Publications by authors named "Jan Starý"

164 Publications

Population Pharmacokinetics of PEGylated Asparaginase in Children with Acute Lymphoblastic Leukemia: Treatment Phase Dependency and Predictivity in Case of Missing Data.

Eur J Drug Metab Pharmacokinet 2021 Feb 17. Epub 2021 Feb 17.

Department of Pediatric Hematology and Oncology, University Hospital Münster, Albert-Schweitzer-Campus 1, Building A1, 48149, Münster, Germany.

Background And Objectives: The pharmacokinetics of polyethylene glycol-conjugated asparaginase (PEG-ASNase) are characterized by an increase in elimination over time, a marked increase in ASNase activity levels from induction to reinduction, and high inter- and intraindividual variability. A population pharmacokinetic (PopPK) model is required to estimate individual dose intensity, despite gaps in monitoring compliance.

Methods: In the AIEOP-BFM ALL 2009 trial, two PEG-ASNase administrations (2500 U/m intravenously) during induction (14-day interval) and one administration during reinduction were administered in children with acute lymphoblastic leukemia. ASNase activity levels were monitored weekly. A PopPK model was used for covariate modeling and external validation. The predictivity of the model in case of missing data was tested for observations, as well as for the derived parameters of the area under the concentration time curve (AUC) and time above different thresholds.

Results: Compared to the first administration in induction (1374 patients, 6069 samples), the initial clearance and volume of distribution decreased by 11.0% and 15.9%, respectively, during the second administration during induction and by 41.2% and 28.4% during reinduction. Furthermore, the initial clearance linearly increased for children aged > 8 years and was 7.1% lower for females. The model was successfully externally validated (1253 patients, 5523 samples). In case of missing data, > 52% of the predictions for observations and > 82% for derived parameters were within ± 20% of the nominal value.

Conclusion: A PopPK model that describes the complex pharmacokinetics of PEG-ASNase was successfully externally validated. AUC or time above different thresholds, which are parameters describing dose intensity, can be estimated with high predictivity, despite missing data. ( www.clinicaltrials.gov , NCT01117441, first submitted date: May 3, 2010).
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s13318-021-00670-8DOI Listing
February 2021

Long non-coding RNAs as novel therapeutic targets in juvenile myelomonocytic leukemia.

Sci Rep 2021 Feb 2;11(1):2801. Epub 2021 Feb 2.

Department of Pediatric Hematology-Oncology and Stem Cell Transplantation, Ghent University Hospital, Ghent, Belgium.

Juvenile myelomonocytic leukemia (JMML) treatment primarily relies on hematopoietic stem cell transplantation and results in long-term overall survival of 50-60%, demonstrating a need to develop novel treatments. Dysregulation of the non-coding RNA transcriptome has been demonstrated before in this rare and unique disorder of early childhood. In this study, we investigated the therapeutic potential of targeting overexpressed long non-coding RNAs (lncRNAs) in JMML. Total RNA sequencing of bone marrow and peripheral blood mononuclear cell preparations from 19 untreated JMML patients and three healthy children revealed 185 differentially expressed lncRNA genes (131 up- and 54 downregulated). LNA GapmeRs were designed for 10 overexpressed and validated lncRNAs. Molecular knockdown (≥ 70% compared to mock control) after 24 h of incubation was observed with two or more independent GapmeRs in 6 of them. For three lncRNAs (lnc-THADA-4, lnc-ACOT9-1 and NRIR) knockdown resulted in a significant decrease of cell viability after 72 h of incubation in primary cultures of JMML mononuclear cells, respectively. Importantly, the extent of cellular damage correlated with the expression level of the lncRNA of interest. In conclusion, we demonstrated in primary JMML cell cultures that knockdown of overexpressed lncRNAs such as lnc-THADA-4, lnc-ACOT9-1 and NRIR may be a feasible therapeutic strategy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-021-82509-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7854679PMC
February 2021

CircRNAs Dysregulated in Juvenile Myelomonocytic Leukemia: CircMCTP1 Stands Out.

Front Cell Dev Biol 2020 6;8:613540. Epub 2021 Jan 6.

Department of Molecular Medicine, University of Padova, Padua, Italy.

Juvenile myelomonocytic leukemia (JMML), a rare myelodysplastic/myeloproliferative neoplasm of early childhood, is characterized by clonal growth of RAS signaling addicted stem cells. JMML subtypes are defined by specific RAS pathway mutations and display distinct gene, microRNA (miRNA) and long non-coding RNA expression profiles. Here we zoom in on circular RNAs (circRNAs), molecules that, when abnormally expressed, may participate in malignant deviation of cellular processes. CirComPara software was used to annotate and quantify circRNAs in RNA-seq data of a "discovery cohort" comprising 19 JMML patients and 3 healthy donors (HD). In an independent set of 12 JMML patients and 6 HD, expression of 27 circRNAs was analyzed by qRT-PCR. CircRNA-miRNA-gene networks were reconstructed using circRNA function prediction and gene expression data. We identified 119 circRNAs dysregulated in JMML and 59 genes showing an imbalance of the circular and linear products. Our data indicated also circRNA expression differences among molecular subgroups of JMML. Validation of a set of deregulated circRNAs in an independent cohort of JMML patients confirmed the down-regulation of circOXNAD1 and circATM, and a marked up-regulation of circLYN, circAFF2, and circMCTP1. A new finding in JMML links up-regulated circMCTP1 with known tumor suppressor miRNAs. This and other predicted interactions with miRNAs connect dysregulated circRNAs to regulatory networks. In conclusion, this study provides insight into the circRNAome of JMML and paves the path to elucidate new molecular disease mechanisms putting forward circMCTP1 up-regulation as a robust example.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fcell.2020.613540DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7815690PMC
January 2021

Clinical Implications of Minimal Residual Disease Detection in Infants With -Rearranged Acute Lymphoblastic Leukemia Treated on the Interfant-06 Protocol.

