A systematic review and meta-analysis of the effectiveness of primary thromboprophylaxis in acute lymphoblastic leukemia during early-phase therapy including asparaginase or its prolonged form

Asparaginase is essential in the initial management of acute lymphoblastic leukemia (ALL) but frequently leads to venous thromboembolism (VTE). Using anticoagulants for primary VTE prevention has been studied with no consensus. We conducted a systematic literature search in PubMed, Scopus, and Web of science and performed random-effect meta-analysis using Mantel-Haenszel method in RevMan 5.4 to analyze primary pharmacological thromboprophylaxis during asparaginase treatment in early-phase (induction, consolidation, or intensification phase) therapy in patients with ALL with all ages and followed with subgroup analysis by age. Meta-analysis of 13 articles describing the effect of antithrombin supplementation in 1375 patients showed that antithrombin prophylaxis decreases the risk of VTE by 43% (RR, 0.57; 95% CI, 0.38 - 0.83; p=0.004), with mild heterogeneity (I2=35%, p=0.10) and moderate certainty by GRADE. 8 articles included for meta-analysis of low-molecular weight heparin (LMWH) treatment in 612 patients showed that it decreased the risk of VTE by nearly 40% (RR, 0.61; 95% CI, 0.45 - 0.81; p=0.00081), with minimal heterogeneity (I2=14%, p=0.31) but low certainty. Subgroup analysis showed that only prophylaxis with antithrombin supplementation significantly decreased the VTE rate in adult patients with moderate certainty. In pediatric patients, one nonrandomized prospective study showed that LMWH combined with antithrombin has a better thromboprophylaxis effect than antithrombin alone. In the PREVAPIX-ALL trial, prophylaxis with direct factor Xa inhibitor Apixaban did not benefit children younger than 18 years except for cases of obesity. We concluded that thromboprophylaxis with antithrombin is effective in ALL patients older than 18 years during the early phase of therapy, and LMWH combined with antithrombin supplementation might be effective for pediatric patients with ALL. Apixaban is effective in pediatric ALL patients with obesity and needs further study in other high-risk patients.

First-line sintilimab with pegaspargase, gemcitabine, and oxaliplatin in advanced extranodal natural killer/T cell lymphoma (SPIRIT): a multicentre, single-arm, phase 2 trial

BACKGROUND

Programmed cell death protein 1 (PD-1) inhibitor sintilimab is effective in relapsed and refractory extranodal natural killer/T cell lymphoma (ENKTL), nasal type. We aimed to assess the safety and activity of sintilimab plus P-GEMOX (pegaspargase, gemcitabine, and oxaliplatin) in the first-line setting for advanced ENKTL.

METHODS

The multicentre, single-arm, phase 2 trial was done at three medical centres in China. Patients aged 18-75 years with treatment-naive pathologically confirmed advanced ENKTL and an with Eastern Cooperative Oncology Group performance status score of 0-2 were eligible. Patients received intravenous sintilimab (200 mg on day 1), intramuscular pegaspargase (2000 U/m2 on day 1), intravenous gemcitabine (1 g/m2 on days 1 and 8), and intravenous oxaliplatin (130 mg/m2 on day 1) every 3 weeks for six cycles, followed by intravenous sintilimab (200 mg) every 3 weeks for up to 2 years or until disease progression or unacceptable toxicities. The primary endpoint was the complete response rate in the intention-to-treat population. The secondary endpoints were overall response rate (ORR), progression-free survival (PFS), disease-free survival (DFS), and overall survival. This trial is registered with ClinicalTrials.gov, NCT04127227. Enrolment has been completed, and follow-up is ongoing.

FINDINGS

Between Nov 29, 2019, and Sept 7, 2022, 34 eligible patients were enrolled (median age 39 years [IQR 32-55]; 25 [74%] of 34 patients were male; nine [26%] were female; and all were of Asian ethnicity). At the data cutoff (July 20, 2023), the median follow-up was 21 months (IQR 13-32). The complete response rate was 85% (29 of 34 patients, 95% CI 70-94). Five patients (15%; 95% CI 7-30) attained partial response and the ORR was 100% (34 of 34 patients). 24-month PFS was 64% (95% CI 48-86), 24-month DFS was 72% (54-95), and 36-month overall survival was 76% (52-100). The most common grade 3 or 4 treatment-related adverse events were neutropenia (17 [50%] of 34 patients), anaemia (10 [29%] patients), and hypertriglyceridemia (10 [29%] patients). Hypothyroidism was the most frequent immune-related adverse event (18 [53%]), including grade 3 hypothyroidism in one (3%) patient that caused treatment termination. No severe adverse events occurred. There were three deaths: one due to haemophagocytic syndrome, one due to disease progression, and one due to unknown cause, which were not considered to be treatment related.

INTERPRETATION

Combination of sintilimab with P-GEMOX seems to be an active and safe first-line regimen for patients with advanced ENKTL.

FUNDING

National Key Research and Development Program and National Natural Science Foundation of China, Guangzhou Science and Technology Program and the Clinical Oncology Foundation of Chinese Society of Clinical Oncology.

Extranodal nasal-type NK/T lymphoma treated with chemotherapy and radiotherapy: case series from a European tertiary referral center and review of the literature

PURPOSE

Extranodal nasal-type NK/T-cell lymphoma (ENKTL) is very rare in western countries and few data are available regarding the prognosis and the outcome of patients treated for this disease. We aimed to evaluate the prognosis, the pattern and risk factors of disease failure after combined therapy and also performed a review of the literature.

PATIENTS AND METHODS

We retrospectively analyzed 20 patients with (ENKTL) who underwent L‑Asparaginase based chemotherapy followed by (chemo-) radiotherapy between 2010 and 2020 in our center. Data on clinical characteristics and irradiation were collected. Failure patterns were recorded as local (tumor site), regional (regional lymph nodes) or distant failure (metastasis and/or nonregional lymph nodes).

RESULTS

During a median follow-up period of 46 months, disease failure was observed in 8 patients (40%). The 3‑year progression-free survival (PFS) and overall survival (OS) rates were 62.5 and 83.0%, respectively. The failure patterns were local (n = 6, 30%), regional (n = 3, 15%) and distant (n = 4, 20%). Among patients with local failure, all failures occurred within the radiation fields (100%). Univariate analysis showed that bilateral regional lymph node involvement (p = 0.0002), initial circulating EBV viral load ≥ 3.5 log (p = 0.03) and no negativation of EBV PCR after induction CT (p = 0.0497) were independent predictors of PFS.

CONCLUSION

Patients with bilateral lymph node involvement and/or high EBV viral load have a significant recurrence rate despite multimodal therapy. These results need to be confirmed by larger studies. Given the high rate of local recurrence within radiotherapy fields, the value of dose escalation should be considered. Patients at risk of relapse should be included in dedicated trials.

Pharmacokinetics of PEGasparaginase in Infants with Acute Lymphoblastic Leukemia

BACKGROUND

PEGasparaginase is known to be a critical drug for treating pediatric acute lymphoblastic leukemia (ALL), however, there is insufficient evidence to determine the optimal dose for infants who are less than one year of age at diagnosis. This international study was conducted to identify the pharmacokinetics of PEGasparaginase in infants with newly diagnosed ALL and gather insight into the clearance and dosing of this population.

METHODS

Infants with ALL who received treatment with PEGasparaginase were included in our population pharmacokinetic assessment employing non-linear mixed effects modelling (NONMEM).

RESULTS

68 infants with ALL, with a total of 388 asparaginase activity samples, were included. PEGasparaginase doses ranging from 400 to 3,663 IU/m2 were administered either intravenously or intramuscularly. A one-compartment model with time-dependent clearance, modeled using a transit model, provided the best fit to the data. Body weight was significantly correlated with clearance and volume of distribution. The final model estimated a half-life of 11.7 days just after administration, which decreased to 1.8 days 14 days after administration. Clearance was 19.5% lower during the post-induction treatment phase compared to induction.

CONCLUSION

The pharmacokinetics of PEGasparaginase in infants diagnosed under one year of age with ALL is comparable to that of older children (1-18 years). We recommend a PEGasparaginase dosing at 1,500 IU/m2 for infants without dose adaptations according to age, and implementing therapeutic drug monitoring as standard practice.

In vitro chemosensitivity testing of the feline large granular lymphocyte cell line (S87)

BACKGROUND

Feline large granular lymphocyte (LGL) lymphoma is an aggressive neoplasia characterised by short survival and poor response to chemotherapy.

OBJECTIVES

In this study, the effect of different chemotherapeutic agents on the growth kinetics of the feline cell line S87, a non-MHC-restricted feline LGL cell line, was investigated. Where possible, IC50 (inhibitory concentration 50) values were determined. The IC50 values of the cell line as lymphoma models can provide clues to the situation in vivo and serve as a basis for studying resistance mechanisms.

