota of AL outpatients. These results may contribute to develop strategies for the recovery of microbiota composition profiles in the treatment of patients with AL.
Topics: Humans; Gastrointestinal Microbiome; Feces; Bacteria; Microbiota; Leukemia, Myeloid, Acute; Bacteroidetes
PubMed: 38454103
DOI: 10.1038/s41598-024-56054-w -
Cell Communication and Signaling : CCS Mar 2024Asparagine, an important amino acid in mammals, is produced in several organs and is widely used for the production of other nutrients such as glucose, proteins, lipids,... (Review)
Review
Asparagine, an important amino acid in mammals, is produced in several organs and is widely used for the production of other nutrients such as glucose, proteins, lipids, and nucleotides. Asparagine has also been reported to play a vital role in the development of cancer cells. Although several types of cancer cells can synthesise asparagine alone, their synthesis levels are insufficient to meet their requirements. These cells must rely on the supply of exogenous asparagine, which is why asparagine is considered a semi-essential amino acid. Therefore, nutritional inhibition by targeting asparagine is often considered as an anti-cancer strategy and has shown success in the treatment of leukaemia. However, asparagine limitation alone does not achieve an ideal therapeutic effect because of stress responses that upregulate asparagine synthase (ASNS) to meet the requirements for asparagine in cancer cells. Various cancer cells initiate different reprogramming processes in response to the deficiency of asparagine. Therefore, it is necessary to comprehensively understand the asparagine metabolism in cancers. This review primarily discusses the physiological role of asparagine and the current progress in the field of cancer research.
Topics: Animals; Asparagine; Neoplasms; Leukemia; Amino Acids; Glucose; Mammals
PubMed: 38448969
DOI: 10.1186/s12964-024-01540-x -
Signal Transduction and Targeted Therapy Mar 2024Natural killer T cell lymphoma (NKTCL) is highly aggressive, with advanced stage patients poorly responding to intensive chemotherapy. To explore effective and safe...
Natural killer T cell lymphoma (NKTCL) is highly aggressive, with advanced stage patients poorly responding to intensive chemotherapy. To explore effective and safe treatment for newly diagnosed advanced stage NKTCL, we conducted a phase II study of anti-metabolic agent pegaspargase plus PD-1 antibody sintilimab (NCT04096690). Twenty-two patients with a median age of 51 years (range, 24-74) were enrolled and treated with induction treatment of pegaspargase 2500 IU/m intramuscularly on day 1 and sintilimab 200 mg intravenously on day 2 for 6 cycles of 21 days, followed by maintenance treatment of sintilimab 200 mg for 28 cycles of 21 days. The complete response and overall response rate after induction treatment were 59% (95%CI, 43-79%) and 68% (95%CI, 47-84%), respectively. With a median follow-up of 30 months, the 2 year progression-free and overall survival rates were 68% (95%CI, 45-83%) and 86% (95%CI, 63-95%), respectively. The most frequently grade 3/4 adverse events were neutropenia (32%, n = 7) and hypofibrinogenemia (18%, n = 4), which were manageable and led to no discontinuation of treatment. Tumor proportion score of PD-L1, peripheral blood high-density lipoprotein cholesterol, and apolipoprotein A-I correlated with good response, while PD-1 on tumor infiltrating lymphocytes and peripheral Treg cells with poor response to pegaspargase plus sintilimab treatment. In conclusion, the chemo-free regimen pegaspargase plus sintilimab was effective and safe in newly diagnosed, advanced stage NKTCL. Dysregulated lipid profile and immunosuppressive signature contributed to treatment resistance, providing an alternative therapeutic approach dual targeting fatty acid metabolism and CTLA-4 in NKTCL.
Topics: Humans; Antibodies, Monoclonal, Humanized; Asparaginase; Lymphoma; Natural Killer T-Cells; Polyethylene Glycols; Programmed Cell Death 1 Receptor; Adult; Middle Aged; Aged; Young Adult
PubMed: 38448403
DOI: 10.1038/s41392-024-01782-8 -
ChemPlusChem Mar 2024Enzyme immobilization can offer a range of significant advantages, including reusability, and increased selectivity, stability, and activity. In this work, a central...
Enzyme immobilization can offer a range of significant advantages, including reusability, and increased selectivity, stability, and activity. In this work, a central composite design (CCD) of experiments and response surface methodology (RSM) were used to study, for the first time, the L-asparaginase (ASNase) immobilization onto functionalized carbon xerogels (CXs). The best results were achieved using CXs obtained by hydrothermal oxidation with nitric acid and subsequent heat treatment in a nitrogen flow at 600 °C (CX-OX-600). Under the optimal conditions (81 min of contact time, pH 6.2 and 0.36 g/L of ASNase), an immobilization yield (IY) of 100 % and relative recovered activity (RRA) of 103 % were achieved. The kinetic parameters obtained also indicate a 1.25-fold increase in the affinity of ASNase towards the substrate after immobilization. Moreover, the immobilized enzyme retained 97 % of its initial activity after 6 consecutive reaction cycles. All these outcomes confirm the promising properties of functionalized CXs as support for ASNase, bringing new insights into the development of an efficient and stable immobilization platform for use in the pharmaceutical industry, food industry, and biosensors.
PubMed: 38436967
DOI: 10.1002/cplu.202400025