J Clin Oncol 2021 Feb 6;39(6):652-662. Epub 2021 Jan 6.

Princess Máxima Center for Pediatric Oncology, Utrecht, the Netherlands.

Purpose: Infant acute lymphoblastic leukemia (ALL) is characterized by a high incidence of gene rearrangements and poor outcome. We evaluated the value of minimal residual disease (MRD) in infants with -rearranged ALL treated within the Interfant-06 protocol, which compared lymphoid-style consolidation (protocol IB) versus myeloid-style consolidation (araC, daunorubicin, etoposide/mitoxantrone, araC, etoposide).

Materials And Methods: MRD was measured in 249 infants by DNA-based polymerase chain reaction of rearranged , immunoglobulin, and/or T-cell receptor genes, at the end of induction (EOI) and end of consolidation (EOC). MRD results were classified as negative, intermediate (< 5 × 10), and high (≥ 5 × 10).

Results: EOI MRD levels predicted outcome with 6-year disease-free survival (DFS) of 60.2% (95% CI, 43.2 to 73.6), 45.0% (95% CI, 28.3 to 53.1), and 33.8% (95% CI, 23.8 to 44.1) for infants with negative, intermediate, and high EOI MRD levels, respectively ( = .0039). EOC MRD levels were also predictive of outcome, with 6-year DFS of 68.2% (95% CI, 55.2 to 78.1), 40.1% (95% CI, 28.1 to 51.9), and 11.9% (95% CI, 2.6 to 29.1) for infants with negative, intermediate, and high EOC MRD levels, respectively ( < .0001). Analysis of EOI MRD according to the type of consolidation treatment showed that infants treated with lymphoid-style consolidation had 6-year DFS of 78.2% (95% CI, 51.4 to 91.3), 47.2% (95% CI, 33.0 to 60.1), and 23.2% (95% CI, 12.1 to 36.4) for negative, intermediate, and high MRD levels, respectively ( < .0001), while for myeloid-style-treated patients the corresponding figures were 45.0% (95% CI, 23.9 to 64.1), 41.3% (95% CI, 23.2 to 58.5), and 45.9% (95% CI, 29.4 to 60.9).

Conclusion: This study provides support for the idea that induction therapy selects patients for subsequent therapy; infants with high EOI MRD may benefit from AML-like consolidation (DFS 45.9% 23.2%), whereas patients with low EOI MRD may benefit from ALL-like consolidation (DFS 78.2% 45.0%). Patients with positive EOC MRD had dismal outcomes. These findings will be used for treatment interventions in the next Interfant protocol.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1200/JCO.20.02333DOI Listing
February 2021

Childhood cancer epidemiology in the Czech Republic (1994-2016).

Cancer Epidemiol 2020 Dec 19;69:101848. Epub 2020 Nov 19.

Institute of Biostatistics and Analyses, Faculty of Medicine, Masaryk University, Kamenice 126/3, 62500, Brno, Czech Republic; Institute of Health Information and Statistics of the Czech Republic, Palackeho namesti 4, 12801, Prague 2, Czech Republic.

Background: The knowledge of cancer burden in the population, its time trends and the possibility of international comparison is an important starting point for cancer control programmes. Our study aimed to evaluate trends in childhood cancer epidemiology of patients aged 0-14 years in the period 1994-2016 in the Czech Republic.

Methods: Data on childhood cancers have been obtained from the Czech National Cancer Registry. These data were validated using the clinical database of childhood cancer patients and combined with data from death certificates. Incidence and mortality trends were assessed by the joinpoint regression method. The life tables method was used to calculate the overall age-standardised five-year survival.

Results: The incidence trend was stable; the age-standardised (world) cancer incidence - ASR (W) - was 173.7 per 1 million children in the period 1994-2016. However, there was apparent significant decrease in mortality: ASR (W) dropped from 58.1 per 1 million children in 1994 to 21.4 per 1 million children in 2016. The overall five-year survival increased over time by 10 %. Statistically significant improvements in survival were observed in patients with lymphoid leukaemia, astrocytomas, neuroblastomas, osteosarcomas and rhabdomyosarcomas.

Conclusion: Such a relevant increase in survival rates, and therefore also a decrease in mortality rates in the Czech Republic, is most likely due to improvements in diagnostic and treatment methods since the 1990s, which were facilitated by the concentration of childhood cancer patients in children's cancer centres.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.canep.2020.101848DOI Listing
December 2020

Blast clearance after one week of corticosteroids correlates with outcome and genetics but does not justify adding a residual disease time point in acute lymphoblastic leukemia treatment.

Leuk Lymphoma 2020 Oct 29:1-3. Epub 2020 Oct 29.