METHODS

Cells were incubated with various concentrations of vincristine, doxorubicin, 4-hydroperoxycyclophosphamide, prednisolone, methotrexate and L-asparaginase for 24 and 48 h, respectively.

RESULTS

The IC50 values could be determined as 14.57 (7.49-28.32) μg/mL at 24 h incubation and 5.72 (4.05-8.07) μg/mL at 48 h incubation for doxorubicin and 9.12 (7.72-10.76) μg/mL at 24 h incubation and 4.53 (3.74-5.47) μg/mL at 48 h incubation for 4-hydroperpoxycyclophosphamide. Treatment with vincristine and methotrexate resulted in relatively high cell resistance whereas L-asparaginase and prednisolone treatment led to a reduction in cell number compared to control while cell viability was not affected (cytostatic effect).

CONCLUSION

Overall, the feline LGL cell line S87 proves to be relatively sensitive to doxorubicin and 4-hydroperoxycyclophosphamide and relatively resistant to treatment with vincristine, prednisolone, methotrexate and L-asparaginase. The results of this study can be used for further investigations on resistance mechanisms in feline LGL lymphoma. Doxorubicin and cyclophosphamide can be interpreted as promising candidates for the therapy of feline LGL lymphomas.

Treatment completion, asparaginase completion, and oncologic outcomes among children, adolescents and young adults with acute lymphoblastic leukemia treated with DFCI Consortium Protocols

Adolescents and young adult (AYA) patients with acute lymphoblastic leukemia (ALL) face worse outcomes than children. While pediatric-inspired protocols have improved outcomes, the ability of patients to complete these intensive regimens and the reasons for discontinuation are unknown. We analyzed a cohort of 332 AYA patients (aged 15-49 years) and 1159 children (aged 1-14 years) with Ph-negative ALL treated on DFCI consortium protocols. We found that AYA patients completed treatment at lower rates than children (60.8% vs. 89.7%, p < 0.001), primarily due to higher rates of early treatment failure (14.5% vs. 2.4%, p < 0.001). Withdrawal from treatment for toxicity, social/personal, or unknown reasons was uncommon, but higher among AYA patients (9.3% vs 4.7%, p = 0.001). Patients who remained on assigned therapy for one year had favorable overall survival (AYA 5-year OS 88.9%; children 5-year OS 96.4%; p < 0.001). Among patients who continued treatment for 1 year, AYA patients completed asparaginase (defined as receiving 26+ weeks) at lower rates than children (79.1% vs. 89.6%, p < 0.001). Patients who received more weeks of consolidation asparaginase had higher overall and event-free survival. Efforts should focus on identifying patients at risk for early treatment failure and optimizing asparaginase delivery.

Selinexor With Anti-PD-1 Antibody as a Potentially Effective Regimen for Patients With Natural Killer/T-Cell Lymphoma Failing Prior L-Asparaginase and PD-1 Blockade

BACKGROUND

Natural killer/T-cell lymphoma (NKTCL) is a rare and heterogeneous tumor type of non-Hodgkin's lymphoma (NHL) with a poor clinical outcome. There is no standardized salvage treatment failing l-asparaginase-based regimens. Here we report our retrospective results of the combined use of selinexor and PD-1 blockade (tislelizumab) in 5 patients with NKTCL who had exhausted almost all available treatments.

PATIENTS AND METHODS

A total of 5 patients with relapsed/refractory(R/R) NK/T-cell lymphomas failing prior l-asparaginase and anti-PD-1 antibody were retrospectively collected. They were treated with at least one cycle of XPO1 inhibitor plus the same anti-PD-1 antibody. Anti-PD-1 antibody (Tislelizumab) was administrated at 200 mg on day 1 every 3 weeks and selinexor doses and schedules ranged from 40 mg weekly for 2 weeks per 21-day cycle to 60 mg weekly per cycle.

RESULTS

Five patients with relapsed NKTCL with extensive organ involvement including 4 central nervous system (CNS) infiltration patients were included. Four patients achieved objective responses including 3 complete responses (CR) and 1 partial response (PR). After a median follow-up time of 14.5 (range, 5-22) months, 1 patient was still in remission with CR, and the other 4 patients discontinued due to disease progression with a median progression-free survival (PFS) of 6 months and median overall survival (OS) of 12 months. Four patients with CNS involvement achieved a median OS of 8 months. Our data suggest that selinexor in combination with an anti-PD-1 antibody is a promising small molecule and immunotherapy combination regimen for patients with relapsed or refractory NKTCL.

Towards development of biobetter: L-asparaginase a case study

BACKGROUND

L-asparaginase (ASNase) has played a key role in the management of acute lymphoblastic leukaemia (ALL). As an amidohydrolase, it catalyzes the hydrolysis of L-asparagine, a crucial step in the treatment of ALL. Various ASNase variants have evolved from diverse sources since it was first used in paediatric patients in the 1960s. This review describes the available ASNase and approaches being used to develop ASNase as a biobetter candidate.

SCOPE OF REVIEW

The review discusses the Glycosylation and PEGylation techniques, which are frequently used to develop biobetter versions of the majority of the therapeutic proteins. Further, it explores current ASNase biobetters in therapeutic use and discusses the protein engineering and chemical modification approaches that were employed to reduce immunogenicity, extend protein half-life, and enhance protease stability of ASNase. Emerging strategies like immobilization and encapsulation are also highlighted as potential pathways for improving ASNase properties.

MAJOR CONCLUSIONS

The purpose of the development of ASNase biobetter is to achieve a novel therapeutic candidate that could improve catalytic efficiency, in vivo stability with minimum glutaminase (GLNase) activity and toxicity. Modification of ASNase by immobilization and encapsulation or by fusion technologies like Albumin fusion, Fc fusion, ELP fusion, XTEN fusion, etc. can be exploited to develop a novel biobetter candidate suitable for therapeutic approaches.

GENERAL SIGNIFICANCE

This review emphasizes the importance of biobetter development for therapeutic proteins like ASNase. Improved ASNase molecules have the potential to significantly advance the treatment of ALL and have broader implications in the pharmaceutical industry.

Lack of benefit from premedication for pegylated asparaginase during pediatric acute lymphoblastic leukemia/lymphoma therapy: A side-by-side comparison

BACKGROUND

Pegylated l-asparaginase (PEG) is integral to treatment regimens for acute lymphoblastic leukemia (ALL) and lymphoma. Hypersensitivity reactions (HSRs) to PEG are common and can preclude continued administration. Data supporting recommendations for universal premedication (UPM) prior to PEG infusion to reduce incidence of HSRs are limited; UPM has become common practice.

PROCEDURES

Two free-standing children's hospitals independently implemented UPM prior to PEG infusions in 2016 and 2019, respectively. In a side-by-side retrospective analysis, incidence and severity of HSRs were analyzed pre- and postimplementation of UPM in youth ≥1 years old treated with frontline PEG-containing ALL regimens (2015-2018, 2016-2020). All HSRs were centrally reviewed within each institution to confirm and grade the HSR (Common Terminology Criteria for Adverse Events, v5). Planned analyses of subsets at potentially greater risk for HSRs included intensive PEG regimens (≥5 doses), adolescent and young adults (AYA), Hispanic/Latinx ethnicity, and obesity.

RESULTS

In 410 patients (by institution, n = 282 and n = 128), the overall incidence of Grade ≥ 3 HSRs was 20% (56 out of 282) and 18% (23 out of 128), respectively. No difference in incidence of Grade ≥ 3 HSRs in patients with versus without UPM was found at either institution (23 vs. 19%, p = .487 and 19 vs. 17%, p = .845). UPM also did not reduce the severity of HSRs, nor influence HSR risk within any patient subset.

CONCLUSIONS

UPM prior to PEG infusion did not alter incidence or severity of HSRs at either institution. HSR remains a common complication of PEG therapy, impacting the patient experience. Alternative strategies to reduce HSRs are urgently required.

Dissecting dual specificity: Identifying key residues in L-asparaginase for enhanced acute lymphoid leukemia therapy and reduced adverse effects

L-asparaginase from Escherichia coli (EcA) has been used for the treatment of acute lymphoid leukemia (ALL) since the 1970s. Nevertheless, the enzyme has a second specificity that results in glutaminase breakdown, resulting in depletion from the patient's body, causing severe adverse effects. Despite the huge interest in the use of this enzyme, the exact process of glutamine depletion is still unknown and there is no consensus regarding L-asparagine hydrolysis. Here, we investigate the role of T12, Y25, and T89 in asparaginase and glutaminase activities. We obtained individual clones containing mutations in the T12, Y25 or T89 residues. After the recombinant production of wild-type and mutated EcA, The purified samples were subjected to structural analysis using Nano Differential Scanning Fluorimetry, which revealed that all samples contained thermostable molecules in their active structural conformation, the homotetramer conformation. The quaternary conformation was confirmed by DLS and SEC. The activity enzymatic assay combined with molecular dynamics simulation identified the contribution of T12, Y25, and T89 residues in EcA glutaminase and asparaginase activities. Our results mapped the enzymatic behavior paving the way for the designing of improved EcA enzymes, which is important in the treatment of ALL.

Development of a bioengineered Erwinia chrysanthemi asparaginase to enhance its anti-solid tumor potential for treating gastric cancer

Asparaginase has been traditionally applied for only treating acute lymphoblastic leukemia due to its ability to deplete asparagine. However, its ultimate anticancer potential for treating solid tumors has not yet been unleashed. In this study, we bioengineered Erwinia chrysanthemi asparaginase (ErWT), one of the US Food and Drug Administration-approved types of amino acid depleting enzymes, to achieve double amino acid depletions for treating a solid tumor. We constructed a fusion protein by joining an albumin binding domain (ABD) to ErWT via a linker (GGGGS)5 to achieve ABD-ErS5. The ABD could bind to serum albumin to form an albumin-ABD-ErS5 complex, which could avoid renal clearance and escape from anti-drug antibodies, resulting in a remarkably prolonged elimination half-life of ABD-ErS5. Meanwhile, ABD-ErS5 did not only deplete asparagine but also glutamine for ∼2 weeks. A biweekly administration of ABD-ErS5 (1.5 mg/kg) significantly suppressed tumor growth in an MKN-45 gastric cancer xenograft model, demonstrating a novel approach for treating solid tumor depleting asparagine and glutamine. Multiple administrations of ABD-ErS5 did not cause any noticeable histopathological abnormalities of key organs, suggesting the absence of acute toxicity to mice. Our results suggest ABD-ErS5 is a potential therapeutic candidate for treating gastric cancer.

Polyoxazoline-Conjugated l-Asparaginase: An Antibody-Production-Free Therapeutic Agent for Acute Lymphoblastic Leukemia

l-asparaginase (ASNase), an enzyme that catalyzes the hydrolysis of l-asparagine into l-aspartic acid, is frequently used as a medication for acute lymphoblastic leukemia (ALL). However, when derived from bacterial sources, this enzyme can elicit side effects, including allergic or hypersensitivity reactions, owing to immune responses. Here, we describe the synthesis of polyoxazoline-conjugated ASNase (POx-ASNase) and investigate its enzyme activity, anticancer efficacy, immunogenicity, and retention in the bloodstream. The water-soluble POx was coupled with surface lysine residues of ASNase using a bifunctional cross-linker. The average number of polymers bound to each enzyme was determined as 10. Although the enzymatic activity of POx-ASNase decreased to 56% of that of native ASNase, its temperature and pH dependencies remained unaltered. Remarkably, the lyophilized powder form of POx-ASNase retained its catalytic ability for 24 months. POx-ASNase demonstrated nearly identical anticancer efficacy compared to naked ASNase against leukemia and lymphoma cells (MOLT-4, CLBL-1, and K562) while displaying no cytotoxicity toward normal cells. Animal experiments conducted using rats revealed that the POx decoration suppressed the generation of anti-ASNase IgM and IgG antibodies with no detection of anti-POx antibodies. The half-life within the bloodstream extended to 34 h, representing a 17-fold increase compared to unmodified ASNase. These findings suggest that POx-ASNase serves as an anticancer therapeutic agent, characterized by the absence of antibody production and notably extended circulation persistence.

Prognostic and Pharmacotypic Heterogeneity of Hyperdiploidy in Childhood ALL

PURPOSE

High hyperdiploidy, the largest and favorable subtype of childhood ALL, exhibits significant biological and prognostic heterogeneity. However, factors contributing to the varied treatment response and the optimal definition of hyperdiploidy remain uncertain.

METHODS

We analyzed outcomes of patients treated on two consecutive frontline ALL protocols, using six different definitions of hyperdiploidy: chromosome number 51-67 (Chr51-67); DNA index (DI; DI1.16-1.6); United Kingdom ALL study group low-risk hyperdiploid, either trisomy of chromosomes 17 and 18 or +17 or +18 in the absence of +5 and +20; single trisomy of chromosome 18; double trisomy of chromosomes 4 and 10; and triple trisomy (TT) of chromosomes 4, 10, and 17. Additionally, we characterized ALL ex vivo pharmacotypes across eight main cytotoxic drugs.

RESULTS

Among 1,096 patients analyzed, 915 had B-ALL and 634 had pharmacotyping performed. In univariate analysis, TT emerged as the most favorable criterion for event-free survival (EFS; 10-year EFS, 97.3% v 86.8%; P = .0003) and cumulative incidence of relapse (CIR; 10-year CIR, 1.4% v 8.8%; P = .002) compared with the remaining B-ALL. In multivariable analysis, accounting for patient numbers using the akaike information criterion (AIC), DI1.16-1.6 was the most favorable criterion, exhibiting the best AIC for both EFS (hazard ratio [HR], 0.45; 95% CI, 0.23 to 0.88) and CIR (HR, 0.45; 95% CI, 0.21 to 0.99). Hyperdiploidy and subgroups with favorable prognoses exhibited notable sensitivities to asparaginase and mercaptopurine. Specifically, asparaginase sensitivity was associated with trisomy of chromosomes 16 and 17, whereas mercaptopurine sensitivity was linked to gains of chromosomes 14 and 17.

CONCLUSION

Among different definitions of hyperdiploid ALL, DI is optimal based on independent prognostic impact and also the large proportion of low-risk patients identified. Hyperdiploid ALL exhibited particular sensitivities to asparaginase and mercaptopurine, with chromosome-specific associations.

Outcomes and prognostic factors of patients with Extranodal NK T cell lymphoma (ENKTL)

The staging, prognostication, and treatment of ENKTL has evolved over the years with better understanding of the disease biology. There is significant heterogeneity in the treatment followed across the world. Literature from India have been few with small number of patients. We studied the outcomes and prognostic factors of patients with ENKTL treated between May 2010 and December 2021 at our center. A total of 78 patients diagnosed with ENKTL were treated at our center. L-asparaginase based chemotherapy was administered in 84% of the patients. Close to 2/3rd patients received SMILE chemotherapy. After a median follow-up of 30 months (18.5-41.4 months), the median relapse free survival and overall survival for the overall population was 45 months (12-118 months) and 45 months (14-118 months) respectively. By multivariate analysis, PINK score of 2-4, non-receipt of RT and non-achievement of CR were associated with poor survival.

Utility of ASNS gene methylation evaluated with the HPLC method as a pharmacogenomic biomarker to predict asparaginase sensitivity in BCP-ALL

Asparaginase is an important agent for the treatment of acute lymphoblastic leukaemia (ALL), but it is occasionally associated with severe adverse events. Thus, for safer and more efficacious therapy, a clinical biomarker predicting asparaginase sensitivity is highly anticipated. Asparaginase depletes serum asparagine by deaminating asparagine into aspartic acid, and ALL cells are thought to be sensitive to asparaginase due to reduced asparagine synthetase (ASNS) activity. We have recently shown that allele-specific methylation of the ASNS gene is highly involved in asparaginase sensitivity in B-precursor ALL (BCP-ALL) by using next-generation sequence (NGS) analysis of bisulphite PCR products of the genomic DNA. Here, we sought to confirm the utility of methylation status of the ASNS gene evaluated with high-performance liquid chromatography (HPLC) analysis of bisulphite PCR products for future clinical applications. In the global methylation status of 23 CpG sites at the boundary region of promoter and exon 1 of the ASNS gene, a strong positive correlation was confirmed between the mean percent methylation evaluated with the HPLC method and that with the NGS method in 79 BCP-ALL cell lines (R2 = 0.85, p = 1.3 × 10-33) and in 63 BCP-ALL clinical samples (R2 = 0.84, p = 5.0 × 10-26). Moreover, methylation status of the ASNS gene evaluated with the HPLC method was significantly associated with in vitro asparaginase sensitivities as well as gene and protein expression levels of ASNS. These observations indicated that the ASNS gene methylation status evaluated with the HPLC method is a reliable biomarker for predicting the asparaginase sensitivity of BCP-ALL.

Asparaginase dosing for obese patients with acute lymphoblastic leukemia and factors that contribute to outcomes

Asparaginase in various forms is a standard part of the treatment of acute lymphoblastic leukemia (ALL) in children and adolescents. However, its use is more selective in adults. One of the key reasons is the toxicity observed from this class of agents. In a series of recent post hoc analyses of large prospective studies, obesity has emerged as a key factor that contributes to the challenges with administering regimens that include asparaginase. In this review, the most salient findings are highlighted from these latest publications, both from the pediatric and adult literature. These data are consolidated into recommendations for clinicians who treat adults with ALL, including proposals for how treatment may be modified to try to account for these complications. Lastly, avenues for future investigation are proposed in an attempt to narrow our knowledge gaps in this field, with the goal of safer and more effective treatment for adults with obesity who develop ALL.