Department of Paediatric Haematology and Oncology, Charles University, Second Faculty of Medicine, CLIP, Prague, Czech Republic.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/10428194.2020.1839659DOI Listing
October 2020

Rapidly progressing acute myeloid leukemia with KAT6A-LEUTX fusion in a newborn.

Pediatr Blood Cancer 2020 10 11;67(10):e28663. Epub 2020 Aug 11.

Department of Pediatric Hematology and Oncology, Second Faculty of Medicine, Charles University and University Hospital Motol, Prague, Czech Republic.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/pbc.28663DOI Listing
October 2020

DUX4r, ZNF384r and PAX5-P80R mutated B-cell precursor acute lymphoblastic leukemia frequently undergo monocytic switch.

Haematologica 2020 07 9. Epub 2020 Jul 9.

CLIP-Dpt.of Paediatric Haematology/Oncology, Charles University, Prague, Czech Republic;

Recently, we described B-cell precursor acute lymphoblastic leukemia (BCP-ALL) subtype with early switch to the monocytic lineage and loss of the B-cell immunophenotype, including CD19 expression. Thus far, the genetic background has remained unknown. Among 726 children consecutively diagnosed with BCP-ALL, 8% patients experienced switch detectable by flow cytometry (FC). Using exome and RNA sequencing, switch was found to positively correlate with three different genetic subtypes: PAX5-P80R mutation (5 cases with switch out of 5), rearranged DUX4 (DUX4r; 30 cases of 41) and rearranged ZNF384 (ZNF384r; 4 cases of 10). Expression profiles or phenotypic patterns correlated with genotypes, but within each genotype they could not identify cases who subsequently switched. If switching was not taken into account, the B-cell-oriented FC assessment underestimated the minimal residual disease level. For patients with PAX5-P80R, a discordance between FC-determined and PCR-determined MRD was found on day 15, resulting from a rapid loss of the B-cell phenotype. Discordance on day 33 was observed in all the DUX4r, PAX5-P80R and ZNF384r subtypes. Importantly, despite the substantial phenotypic changes, possibly even challenging the appropriateness of BCP-ALL therapy, the monocytic switch was not associated with a higher incidence of relapse and poorer prognosis in patients undergoing standard ALL treatment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3324/haematol.2020.250423DOI Listing
July 2020

Synonymous GATA2 mutations result in selective loss of mutated RNA and are common in patients with GATA2 deficiency.

Leukemia 2020 10 18;34(10):2673-2687. Epub 2020 Jun 18.

Division of Pediatric Hematology and Oncology, Department of Pediatrics and Adolescent Medicine, Medical Center, Faculty of Medicine, University of Freiburg, Freiburg, Germany.

Deficiency of the transcription factor GATA2 is a highly penetrant genetic disorder predisposing to myelodysplastic syndromes (MDS) and immunodeficiency. It has been recognized as the most common cause underlying primary MDS in children. Triggered by the discovery of a recurrent synonymous GATA2 variant, we systematically investigated 911 patients with phenotype of pediatric MDS or cellular deficiencies for the presence of synonymous alterations in GATA2. In total, we identified nine individuals with five heterozygous synonymous mutations: c.351C>G, p.T117T (N = 4); c.649C>T, p.L217L; c.981G>A, p.G327G; c.1023C>T, p.A341A; and c.1416G>A, p.P472P (N = 2). They accounted for 8.2% (9/110) of cases with GATA2 deficiency in our cohort and resulted in selective loss of mutant RNA. While for the hotspot mutation (c.351C>G) a splicing error leading to RNA and protein reduction was identified, severe, likely late stage RNA loss without splicing disruption was found for other mutations. Finally, the synonymous mutations did not alter protein function or stability. In summary, synonymous GATA2 substitutions are a new common cause of GATA2 deficiency. These findings have broad implications for genetic counseling and pathogenic variant discovery in Mendelian disorders.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41375-020-0899-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7515837PMC
October 2020

Metabolic profile of leukemia cells influences treatment efficacy of L-asparaginase.

BMC Cancer 2020 Jun 5;20(1):526. Epub 2020 Jun 5.

CLIP - Childhood Leukaemia Investigation Prague, Prague, Czech Republic.

Background: Effectiveness of L-asparaginase administration in acute lymphoblastic leukemia treatment is mirrored in the overall outcome of patients. Generally, leukemia patients differ in their sensitivity to L-asparaginase; however, the mechanism underlying their inter-individual differences is still not fully understood. We have previously shown that L-asparaginase rewires the biosynthetic and bioenergetic pathways of leukemia cells to activate both anti-leukemic and pro-survival processes. Herein, we investigated the relationship between the metabolic profile of leukemia cells and their sensitivity to currently used cytostatic drugs.

Methods: Altogether, 19 leukemia cell lines, primary leukemia cells from 26 patients and 2 healthy controls were used. Glycolytic function and mitochondrial respiration were measured using Seahorse Bioanalyzer. Sensitivity to cytostatics was measured using MTS assay and/or absolute count and flow cytometry. Mitochondrial membrane potential was determined as TMRE fluorescence.

Results: Using cell lines and primary patient samples we characterized the basal metabolic state of cells derived from different leukemia subtypes and assessed their sensitivity to cytostatic drugs. We found that leukemia cells cluster into distinct groups according to their metabolic profile. Lymphoid leukemia cell lines and patients sensitive to L-asparaginase clustered into the low glycolytic cluster. While lymphoid leukemia cells with lower sensitivity to L-asparaginase together with resistant normal mononuclear blood cells gathered into the high glycolytic cluster. Furthermore, we observed a correlation of specific metabolic parameters with the sensitivity to L-asparaginase. Greater ATP-linked respiration and lower basal mitochondrial membrane potential in cells significantly correlated with higher sensitivity to L-asparaginase. No such correlation was found in the other cytostatic drugs tested by us.

Conclusions: These data support that cell metabolism plays a prominent role in the treatment effect of L-asparaginase. Based on these findings, leukemia patients with lower sensitivity to L-asparaginase with no specific genetic characterization could be identified by their metabolic profile.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12885-020-07020-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7275298PMC
June 2020

Flash survey on severe acute respiratory syndrome coronavirus-2 infections in paediatric patients on anticancer treatment.

Eur J Cancer 2020 06 7;132:11-16. Epub 2020 Apr 7.

Childrens Hospital Medical Center Schleswig-Holstein, Kiel, Germany.

Introduction: Since the beginning of COVID-19 pandemic, it is known that the severe course of the disease occurs mostly among the elderly, whereas it is rare among children and young adults. Comorbidities, in particular, diabetes and hypertension, clearly associated with age, besides obesity and smoke, are strongly associated with the need for intensive treatment and a dismal outcome. A weaker immunity of the elderly has been proposed as a possible explanation of this uneven age distribution. Thus, there is concern that children treated for cancer may allso be at risk for an unfavourable course of infection. Along the same line, anecdotal information from Wuhan, China, mentioned a severe course of COVID-19 in a child treated for leukaemia.

Aim And Methods: We made a flash survey on COVID-19 incidence and severity among children on anticancer treatment. Respondents were asked by email to fill in a short Web-based survey.

Results: We received reports from 25 countries, where approximately 10,000 patients at risk are followed up. At the time of the survey, more than 200 of these children were tested, nine of whom were positive for COVID-19. Eight of the nine cases had asymptomatic to mild disease, and one was just diagnosed with COVID-19. We also discuss preventive measures that are in place or should be taken and treatment options in immunocompromised children with COVID-19.

Conclusion: Thus, even children receiving anticancer chemotherapy may have a mild or asymptomatic course of COVID-19. While we should not underestimate the risk of developing a more severe course of COVID-19 than that observed here, the intensity of preventive measures should not cause delays or obstructions in oncological treatment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ejca.2020.03.021DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7141482PMC
June 2020

Chromosome 21 gain is dispensable for transient myeloproliferative disorder driven by a novel GATA1 mutation.

Leukemia 2020 09 24;34(9):2503-2508. Epub 2020 Feb 24.

CLIP-Childhood Leukaemia Investigation Prague, Prague, Czech Republic.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41375-020-0769-1DOI Listing
September 2020

Therapeutic Drug Monitoring of Asparaginase: Intra-individual Variability and Predictivity in Children With Acute Lymphoblastic Leukemia Treated With PEG-Asparaginase in the AIEOP-BFM Acute Lymphoblastic Leukemia 2009 Study.

Ther Drug Monit 2020 06;42(3):435-444

Department of Pediatric Hematology and Oncology, University Children's Hospital of Münster, Münster, Germany.

Background: Therapeutic drug monitoring (TDM) can identify patients with subtherapeutic asparaginase (ASNase) activity [silent inactivation (SI)] and prospectively guide therapeutic adaptation. However, limited intra-individual variability is a precondition for targeted dosing and the diagnosis of SI.

Methods: In the AIEOP-BFM acute lymphoblastic leukemia (ALL) 2009 trial, 2771 children with ALL were included and underwent ASNase-TDM in a central laboratory in Münster. Two biweekly administrations of pegylated ASNase during induction and a third dose during reinduction or the high-risk block, which was administered several weeks later, were monitored. We calculated (1) the incidence of SI; and (2) the predictivity of SI for SI after the subsequent administration. ASNase activities monitored during induction were categorized into percentiles at the respective sampling time points. These percentiles were used to calculate the intra-individual range of percentiles as a surrogate for intrapatient variability and to evaluate the predictivity of ASNase activity for the subsequent administration.

Results: The overall incidence of SI was low (4.9%). The positive predictive value of SI identified by one sample was ≤21%. Confirmation of SI by a second sample indicated a high positive predictive value of 100% for biweekly administrations, but not for administration more than 17 weeks later. Sampling and/or documentation errors were risks for misdiagnosis of SI. High intra-individual variability in ASNase activities, with ranges of percentiles over more than 2 quartiles and low predictivity, was observed in approximately 25% of the patients. These patients were likely to fail dose individualization based on TDM data.

Conclusions: To use TDM as a basis for clinical decisions, standardized clinical procedures are required and high intra-individual variability should be taken into account. Details of the treatment are available in the European Clinical Trials Database at https://www.clinicaltrialsregister.eu/ctr-search/trial/2007-004270-43/DE.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/FTD.0000000000000727DOI Listing
June 2020

Rare IDH1 variants are common in pediatric hemispheric diffuse astrocytomas and frequently associated with Li-Fraumeni syndrome.