Comparative analysis of clinicopathologic characteristics and prognosis between nasal and nonnasal extranodal NK/T-cell lymphoma

BACKGROUND

The clinicopathologic characteristics and prognosis of nasal and nonnasal extranodal natural killer T-cell lymphoma (ENKTL) are considered to be different. However, the underlying features responsible for these differences are not well clarified especially in the era of asparaginase therapy.

METHODS

In total, 1007 newly diagnosed ENKTL patients from 11 medical centers were included in this study. Clinicopathologic characteristics and survival data were collected. The chi-squared test and Kruskal-Wallis test were utilized for the comparison of different groups. Univariable and multivariable Cox proportional hazards models were used to screen prognostic factors.

RESULTS

Overall, 869 (86.3%) patients were nasal forms. Compared to patients with nasal ENKTL, nonnasal patients were at more advanced stages and had poor performance status, bone marrow involvement, elevated serum lactate dehydrogenase (LDH), and CD56-negative status (p < 0.05). The 5-year overall survival (OS) for nasal and nonnasal patients were 65.6% and 45.0%, respectively. The OS of nasal forms patients were superior to nonnasal patients, especially in Eastern Cooperative Oncology Group performance status (ECOG PS) (≥2), advanced stage, KPI (HIR/HR), IPI (HIR/HR), PINK (HR), and high EBV DNA load groups. In patients treated with pegaspargase/L-asparaginase-based regimens, the OS of nasal patients was better than that of nonnasal patients. After adjusting the covariates of age, stage, ECOG PS score, LDH, B symptoms, and BM involvement, results showed that the nonnasal site was associated with poor survival of ENKTL.

CONCLUSIONS

The clinicopathologic characteristics and prognosis of nasal and nonnasal ENKTL patients are different. Nasal forms patients had superior OS than nonnasal patients, especially in the era of asparaginase.

Enzyme Engineering Strategies for the Bioenhancement of L-Asparaginase Used as a Biopharmaceutical

Over the past few years, there has been a surge in the industrial production of recombinant enzymes from microorganisms due to their catalytic characteristics being highly efficient, selective, and biocompatible. L-asparaginase (L-ASNase) is an enzyme belonging to the class of amidohydrolases that catalyzes the hydrolysis of L-asparagine into L-aspartic acid and ammonia. It has been widely investigated as a biologic agent for its antineoplastic properties in treating acute lymphoblastic leukemia. The demand for L-ASNase is mainly met by the production of recombinant type II L-ASNase from Escherichia coli and Erwinia chrysanthemi. However, the presence of immunogenic proteins in L-ASNase sourced from prokaryotes has been known to result in adverse reactions in patients undergoing treatment. As a result, efforts are being made to explore strategies that can help mitigate the immunogenicity of the drug. This review gives an overview of recent biotechnological breakthroughs in enzyme engineering techniques and technologies used to improve anti-leukemic L-ASNase, taking into account the pharmacological importance of L-ASNase.

Back to the future: the amazing journey of the therapeutic anti-leukemia enzyme asparaginase Erwinia chrysanthemi

For several decades, asparaginase has been considered world-wide as an essential component of combination chemotherapy for the treatment of childhood acute lymphoblastic leukemia (ALL). Discovered over 60 years ago, two main unmanipulated asparaginase products originated from primary bacteria sources, namely Escherichia coli and Erwinia chrysanthemi, have been available for clinical use. A pegylated product of the Escherichia coli asparaginase was subsequently developed and is now the main product used by several international co-operative groups. The various asparaginase products all display the same mechanism of action (hydrolysis of circulating asparagine) and are associated with similar efficacy and toxicity patterns. However, their different pharmacokinetics, pharmacodynamics and immunological properties require distinctive modalities of application and monitoring. Erwinia chrysanthemi asparaginase was initially used as a first-line product, but subsequently became a preferred second-line product for children who experienced immunological reactions to the Escherichia coli asparaginase products. An asparaginase product displaying the same characteristics of the Erwinia chrysanthemi asparaginase has recently been produced by use of recombinant technology, thus securing a preparation available for use as an alternative, or as a back-up in case of shortages, for the non-recombinant product. The long journey of the Erwinia chrysanthemi asparaginase product as it has developed throughout the last several decades has made it possible for almost every child and adult with ALL to complete the asparaginase-based protocol treatment when an immunological reaction has occurred to any Escherichia coli asparaginase product.

Rituximab administration in pediatric patients with newly diagnosed acute lymphoblastic leukemia

Polyethylene glycol (PEG)-asparaginase (pegaspargase) is a key agent in chemotherapy for acute lymphoblastic leukemia (ALL), but recipients frequently experience allergic reactions. We hypothesized that by decreasing antibody-producing CD20-positive B cells, rituximab may reduce these reactions. Children and adolescents (aged 1-18 years) with newly diagnosed B-ALL treated on the St. Jude Total XVII study were randomized to induction therapy with or without rituximab on day 3 (cohort 1) or on days 6 and 24 (cohort 2). Patient clinical demographics, CD20 expression, minimal residual disease (MRD), rituximab reactions, pegaspargase allergy, anti-pegaspargase antibodies, and pancreatitis were evaluated. Thirty-five patients received rituximab and 37 did not. Among the 35 recipients, 16 (45.7%) experienced a grade 2 or higher reaction to rituximab. There were no differences between recipients and non-recipients in the incidence of pegaspargase reactions (P  >  0.999), anti-pegaspargase antibodies (P  =  0.327), or pancreatitis (P  =  0.480). CD20 expression on day 8 was significantly lower in rituximab recipients (P  <  0.001), but there were no differences in MRD levels on day 8, 15, or at the end of induction. Rituximab administration during induction in pediatric patients with B-ALL was associated with a high incidence of infusion reactions with no significant decrease in pegaspargase allergies, anti-pegaspargase antibodies, or MRD.

Pegylated-l-asparaginase therapy for feline large cell lymphoma: 82 cases (2017-2020)

OBJECTIVES

The present study aimed to investigate pegylated-l-asparaginase monotherapy for feline large cell lymphoma as a potential alternative to palliative corticosteroids treatment in animals whose owners declined cytotoxic chemotherapy.

METHODS

A retrospective, descriptive case series of cats treated initially with pegylated-l-asparaginase as a sole therapy for feline large cell lymphoma is reported. The treatment protocol consisted of 12 intramuscular injections of pegylated-l-asparaginase with increasing intervals. If cats were unresponsive to pegylated-l-asparaginase monotherapy, a second-line treatment was initiated. Signalment, origin of lymphoma, staging, treatment, possible adverse events and follow-up data were extracted from the medical records. Responses and survival data were analysed.

RESULTS

Eighty-two cats with lymphoma of five different anatomic types were included: alimentary, abdominal extra-alimentary, peripheral nodal, nasal/nasopharyngeal and other (mediastinal, renal [solitary] and miscellaneous combined in one group for analytical purposes). The response rate was 74.1% (95% confidence interval = 63.4-83.5) with 38.3% (95% confidence interval = 27.8-48.8) in complete remission. The median disease-free period and calculated overall survival time were 70 days (12-1702+) and 79 days (1-1715+), respectively. The response rate was significantly correlated with the origin of the lymphoma and the combined group had a significantly lower response rate (P = 0.035). Twenty-four cats were also treated with corticosteroids. There was no significant difference in outcomes between the group treated with or without corticosteroids. Adverse events were present in a small number of cats (14/82). The majority of these adverse events were mild to moderate in 5/14 cats; however, the adverse events were severe enough to cause discontinuation of therapy.

CONCLUSIONS AND RELEVANCE

Based on the response rate and median disease-free period, treatment with pegylated-l-asparaginase is inferior when compared with historical chemotherapy protocols. However, some cats demonstrated an exceptional long disease-free period. Therefore, pegylated-l-asparaginase could be offered as an alternative to corticosteroid therapy alone. Further studies are needed to evaluate the additional benefit over palliative corticosteroid monotherapy.

[Analysis of prognostic factors of extranodal NK/T-cell lymphoma treated with pegaspargase/L-asparaginase: a multicenter retrospective study]

Objective: To explore the prognostic factors of extracellular NK/T cell lymphoma (ENKTL) treated with pegaspargase/L-asparaginase. Methods: The clinical data of 656 ENKTL patients diagnosed at 11 medical centers in the Huaihai Lymphoma Working Group from March 2014 to April 2021 were retrospectively analyzed. The patients were randomly divided into two groups: a training set (460 cases) and a validation set (196 cases) at 7∶3, and the prognostic factors of the patients were analyzed. A prognostic scoring system was established, and the predictive performance of different models was compared. Results: Patients' median age was 46 (34, 57) years, with 456 males (69.5% ) and 561 nasal involvement (85.5% ). 203 patients (30.9% ) received a chemotherapy regimen based on L-asparaginase combined with anthracyclines, and the 5-year overall survival rate of patients treated with P-GEMOX regimen (pegaspargase+gemcitabine+oxaliplatin) was better than those treated with SMILE regimen (methotrexate+dexamethasone+cyclophosphamide+L-asparaginase+etoposide) (85.9% vs 63.8% ; P=0.004). The results of multivariate analysis showed that gender, CA stage, the Eastern Cooperative Oncology Group performance status (ECOG PS) score, HGB, and EB virus DNA were independent influencing factors for the prognosis of ENKTL patients (P<0.05). In this study, the predictive performance of the prognostic factors is superior to the international prognostic index, Korean prognostic index, and prognostic index of natural killer lymphoma. Conclusion: Gender, CA stage, ECOG PS score, HGB, and EB virus DNA are prognostic factors for ENKTL patients treated with pegaspargase/L-asparaginase.

Thermoresponsive Polypeptide Fused L-Asparaginase with Mitigated Immunogenicity and Enhanced Efficacy in Treating Hematologic Malignancies

L-Asparaginase (ASP) is well-known for its excellent efficacy in treating hematological malignancies. Unfortunately, the intrinsic shortcomings of ASP, namely high immunogenicity, severe toxicity, short half-life, and poor stability, restrict its clinical usage. Poly(ethylene glycol) conjugation (PEGylation) of ASP is an effective strategy to address these issues, but it is not ideal in clinical applications due to complex chemical synthesis procedures, reduced ASP activity after conjugation, and pre-existing anti-PEG antibodies in humans. Herein, the authors genetically engineered an elastin-like polypeptide (ELP)-fused ASP (ASP-ELP), a core-shell structured tetramer predicted by AlphaFold2, to overcome the limitations of ASP and PEG-ASP. Notably, the unique thermosensitivity of ASP-ELP enables the in situ formation of a sustained-release depot post-injection with zero-order release kinetics over a long time. The in vitro and in vivo studies reveal that ASP-ELP possesses increased activity retention, improved stability, extended half-life, mitigated immunogenicity, reduced toxicity, and enhanced efficacy compared to ASP and PEG-ASP. Indeed, ASP-ELP treatment in leukemia or lymphoma mouse models of cell line-derived xenograft (CDX) shows potent anti-cancer effects with significantly prolonged survival. The findings also indicate that artificial intelligence (AI)-assisted genetic engineering is instructive in designing protein-polypeptide conjugates and may pave the way to develop next-generation biologics to enhance cancer treatment.

Endophytic Fungi as a Promising Source of Anticancer L-Asparaginase: A Review

L-asparaginase is a tetrameric enzyme from the amidohydrolases family, that catalyzes the breakdown of L-asparagine into L-aspartic acid and ammonia. Since its discovery as an anticancer drug, it is used as one of the prime chemotherapeutic agents to treat acute lymphoblastic leukemia. Apart from its use in the biopharmaceutical industry, it is also used to reduce the formation of a carcinogenic substance called acrylamide in fried, baked, and roasted foods. L-asparaginase is derived from many organisms including plants, bacteria, fungi, and actinomycetes. Currently, L-asparaginase preparations from Escherichia coli and Erwinia chrysanthemi are used in the clinical treatment of acute lymphoblastic leukemia. However, they are associated with low yield and immunogenicity problems. At this juncture, endophytic fungi from medicinal plants have gained much attention as they have several advantages over the available bacterial preparations. Many medicinal plants have been screened for L-asparaginase producing endophytic fungi and several studies have reported potent L-asparaginase producing strains. This review provides insights into fungal endophytes from medicinal plants and their significance as probable alternatives for bacterial L-asparaginase.

PEG-asparaginase treatment regimens for acute lymphoblastic leukaemia in children: a network meta-analysis

BACKGROUND

Asparaginase has played a crucial role in the improvement of survival in children with acute lymphoblastic leukaemia (ALL), which is the commonest cancer among children. Survival rates have steadily increased over decades since the introduction of asparaginase to ALL therapy, and overall survival rates reach 90% with the best contemporary protocols. Currently, polyethylene glycolated native Escherichia coli-derived L-asparaginase (PEG-asparaginase) is the preferred first-line asparaginase preparation. Besides its clinical benefits, PEG-asparaginase is well known for severe toxicities. Agreement on the optimal dose, treatment duration, and frequency of administration has never been reached among clinicians.

OBJECTIVES

Primary objective To assess the effect of the number of PEG-asparaginase doses on survival and relapse in children and adolescents with ALL. Secondary objectives To assess the association between the number of doses of PEG-asparaginase and asparaginase-associated toxicities (e.g. hypersensitivity, thromboembolism, pancreatitis and osteonecrosis). To undertake a network meta-analysis at dose-level in order to generate rankings of the number of doses of PEG-asparaginase used in the treatment for ALL, according to their benefits (survival and relapse) and harms (toxicity).

SEARCH METHODS

We searched CENTRAL, PubMed, Embase, Web of Science databases and three trials registers in November 2021, together with reference checking, citation searching and contact with study authors to identify additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing different PEG-asparaginase treatment regimens in children and adolescents (< 18 years of age) with first-line ALL treated with multiagent chemotherapy including PEG-asparaginase.

DATA COLLECTION AND ANALYSIS

Using a standardised data collection form, two review authors independently screened and selected studies, extracted data, assessed risk of bias for each outcome using a standardised tool (RoB 2.0) and assessed the certainty of evidence for each outcome using the GRADE approach. Primary outcomes included overall survival, event-free survival and leukaemic relapse. Secondary outcomes included asparaginase-associated toxicities (hypersensitivity, thromboembolism, pancreatitis, sinusoidal obstruction syndrome and osteonecrosis as well as overall asparaginase-associated toxicity). We conducted the review and performed the analyses in accordance with the guidelines of the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

We included three RCTs in the review, and identified an additional four ongoing studies. We judged outcomes of two RCTs to be at low risk of bias in all the Cochrane risk of bias (RoB 2) domains. We rated the remaining study as having some concerns regarding bias. Due to concerns about imprecision, we rated all outcomes as having low- to moderate-certainty evidence.  One study compared intermittent PEG-asparaginase treatment (eight doses of PEG-asparaginase, 1000 IU/m2, intramuscular (IM) administration) versus continuous PEG-asparaginase treatment (15 doses of PEG-asparaginase, 1000 IU/m2, IM) in 625 participants with non-high risk ALL aged 1.0 to 17.9 years. We found that treatment with eight doses probably results in little to no difference in event-free survival compared to treatment with 15 doses (RR 1.01, 95% CI 0.97 to 1.06; moderate-certainty evidence). Compared to treatment with 15 doses, treatment with eight doses may result in either no difference or a slight reduction in hypersensitivity (RR 0.64, 95% CI 0.21 to 1.93; low-certainty evidence), thromboembolism (RR 0.55, 95% CI 0.22 to 1.36; low-certainty evidence) or osteonecrosis (RR 0.68, 95% CI 0.35 to 1.32; low-certainty evidence). Furthermore, we found that treatment with eight doses probably reduces pancreatitis (RR 0.31, 95% CI 0.12 to 0.75; moderate-certainty evidence) and asparaginase-associated toxicity (RR 0.53, 95% CI 0.35 to 0.78; moderate-certainty evidence) compared to treatment with 15 doses. One study compared low-risk standard treatment with additional PEG-asparaginase (six doses, 2500 IU/m2, IM) versus low-risk standard treatment (two doses, 2500 IU/m2, IM) in 1857 participants aged one to nine years old with standard low-risk ALL. We found that, compared to treatment with two doses, treatment with six doses probably results in little to no difference in overall survival (RR 0.99, 95% CI 0.98 to 1.00; moderate-certainty evidence) and event-free survival (RR 1.01, 95% CI 0.99 to 1.04; moderate-certainty evidence), and may result in either no difference or a slight increase in osteonecrosis (RR 1.65, 95% CI 0.91 to 3.00; low-certainty evidence). Furthermore, we found that treatment with six doses probably increases hypersensitivity (RR 12.05, 95% CI 5.27 to 27.58; moderate-certainty evidence), pancreatitis (RR 4.84, 95% CI 2.15 to 10.85; moderate-certainty evidence) and asparaginase-associated toxicity (RR 4.49, 95% CI 3.05 to 6.59; moderate-certainty evidence) compared to treatment with two doses. One trial compared calaspargase (11 doses, 2500 IU/m2, intravenous (IV)) versus PEG-asparaginase (16 doses, 2500 IU/m2, IV) in 239 participants aged one to 21 years with standard- and high-risk ALL and lymphoblastic lymphoma. We found that treatment with 11 doses of calaspargase probably results in little to no difference in event-free survival compared to treatment with 16 doses of PEG-asparaginase (RR 1.06, 95% CI 0.97 to 1.16; moderate-certainty evidence). However, treatment with 11 doses of calaspargase probably reduces leukaemic relapse compared to treatment with 16 doses of PEG-asparaginase (RR 0.32, 95% CI 0.12 to 0.83; moderate-certainty evidence). Furthermore, we found that treatment with 11 doses of calaspargase results in either no difference or a slight reduction in hypersensitivity (RR 1.17, 95% CI 0.64 to 2.13; low-certainty evidence), pancreatitis (RR 0.85, 95% CI 0.47 to 1.52; low-certainty evidence), thromboembolism (RR 0.83, 95% CI 0.48 to 1.42; low-certainty evidence), osteonecrosis (RR 0.63, 95% CI 0.15 to 2.56; low-certainty evidence) and asparaginase-associated toxicity (RR 1.00, 95% CI 0.71 to 1.40; low-certainty evidence) compared to treatment with 16 doses of PEG-asparaginase.