Acta Neuropathol 2020 04 3;139(4):795-797. Epub 2020 Jan 3.

Prague Brain Tumor Research Group, Second Faculty of Medicine, Charles University and University Hospital Motol, Prague, Czech Republic.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00401-019-02118-5DOI Listing
April 2020

Novel SAMD9 Mutation in a Patient With Immunodeficiency, Neutropenia, Impaired Anti-CMV Response, and Severe Gastrointestinal Involvement.

Front Immunol 2019 18;10:2194. Epub 2019 Sep 18.

Department of Paediatric Haematology and Oncology, 2nd Faculty of Medicine, Charles University and University Hospital Motol, Prague, Czechia.

Mutations in the Sterile alpha motif domain containing 9 () gene have been described in patients with severe multisystem disorder, MIRAGE syndrome, but also in patients with bone marrow (BM) failure in the absence of other systemic symptoms. The role of hematopoietic stem cell transplantation (HSCT) in the management of the disease is still unclear. Here, we present a patient with a novel mutation in (c.2471 G>A, p.R824Q), manifesting with prominent gastrointestinal tract involvement and immunodeficiency, but without any sign of adrenal insufficiency typical for MIRAGE syndrome. He suffered from severe CMV (cytomegalovirus) infection at 3 months of age, with a delayed development of T lymphocyte functional response against CMV, profound T cell activation, significantly reduced B lymphocyte counts and impaired lymphocyte proliferative response. Cultured T cells displayed slightly lower calcium flux and decreased survival. At the age of 6 months, he developed severe neutropenia requiring G-CSF administration, and despite only mild morphological and immunophenotypical disturbances in the BM, 78% of the BM cells showed monosomy 7 at the age of 18 months. Surprisingly, T cell proliferation after CD3 stimulation and apoptosis of the cells normalized during the follow-up, possibly reflecting the gradual development of monosomy 7. Among other prominent symptoms, he had difficulty swallowing, requiring percutaneous endoscopic gastrostomy (PEG), frequent gastrointestinal infections, and perianal erosions. He suffered from repeated infections and periodic recurring fevers with the elevation of inflammatory markers. At 26 months of age, he underwent HSCT that significantly improved hematological and immunological laboratory parameters. Nevertheless, he continued to suffer from other conditions, and subsequently, he died at day 440 post-transplant due to sepsis. Pathogenicity of this novel mutation was confirmed experimentally. Expression of mutant caused a significant decrease in proliferation and increase in cell death of the transfected cells. We describe a novel mutation in a patient with prominent gastrointestinal and immunological symptoms but without adrenal hypoplasia. Thus, SAMD9 mutations should be considered as cause of enteropathy in pediatric patients. The insufficient therapeutic outcome of transplantation further questions the role of HSCT in the management of patients with mutations and multisystem involvement.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fimmu.2019.02194DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6759462PMC
November 2020

Outcome of Infants Younger Than 1 Year With Acute Lymphoblastic Leukemia Treated With the Interfant-06 Protocol: Results From an International Phase III Randomized Study.

J Clin Oncol 2019 09 8;37(25):2246-2256. Epub 2019 Jul 8.

University of Milano-Bicocca, Monza, Italy.

Purpose: Infant acute lymphoblastic leukemia (ALL) is characterized by () gene rearrangements and coexpression of myeloid markers. The Interfant-06 study, comprising 18 national and international study groups, tested whether myeloid-style consolidation chemotherapy is superior to lymphoid style, the role of stem-cell transplantation (SCT), and which factors had independent prognostic value.

Materials And Methods: Three risk groups were defined: low risk (LR): germline; high risk (HR): -rearranged and older than 6 months with WBC count 300 × 10/L or more or a poor prednisone response; and medium risk (MR): all other -rearranged cases. Patients in the MR and HR groups were randomly assigned to receive the lymphoid course low-dose cytosine arabinoside [araC], 6-mercaptopurine, cyclophosphamide (IB) or experimental myeloid courses, namely araC, daunorubicin, etoposide (ADE) and mitoxantrone, araC, etoposide (MAE).

Results: A total of 651 infants were included, with 6-year event-free survival (EFS) and overall survival of 46.1% (SE, 2.1) and 58.2% (SE, 2.0). In West European/North American groups, 6-year EFS and overall survival were 49.4% (SE, 2.5) and 62.1% (SE, 2.4), which were 10% to 12% higher than in other countries. The 6-year probability of disease-free survival was comparable for the randomized arms (ADE+MAE 39.3% [SE 4.0; n = 169] IB 36.8% [SE, 3.9; n = 161]; log-rank = .47). The 6-year EFS rate of patients in the HR group was 20.9% (SE, 3.4) with the intention to undergo SCT; only 46% of them received SCT, because many had early events. rearrangement was the strongest prognostic factor for EFS, followed by age, WBC count, and prednisone response.

Conclusion: Early intensification with postinduction myeloid-type chemotherapy courses did not significantly improve outcome for infant ALL compared with the lymphoid-type course IB. Outcome for infant ALL in Interfant-06 did not improve compared with that in Interfant-99.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1200/JCO.19.00261DOI Listing
September 2019

Phase I dose-escalation study of volasertib in pediatric patients with acute leukemia or advanced solid tumors.

Pediatr Blood Cancer 2019 10 5;66(10):e27900. Epub 2019 Jul 5.

Department of Paediatrics, University Hospital Essen, Essen, Germany.

Background: Volasertib induces mitotic arrest and apoptosis by targeting Polo-like kinases. In this phase I dose-escalation study, the maximum tolerated dose (MTD), pharmacokinetics (PK), and preliminary efficacy of volasertib were determined in pediatric patients.

Methods: Patients aged 2 to <18 years with relapsed/refractory acute leukemia/advanced solid tumors (ST) without available effective treatments were enrolled-cohort C1 (aged 2 to <12 years); cohort C2 (aged 12 to <18 years). The patients received volasertib intravenously (starting dose: 200 mg/m body surface area on day 1, every 14 days). The primary endpoint was the pediatric MTD for further development.

Results: Twenty-two patients received treatment (C1: leukemia, n = 4; ST, n = 8; C2: leukemia, n = 3; ST, n = 7). No dose-limiting toxicities (DLTs) occurred up to 300 mg/m volasertib in C1; two patients in C2, at 250 mg/m volasertib, had DLTs in cycle 1, one of which led to death; therefore, the MTD of volasertib in C2 was 200 mg/m . The most common grade 3/4 adverse events (all patients) were febrile neutropenia, thrombocytopenia, and neutropenia (41% each). Stable disease (SD) was the best objective response (leukemia, n = 5; ST, n = 2); the duration of SD was short in all patients, except in one with an ST. PK profiles were generally comparable across dose groups and were consistent with those in adults.

Conclusion: The pediatric MTD/dose for further development was identified. There were no unexpected safety or PK findings; limited antitumor/antileukemic activity was demonstrated.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/pbc.27900DOI Listing
October 2019

Cytometric analysis of cell suspension generated by cavitron ultrasonic surgical aspirator in pediatric brain tumors.

J Neurooncol 2019 May 2;143(1):15-25. Epub 2019 Mar 2.

CLIP - Childhood Leukaemia Investigation Prague, Prague, Czech Republic.

Purpose: The aim of this study was to test the possibility of using specimens obtained by a cavitron ultrasonic surgical aspirator (CUSA) in flow and mass cytometry investigations of pediatric brain tumors.

Methods: CUSA specimens obtained from 19 pediatric patients with brain tumors were investigated. Flow and mass cytometry methods were applied to analyze the composition of material collected using the CUSA. Cell suspensions were prepared from CUSA aspirates. Then sample viability was assessed by conventional flow cytometry and subsequently stained with a panel of 31 metal-labeled antibodies.

Results: Viability assessment was performed using conventional flow cytometry. Viability of cells in the acquired samples was below 50% in 16 of 19 cases. A mass cytometry investigation and subsequent analysis enabled us to discriminate brain tumor cells from contaminating leukocytes, whose proportions varied across the specimens. The addition of the viability marker cisplatin directly into the mass cytometry panel gave the means to selecting viable cells only for subsequent analyses. The proportion of non-viable cells was higher among tumor cells compared leukocytes.

Conclusions: When the analysis of the tumor cell immunophenotype is performed with markers for determining viability, the expression of the investigated markers can be evaluated. Suitable markers can be selected by high-throughput methods, such as mass cytometry, and those that are diagnostically relevant can be investigated using flow cytometry, which is more flexible in terms of time.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11060-019-03135-wDOI Listing
May 2019

Increased proportions of γδ T lymphocytes in atypical SCID associate with disease manifestations.

Clin Immunol 2019 04 15;201:30-34. Epub 2019 Feb 15.

Center for Chronic Immunodeficiency, Medical Center, Faculty of Medicine, University of Freiburg, Freiburg, Germany; Center for Pediatrics and Adolescent Medicine, Medical Center, Faculty of Medicine, University of Freiburg, Freiburg, Germany. Electronic address:

Severe combined immunodeficiencies (SCID) comprise a group of genetic diseases characterized by abrogated development of T lymphocytes. In some case reports of atypical SCID patients elevated proportions of γδ T lymphocytes have been reported. However, it is unknown whether these γδ T cells modulate or reflect the patient's clinical phenotype. We investigated the frequency of elevated γδ T cell proportions and associations with clinical disease manifestations in a cohort of 76 atypical SCID patients. Increased proportions of γδ T lymphocytes were present in approximately 60% of these patients. Furthermore, we identified positive correlations between elevated proportions of γδ T cells and the occurrence of CMV infections and autoimmune cytopenias. We discuss that CMV infections might trigger an expansion of γδ T lymphocytes, which could drive the development of autoimmune cytopenias. We advocate that atypical SCID patients should be screened for elevated proportions of γδ T lymphocytes, CMV infection and autoimmune cytopenias.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.clim.2018.11.006DOI Listing
April 2019

Asparagine levels in the cerebrospinal fluid of children with acute lymphoblastic leukemia treated with pegylated-asparaginase in the induction phase of the AIEOP-BFM ALL 2009 study.

Haematologica 2019 09 31;104(9):1812-1821. Epub 2019 Jan 31.

Department of Pediatric Hematology and Oncology, University Childrens' Hospital of Münster, Münster, Germany.