AUTHORS' CONCLUSIONS

We were not able to conduct a network meta-analysis, and could not draw clear conclusions because it was not possible to rank the interventions. Overall, we found that different numbers of doses of PEG-asparaginase probably result in little to no difference in event-free survival across all studies. In two studies, we found that a higher number of PEG-asparaginase doses probably increases pancreatitis and asparaginase-associated toxicities.

Protein re-surfacing of E. coli L-Asparaginase to evade pre-existing anti-drug antibodies and hypersensitivity responses

The optimal use of many biotherapeutics is restricted by Anti-drug antibodies (ADAs) and hypersensitivity responses which can affect potency and ability to administer a treatment. Here we demonstrate that Re-surfacing can be utilized as a generalizable approach to engineer proteins with extensive surface residue modifications in order to avoid binding by pre-existing ADAs. This technique was applied to E. coli Asparaginase (ASN) to produce functional mutants with up to 58 substitutions resulting in direct modification of 35% of surface residues. Re-surfaced ASNs exhibited significantly reduced binding to murine, rabbit and human polyclonal ADAs, with a negative correlation observed between binding and mutational distance from the native protein. Reductions in ADA binding correlated with diminished hypersensitivity responses in an in vivo mouse model. By using computational design approaches to traverse extended distances in mutational space while maintaining function, protein Re-surfacing may provide a means to generate novel or second line therapies for life-saving drugs with limited therapeutic alternatives.

Management Practices for Asparaginase-associated Coagulopathy: A Survey of Pediatric Oncologists

BACKGROUND

Coagulopathy and thrombosis are well-described complications of asparaginase therapy. However, treatment practices in pediatric hematology/oncology (PHO) patients vary widely as evidence-based guidelines for clinical management of these complications in this population are lacking.

OBJECTIVE

The objective of this study was to assess management practices of asparaginase-related coagulopathy by pediatric hematologist/oncologist attending physicians.

DESIGN/METHOD

Email survey sent to 2327 PHO physicians primarily practicing in the United States.

RESULTS

Two hundred eighty-five (12.2%) attending physicians completed the survey. Only 4.6% (n=13/285) routinely prescribe prophylactic anticoagulation during induction chemotherapy for leukemia. Slightly more than half (n=145/250, 50.9%) of all providers perform baseline coagulation studies. Most providers that were surveyed (n=185/285, 64.9%) only replete coagulant factors if the patient experiences bleeding or bruising. One hundred thirty (n=130/285, 45.6%) physicians replace low fibrinogen. The median fibrinogen replacement was 100 mg/dL (range: 40 to 200 mg/dL) with the median target of at least 100 mg/dL (range: 50 to 200 mg/dL). A minority of physicians (n=39/250, 13.7%) replace low antithrombin. The median antithrombin cutoff activity level was 60% (range: 40% to 100%) with a median target of 75% (range: 40% to 125%).

CONCLUSIONS

There is a significant variation in PHO physician practices for monitoring and management of asparaginase-associated hemostatic derangements. Evidence-based guidelines have the potential to standardize practices.

A prospective, open-label, randomised, parallel design study of 4 generic formulations of intramuscular L-asparaginase in childhood precursor B-cell acute lymphoblastic leukaemia (ALL)

AIMS

L-asparaginase is an essential medicine for childhood ALL. The quality of generic L-asparaginase available in India is a matter of concern. We compared four commonly used generic formulations of L-asparaginase in India.

MATERIALS AND METHODS

We conducted a prospective, open-label, randomised trial of four generic formulations of asparaginase for the treatment of patients with newly diagnosed intermediate-risk B-ALL. Patients were randomly assigned in a 1:1:1:1 ratio to receive generic asparaginase at a dose of at 10,000 IU/m 2 on days 9, 12, 15, and 18 of a 35-day cycle (Induction treatment). The primary end points were to determine the difference in the asparaginase activity and asparagine depletion. Historical patients who received L-asparaginase Medac (innovator) served as controls.

RESULTS

A total of 48 patients underwent randomization; 12 patients each in the four arms. Failure to achieve predefined activity threshold of 100 IU/L was observed in 9/40 samples of Generic A (22·5%), 23/40 of Generic B (57·5%), and 43/44 (98%) each of Generic C and D. All 27 samples from seven historical patients who were administered Medac had activity > 100 IU/L. The average activity was significantly higher for Genericm A, 154 (70·3, 285·4) IU/L followed by Generic B 84·5(44·2, 289·1) IU/L, Generic C 45(14·4, 58·4) IU/L, and Generic D 20·4(13, 35) IU/L. Only 6 patients had asparaginase activity > 100 IU/L on each of the four occasions (Generic A = 5; Generic B = 1), and none of them developed Anti-Asparaginase Antibodies (AAA). On the other hand, AAA was observed in 12/36 patients who had at least one level < 100 IU/L (P < 0·05): Generic A 3/5, Generic B = 3/9, Generic D (4/11), and Generic C (5/11).

CONCLUSION

Generic A and B had better trough asparaginase activity compared to Generic D and C. Overall, generic formulations had lower asparaginase activity which raises serious clinical concerns regarding their quality. Until strict regulatory enforcement improves the quality of these generics, dose adaptive approaches coupled with therapeutic drug monitoring need to be considered.

A systematic review of recent trends in research on therapeutically significant L-asparaginase and acute lymphoblastic leukemia

L-asparaginases are mostly obtained from bacterial sources for their application in the therapy and food industry. Bacterial L-asparaginases are employed in the treatment of Acute Lymphoblastic Leukemia (ALL) and its subtypes, a type of blood and bone marrow cancer that results in the overproduction of immature blood cells. It also plays a role in the food industry in reducing the acrylamide formed during baking, roasting, and frying starchy foods. This importance of the enzyme makes it to be of constant interest to the researchers to isolate novel sources. Presently L-asparaginases from E. coli native and PEGylated form, Dickeya chrysanthemi (Erwinia chrysanthemi) are in the treatment regime. In therapy, the intrinsic glutaminase activity of the enzyme is a major drawback as the patients in treatment experience side effects like fever, skin rashes, anaphylaxis, pancreatitis, steatosis in the liver, and many complications. Its significance in the food industry in mitigating acrylamide is also a major reason. Acrylamide, a potent carcinogen was formed when treating starchy foods at higher temperatures. Acrylamide content in food was analyzed and pre-treatment was considered a valuable option. Immobilization of the enzyme is an advancing and promising technique in the effective delivery of the enzyme than in free form. The concept of machine learning by employing the Artificial Network and Genetic Algorithm has paved the way to optimize the production of L-asparaginase from its sources. Gene-editing tools are gaining momentum in the study of several diseases and this review focuses on the CRISPR-Cas9 gene-editing tool in ALL.

Tumoral microenvironment prevents de novo asparagine biosynthesis in B cell lymphoma, regardless of ASNS expression

Depletion of circulating asparagine with l-asparaginase (ASNase) is a mainstay of leukemia treatment and is under investigation in many cancers. Expression levels of asparagine synthetase (ASNS), which catalyzes asparagine synthesis, were considered predictive of cancer cell sensitivity to ASNase treatment, a notion recently challenged. Using [U-¹³C₅]-l-glutamine in vitro and in vivo in a mouse model of B cell lymphomas (BCLs), we demonstrated that supraphysiological or physiological concentrations of asparagine prevent de novo asparagine biosynthesis, regardless of ASNS expression levels. Overexpressing ASNS in ASNase-sensitive BCL was insufficient to confer resistance to ASNase treatment in vivo. Moreover, we showed that ASNase's glutaminase activity enables its maximal anticancer effect. Together, our results indicate that baseline ASNS expression (low or high) cannot dictate BCL dependence on de novo asparagine biosynthesis and predict BCL sensitivity to dual ASNase activity. Thus, except for ASNS-deficient cancer cells, ASNase's glutaminase activity should be considered in the clinic.

How we treat NK/T-cell lymphomas

Natural killer (NK)/T-cell lymphomas are aggressive malignancies with a predilection for Asian and South American populations. Epstein-Barr virus (EBV) infection in lymphoma cells is universal. Predominantly extranodal, NK/T-cell lymphomas are divided clinically into nasal (involving the nose and upper aerodigestive tract), non-nasal (involving the skin, gastrointestinal tract, testes, and other organs), and aggressive leukaemia/lymphoma (involving the marrow and multiple organs) subtypes. Initial assessment should include imaging with positron emission tomography computed tomography (PET/CT), quantification of plasma EBV DNA as a surrogate marker of lymphoma load, and bone marrow examination with in situ hybridization for EBV-encoded small RNA. Prognostication can be based on presentation parameters (age, stage, lymph node involvement, clinical subtypes, and EBV DNA), which represent patient factors and lymphoma load; and dynamic parameters during treatment (serial plasma EBV DNA and interim/end-of-treatment PET/CT), which reflect response to therapy. Therapeutic goals are to achieve undetectable plasma EBV DNA and normal PET/CT (Deauville score ≤ 3). NK/T-cell lymphomas express the multidrug resistance phenotype, rendering anthracycline-containing regimens ineffective. Stage I/II nasal cases are treated with non-anthracycline asparaginase-based regimens plus sequential/concurrent radiotherapy. Stage III/IV nasal, and non-nasal and aggressive leukaemia/lymphoma cases are treated with asparaginase-containing regimens and consolidated by allogeneic haematopoietic stem cell transplantation (HSCT) in suitable patients. Autologous HSCT does not improve outcome. In relapsed/refractory cases, novel approaches comprise immune checkpoint blockade of PD1/PD-L1, EBV-specific cytotoxic T-cells, monoclonal antibodies, and histone deacetylase inhibitors. Future strategies may include inhibition of signalling pathways and driver mutations, and immunotherapy targeting the lymphoma and its microenvironment.

Characterization of the impact of the MYBBP1A gene and rs3809849 on asparaginase sensitivity and cellular functions

Aims: To investigate the role of MYBBP1A gene and rs3809849 in pancreatic cancer (PANC1) and lymphoblastic leukemia (NALM6) cell lines and their response to asparaginase treatment. Materials & methods: The authors applied CRISPR-Cas9 to produce MYBBP1A knock-out (KO) and rs3809849 knock-in (KI) cell lines. The authors also interrogated rs3809849's impact on PANC1 cells through allele-specific overexpression. Results: PANC1 MYBBP1A KO cells exhibited lower proliferation capacity (p ≤ 0.05), higher asparaginase sensitivity (p = 0.01), reduced colony-forming potential (p = 0.001), cell cycle blockage in S phase, induction of apoptosis and remarkable morphology changes suggestive of an epithelial-mesenchymal transition. Overexpression of the wild-type (but not the mutant) allele of MYBBP1A-rs3809849 in PANC1 cells increased asparaginase sensitivity. NALM6 MYBBP1A KO displayed resistance to asparaginase (p < 0.0001), whereas no effect for rs3809849 KI was noted. Conclusions:MYBBP1A is important for regulating various cellular functions, and it plays, along with its rs3809849 polymorphism, a tissue-specific role in asparaginase treatment response.

Plant asparaginase versus microbial asparaginase as anticancer agent

The considerable effect of enzymes on human health draws great attention to enzyme-based drugs (therapeutic enzymes), in recent times. L-asparaginase (ASNase) is a well-known therapeutic enzyme. It has varied applications and is a single molecule for the treatment of multiple diseases. This study tries to extract asparaginase from soybean debris (agricultural wastes) as a cheap plant source and compare this with microbial asparaginase as an agent in cancer chemotherapy. The asparaginase was extracted and purified from soybean debris (plant asparaginase) and Pseudomonas aeruginosa (microbial asparaginase), then the physiochemical characters were determined for the two enzymes, and the anticancer activity of plant and microbial asparaginase was determined against gastric cancer (CLS-145), pancreatic cancer (AsPC-1), colon cancer (HCT116), esophagus cancer (KYSE-410), liver cancer (HepG2), breast cancer (MCF-7), and cervical cancer (HELLA). The results showed that plant asparaginase was superior to microbial asparaginase in its physiochemical characters. Plant asparaginase showed higher stability and activity under the conditions of changing either the temperature or the pH; also plant asparaginase has a higher affinity to the asparagine than the microbial asparaginase; besides, this plant asparaginase did not show activity with glutamine as a substrate. The plant asparaginase showed higher anticancer activity than that of microbial asparaginase against all studied cancer cell lines. The present study introduces as the first time a comparative study between the plant and microbial asparaginase which proves that soybean debris asparaginase can be more efficient and safe than that of the microbial asparaginase as an anticancer agent.

CD56-Negative Extranodal Natural Killer/T-Cell Lymphoma: A Retrospective Study in 443 Patients Treated by Chemotherapy With or Without Asparaginase

Objective

Extranodal natural killer/T cell lymphoma (NKTCL) is an aggressive EBV-related lymphoma, originating from NK cells or T cells. Previous study demonstrated that CD56 negative NKTCL should be recognized as a distinct subtype. In this study, the value of CD56 in NKTCL is validated in the era of asparaginase, and genomic analysis was done to dissect the differences between CD56-negative and positive NKTCL.

Methods

443 patients with newly diagnosed NKTCL were enrolled in this retrospective study, and correlation between CD56 positivity and survival outcomes was analyzed. The gene sequencing data was downloaded (http://www.biosino.org/node/project/detail/OEP000498), and bioinformatics analysis was done to delineate the tumor microenvironment and differentially expressed genes.

Results

CD56 was expressed in 337 patients (76.1%). Within a median follow-up time of 51 months, the 5-year overall survival (OS) and progression free survival (PFS) rates were 63.8% and 51.9%, respectively. For the whole cohort, patients who were CD56-positive had superior OS (5-year OS, 86.2% vs. 51.9%, p=0.019) and PFS (5-year PFS, 55.9% vs. 40.1%, p=0.016). For patients in early stage disease, CD56 positivity was associated with superior OS and PFS (p=0.008 and 0.005, respectively). In patients who received non-asparaginase-based chemotherapy, CD56-negative was associated with shorter OS and PFS (p&lt;0.001), and in patients who received asparaginase-based chemotherapy, CD56-negative was not related to inferior OS and PFS (p=0.093 and p=0.829, respectively). The genomic analysis demonstrated that CD56 positive NKTCL probably originated from NK cells and CD56 negative NKTCL originated from T cells. CD56 positive NKTCL had significantly higher proportion of resting NK cells, activated NK cells, and activated CD8+ and CD4+ T cells in the tumor microenvironment.

Conclusions

CD56 negative NKTCL differs from CD56 positive NKTCL in both the tumor microenvironment and survival outcomes, and asparaginase-based treatment may overcome the poor prognosis brought by CD56 negativity.

Combination of Anti-PD-1 Antibody, Anlotinib and Pegaspargase “Sandwich” With Radiotherapy in Localized Natural Killer/T Cell Lymphoma

Asparaginase/pegaspargase containing regimens combined with radiotherapy are highly effective and considered the cornerstone of localized Natural killer/T-cell lymphoma (NKTL) treatment. However, these chemotherapy regimens inevitably cause relatively high incidence of treatment-related adverse events (TRAEs). Herein we retrospectively evaluated the efficacy and safety of the combined regimen of anti-PD-1 antibody, anlotinib and pegaspargase “sandwich” with radiotherapy in localized NKTL. Anti-PD-1 antibody and pegaspargase at 2500 U/m² were administered on day 1, while anlotinib (12 mg once a day) was orally administered on days 1-14. The treatment was repeated every 3 weeks. All the eight patients included received 3 cycles of the regimen followed by radiotherapy and an additional 3 cycles. The overall response rate was 100%, and the complete response rate was 87.5%. With a median follow-up time of 35.5 months (range, 34.03-40.90 months), median PFS and OS times were not reached. The 3-year PFS and OS rates were 100% and 100%, respectively. All patients were alive at the last follow-up. No treatment-related death and no grade 4 TRAE was reported. No grade 3/4 hematological toxicity was detected, and half of the patients didn’t report any hematological toxicity. This study indicates that anti-PD-1 antibody combined with anlotinib and pegaspargase is a promising chemoradiotherapy regimen for localized NTKL, with mild toxicity and good tolerance.

[Extranodal NK/T cell lymphoma, nasal type with local recurrence in the contralateral nasal cavity 15 years after initial sequential chemoradiotherapy]

A 72-year-old woman was diagnosed with extranodal NK/T cell lymphoma of the right nasal cavity and received sequential radiochemotherapy comprising focal radiotherapy and THP-COP chemotherapy. Showed a complete tumor response to the treatment; however, the tumor recurred in the contralateral right nasal cavity 15 years after the initial treatment. This was judged to be a marginal recurrence in the radiation field. After four cycles of dexamethasone, methotrexate, ifosfamide, L-asparaginase, and etoposide (SMILE) chemotherapy, a second complete response was achieved. It is possible that another recurrence occurs in the future, and if the lesion is localized at the time of recurrence, it may be possible to control the disease again. Careful follow-up is considered necessary.