Asparagine levels in cerebrospinal fluid and serum asparaginase activity were monitored in children with acute lymphoblastic leukemia treated with pegylated-asparaginase. The drug was given intravenously at a dose of 2,500 IU/m on days 12 and 26. Serum and cerebrospinal fluid samples obtained on days 33 and 45 were analyzed centrally. Since physiological levels of asparagine in the cerebrospinal fluid of children and adolescents are 4-10 μmol/L, in this study asparagine depletion was considered complete when the concentration of asparagine was ≤0.2 μmol/L, i.e. below the lower limit of quantification of the assay used. Over 24 months 736 patients (AIEOP n=245, BFM n=491) and 903 cerebrospinal fluid samples (n=686 on day 33 and n=217 on day 45) were available for analysis. Data were analyzed separately for the AIEOP and BFM cohorts and yielded superimposable results. Independently of serum asparaginase activity levels, cerebrospinal fluid asparagine levels were significantly reduced during the investigated study phase but only 28% of analyzed samples showed complete asparagine depletion while relevant levels, ≥1 μmol/L, were still detectable in around 23% of them. Complete cerebrospinal fluid asparagine depletion was found in around 5-6% and 33-37% of samples at serum asparaginase activity levels <100 and ≥ 1,500 IU/L, respectively. In this study cerebrospinal fluid asparagine levels were reduced during pegylated-asparaginase treatment, but complete depletion was only observed in a minority of patients. No clear threshold of serum pegylated-asparaginase activity level resulting in complete cerebrospinal fluid asparagine depletion was identified. The consistency of the results found in the two independent data sets strengthen the observations of this study. Details of the treatment are available in the European Clinical Trials Database at .
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3324/haematol.2018.206433DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6717578PMC
September 2019

Outcome of Children With Hypodiploid Acute Lymphoblastic Leukemia: A Retrospective Multinational Study.

J Clin Oncol 2019 04 18;37(10):770-779. Epub 2019 Jan 18.

2 University of Milano-Bicocca, Monza, Italy.

Purpose: We determined the prognostic factors and utility of allogeneic hematopoietic cell transplantation among children with newly diagnosed hypodiploid acute lymphoblastic leukemia (ALL) treated in contemporary clinical trials.

Patients And Methods: This retrospective study collected data on 306 patients with hypodiploid ALL who were enrolled in the protocols of 16 cooperative study groups or institutions between 1997 and 2013. The clinical and biologic characteristics, early therapeutic responses as determined by minimal residual disease (MRD) assessment, treatment with or without MRD-stratified protocols, and allogeneic transplantation were analyzed for their impact on outcome.

Results: With a median follow-up of 6.6 years, the 5-year event-free survival rate was 55.1% (95% CI, 49.3% to 61.5%), and the 5-year overall survival rate was 61.2% (95% CI, 55.5% to 67.4%) for the 272 evaluable patients. Negative MRD at the end of remission induction, high hypodiploidy with 44 chromosomes, and treatment in MRD-stratified protocols were associated with a favorable prognosis, with a 5-year event-free survival rate of 75% (95% CI, 66.0% to 85.0%), 74% (95% CI, 61.0% to 89.0%), and 62% (95% CI, 55.0% to 69.0%), respectively. After exclusion of patients with high hypodiploidy with 44 chromosomes and adjustment for waiting time to transplantation and for covariables in a Poisson model, disease-free survival did not differ significantly ( P = .16) between the 42 patients who underwent transplantation and the 186 patients who received chemotherapy only, with an estimated 5-year survival rate of 59% (95% CI, 46.5% to 75.0%) versus 51.5% (95% CI, 44.7% to 59.4%), respectively. Transplantation produced no significant impact on outcome compared with chemotherapy alone, especially among the subgroup of patients who achieved a negative MRD status upon completion of remission induction.

Conclusion: MRD-stratified treatments improved the outcome for children with hypodiploid ALL. Allogeneic transplantation did not significantly improve outcome overall and, in particular, for patients who achieved MRD-negative status after induction.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1200/JCO.18.00822DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7051863PMC
April 2019

Validation of the United Kingdom copy-number alteration classifier in 3239 children with B-cell precursor ALL.

Blood Adv 2019 01;3(2):148-157

Wolfson Childhood Cancer Research Centre, Northern Institute for Cancer Research, Newcastle University, Newcastle, United Kingdom.

Genetic abnormalities provide vital diagnostic and prognostic information in pediatric acute lymphoblastic leukemia (ALL) and are increasingly used to assign patients to risk groups. We recently proposed a novel classifier based on the copy-number alteration (CNA) profile of the 8 most commonly deleted genes in B-cell precursor ALL. This classifier defined 3 CNA subgroups in consecutive UK trials and was able to discriminate patients with intermediate-risk cytogenetics. In this study, we sought to validate the United Kingdom ALL (UKALL)-CNA classifier and reevaluate the interaction with cytogenetic risk groups using individual patient data from 3239 cases collected from 12 groups within the International BFM Study Group. The classifier was validated and defined 3 risk groups with distinct event-free survival (EFS) rates: good (88%), intermediate (76%), and poor (68%) ( < .001). There was no evidence of heterogeneity, even within trials that used minimal residual disease to guide therapy. By integrating CNA and cytogenetic data, we replicated our original key observation that patients with intermediate-risk cytogenetics can be stratified into 2 prognostic subgroups. Group A had an EFS rate of 86% (similar to patients with good-risk cytogenetics), while group B patients had a significantly inferior rate (73%, < .001). Finally, we revised the overall genetic classification by defining 4 risk groups with distinct EFS rates: very good (91%), good (81%), intermediate (73%), and poor (54%), < .001. In conclusion, the UKALL-CNA classifier is a robust prognostic tool that can be deployed in different trial settings and used to refine established cytogenetic risk groups.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1182/bloodadvances.2018025718DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6341196PMC
January 2019

Genomic landscape of pediatric B-other acute lymphoblastic leukemia in a consecutive European cohort.