[Treatment strategy for T-cell acute lymphoblastic leukemia in children]

T-cell acute lymphoblastic leukemia (T-ALL) accounted for approximately 10-15% of pediatric ALL and has often been treated within the same framework as B-cell precursor ALL (BCP-ALL). T-ALL has a poorer prognosis than BCP-ALL. However, improvements have been achieved through treatment intensification strategies using dexamethasone, L-asparaginase, and nelarabine, thereby reducing cranial irradiation. Furthermore, T-ALL-specific treatment protocols have been introduced based on these advancements. The JPLSG ALL-T11/JALSG T-ALL-211-U trial in Japan has been conducted from 2011 to 2017 for newly diagnosed patients with T-ALL under the age of 25 years. The trial included minimal residual disease-based treatment stratification and treatment intensification as described above and has shown excellent outcomes. Recently, new therapeutic agents have been actively developed for T-ALL. Thus, targeted therapy development based on new findings is expected in the future.

The impact of the host intestinal microbiome on carcinogenesis and the response to chemotherapy

The microbiome consists of all microbes present on and within the human body. An unbalanced, or 'dysbiotic' intestinal microbiome is associated with inflammatory bowel disease, diabetes and some cancer types. Drug treatment can alter the intestinal microbiome composition. Additionally, some chemotherapeutics interact with microbiome components, leading to changes in drug safety and/or efficacy. The intestinal microbiome is a modifiable target, using strategies such as antibiotic treatment, fecal microbial transplantation or probiotic administration. Understanding the impact of the microbiome on the safety and efficacy of cancer treatment may result in improved treatment outcome. The present review seeks to summarize relevant research and look to the future of cancer treatment, where the intestinal microbiome is recognized as an actionable treatment target.

Time Course and Management of Protracted Anaphylaxis Due to PEG-Asparaginase

Polyethylene glycosylated (PEG)-asparaginase is a cornerstone of treatment for acute lymphoblastic leukemia (ALL), and effective administration is associated with better outcomes. PEG-asparaginase is associated with a uniphasic hypersensitivity reaction in ∼10% to 20% of patients. We present a 17-year-old male individual diagnosed with very high-risk pre-B-ALL, who experienced protracted anaphylaxis 1 hour following administration of his second PEG-asparaginase dose. This type of allergic reaction has yet to be described in ALL patients treated with PEG-asparaginase. Here, we outline the time course and successful management of protracted anaphylaxis in an ALL patient.

Altered FDG Biodistribution in Subcutaneous White Fat on PET/CT Following l-Asparaginase Chemotherapy

ABSTRACT

A 13-year-old boy with mediastinal T-cell lymphoblastic lymphoma demonstrated an altered biodistribution with diffuse activity in subcutaneous white adipose tissue and decreased visceral activity on interim posttreatment FDG PET/CT. This altered biodistribution was attributed to administration of the chemotherapeutic enzyme l-asparaginase 3 hours preceding the PET/CT, altering adipocytes amino acid and glucose metabolism. Treatment response assessment was adversely affected by the altered biodistribution, emphasizing the importance of maximizing the time between chemotherapy and PET/CT during successive oncologic treatment cycles. Because adipocytes protect leukemic cells in culture from l-asparaginase, we hypothesize that white adipose tissue-altered biodistribution may be related to l-asparaginase resistance.

Pre-existing antibodies against polyethylene glycol reduce asparaginase activities on first administration of pegylated E. coli asparaginase in children with acute lymphocytic leukemia

Antibodies against polyethylene glycol (PEG) in healthy subjects raise concerns about the efficacy of pegylated drugs. We evaluated the prevalence of antibodies against PEG among patients with acute lymphoblastic leukemia (ALL) prior to and/or immediately after their first dose of pegylated E.coli asparaginase (PEG-ASNase). Serum samples of 701 children, 673 with primary ALL, 28 with relapsed ALL, and 188 adults with primary ALL were analyzed for anti-PEG IgG and IgM. Measurements in 58 healthy infants served as reference to define cut-points for antibody-positive and -negative samples. Anti-PEG antibodies were detected in ALL patients prior the first PEG-ASNase with a prevalence of 13.9% (anti-PEG IgG) and 29.1% (anti-PEG IgM). After administration of PEG-ASNase the prevalence of anti-PEG antibodies decreased to 4.2% for anti-PEG IgG and to 4.5% for anti-PEG IgM. Pre-existing anti-PEG antibodies did not inhibit PEG-ASNase activity but significantly reduced PEGASNase activity levels in a concentration dependent manner. Although pre-existing anti-PEG antibodies did not boost, pre-existing anti-PEG IgG were significantly associated with firstexposure hypersensitivity reactions (CTCAE grade 2) (p

Dietary thiamine influences l-asparaginase sensitivity in a subset of leukemia cells

Tumor environment influences anticancer therapy response but which extracellular nutrients affect drug sensitivity is largely unknown. Using functional genomics, we determine modifiers of l-asparaginase (ASNase) response and identify thiamine pyrophosphate kinase 1 as a metabolic dependency under ASNase treatment. While thiamine is generally not limiting for cell proliferation, a DNA-barcode competition assay identifies leukemia cell lines that grow suboptimally under low thiamine and are characterized by low expression of solute carrier family 19 member 2 (SLC19A2), a thiamine transporter. SLC19A2 is necessary for optimal growth and ASNase resistance, when standard medium thiamine is lowered ~100-fold to human plasma concentrations. In addition, humanizing blood thiamine content of mice through diet sensitizes SLC19A2-low leukemia cells to ASNase in vivo. Together, our work reveals that thiamine utilization is a determinant of ASNase response for some cancer cells and that oversupplying vitamins may affect therapeutic response in leukemia.

Successful Outcomes of Newly Diagnosed T Lymphoblastic Lymphoma: Results From Children's Oncology Group AALL0434

PURPOSE

The 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 METHODS

The 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.

RESULTS

At 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.

CONCLUSION

COG 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.

Pegaspargase Combined with Concurrent Radiotherapy for Early-Stage Extranodal Natural Killer/T-Cell Lymphoma, Nasal Type: A Two-Center Phase II Study

Background

Concurrent chemoradiotherapy (CCRT) is expected to improve local and systemic disease control and has been established as a standard therapy for several types of solid tumors. Considering the benefits of frontline radiation and pegaspargase in localized extranodal natural killer (NK)/T‐cell lymphoma, nasal type (ENKTL), we conducted a phase II study on pegaspargase‐based CCRT to explore an effective treatment.

Materials and Methods

In this study, 30 patients with newly diagnosed nasal ENKTL in stages IE to IIE received CCRT (radiation 50 Gy and two cycles of pegaspargase 2,500 unit/m² every 3 weeks). Four courses of pegaspargase were performed after CCRT.

Results

The patients completed CCRT and four cycles of pegaspargase. The complete remission (CR) rate was 90%, with a 95% confidential interval (CI) of 73.5%–97.9% after CCRT. The CR rate was 100% (95% CI, 88.4%–100%) at the end of the treatment. The 2‐year overall survival and progression‐free survival rates were 90.9% (95% CI, 78.4%–100%) and 92.8% (95% CI, 83.2%–100%), respectively. The major adverse events were in grades 1–2.

Conclusion

Preliminary data indicate that pegaspargase combined with concurrent radiotherapy for newly diagnosed patients with nasal ENKTL was efficacious and well tolerated. Registered atwww.chictr.org. Clinical Trial Registration Number. ChiCTR‐OIC‐15007662.

Implications for Practice

This clinical trial, evaluating the efficacy and toxicity of concurrent chemoradiotherapy by using single‐drug pegaspargase for patients with extranodal natural killer/T‐cell lymphoma, nasal type (ENKTL) in stage IE to IIE, showed pegaspargase combined with concurrent radiotherapy was efficacious and well tolerated. Pegaspargase has a long half‐life and is easy to administer via intramuscular injection. Consequently, pegaspargase combined with concurrent radiotherapy for patients with ENKTL can be completed in the outpatient clinic.

This phase II clinical study evaluated the efficacy and toxicity of concurrent chemoradiotherapy using single‐drug pegaspargase for patients with nasal‐type extranodal NK/T‐cell lymphoma.

L-asparaginase-induced Parotitis in an Elderly Patient with Acute Lymphoblastic Leukemia

A 67-year-old woman received induction chemotherapy comprising vincristine, daunorubicin, cyclophosphamide, L-asparaginase and prednisolone for acute lymphoblastic leukemia with a common B-cell phenotype. The administration of L-asparaginase at 3,000 U/m² for 6 days was planned. Before the fourth administration on day 16, left parotid swelling was identified along with increased serum amylase (991 U/L; 94% derived from salivary glands). An enlarged left parotid gland was apparent on computed tomography. The symptoms resolved after cessation of L-asparaginase, with serum amylase normalizing by day 20. This rare adverse event should be recognized as improving within a week after ceasing L-asparaginase.