Haematologica 2019 07 10;104(7):1396-1406. Epub 2019 Jan 10.

CLIP - Childhood Leukaemia Investigation Prague

Novel biological subtypes and clinically important genetic aberrations (druggable lesions, prognostic factors) have been described in B-other acute lymphoblastic leukemia (ALL) during the last decade; however, due to a lack of studies on unselected cohorts, their population frequency and mutual associations still have to be established. We studied 110 consecutively diagnosed and uniformly treated childhood B-other patients using single nucleotide polymorphism arrays and whole exome/transcriptome sequencing. The frequency of -rearranged, -like, -rearranged, -like, iAMP21 and -rearranged subtypes was 27%, 15%, 5%, 5%, 4%, and 2%, respectively; 43% of cases were not classified into any of these subtypes (B-rest). We found worse early response to treatment in -rearranged leukemia and a strong association of -rearranged leukemia with B-myeloid immunophenotype. Of the druggable lesions, JAK/STAT-class and RAS/RAF/MAPK-class aberrations were found in 21% and 43% of patients, respectively; an ABL-class aberration was found in one patient. A recently described negative prognostic factor, , was found in 14% of patients and was enriched in (but not exclusive for) -like subtype. fusions (including 4 novel), intragenic amplifications and P80R mutations were mutually exclusive and only occurred in the B-rest subset, altogether accounting for 20% of the B-other group. P80R was associated with a specific gene expression signature, potentially defining a novel leukemia subtype. Our study shows unbiased European population-based frequencies of novel ALL subtypes, recurrent (cyto)genetic aberrations and their mutual associations. This study also strengthens and widens the current knowledge of B-other ALL and provides an objective basis for optimization of current genetic diagnostics.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3324/haematol.2018.204974DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6601078PMC
July 2019

deletions in childhood acute lymphoblastic leukemia with rearrangements are mostly polyclonal, prognostically relevant and their detection rate strongly depends on screening method sensitivity.

Haematologica 2019 07 10;104(7):1407-1416. Epub 2019 Jan 10.

CLIP - Childhood Leukaemia Investigation Prague.

-deletions occur recurrently in acute lymphoblastic leukemia, especially in the -rearranged subtype. The -deletion was shown to positively impact prognosis of patients with -deletion and its presence precludes assignment into group, a novel high-risk category on AIEOP-BFM ALL trials. We analyzed the impact of different methods on -deletion detection rate, evaluated -deletion as a potential marker for -rearranged leukemia, studied its associations with molecular and clinical characteristics within this leukemia subtype, and analyzed its clonality. Using single-nucleotide-polymorphism array, genomic polymerase chain reaction (PCR) and amplicon-sequencing we found -deletion in 34% (16 of 47), 66% (33 of 50) and 78% (39 of 50) of -rearranged leukemia, respectively. False negativity of -deletion by single-nucleotide-polymorphism array caused misclassification in 5 patients. No -deletion was found outside the -rearranged cases. Within -rearranged leukemia, the -deletion was associated with higher total number of copy-number aberrations, and, importantly, the -deletion positivity by PCR was associated with better outcome [5-year event-free survival (EFS), -deletion-positive 93% -deletion-negative 68%, =0.022; 5-year overall survival (OS), -deletion-positive 97% -deletion-negative 75%, =0.029]. Ultra-deep amplicon-sequencing revealed distinct co-existing -deletions in 22 of 24 patients. In conclusion, our data demonstrate inadequate sensitivity of single-nucleotide-polymorphism array for -deletion detection, unacceptable for proper classification. Even using more sensitive methods (PCR/amplicon-sequencing) for its detection, -deletion is absent in 22-34% of -rearranged leukemia and does not represent an adequately sensitive marker of this leukemia subtype. Importantly, the -deletion potentially stratifies the -rearranged leukemia into biologically/clinically distinct subsets. Frequent polyclonal pattern of -deletions shows that late origin of this lesion is more common than has been previously described.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3324/haematol.2018.204487DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6601096PMC
July 2019

Sideroblastic anemia associated with multisystem mitochondrial disorders.

Pediatr Blood Cancer 2019 04 26;66(4):e27591. Epub 2018 Dec 26.

Department of Paediatrics and Adolescent Medicine, First Faculty of Medicine, Charles University and General University Hospital, Prague, Czech Republic.

Background: Sideroblastic anemia represents a heterogeneous group of inherited or acquired diseases with disrupted erythroblast iron utilization, ineffective erythropoiesis, and variable systemic iron overload. In a cohort of 421 patients with multisystem mitochondrial diseases, refractory anemia was found in 8 children.

Results: Five children had sideroblastic anemia with increased numbers of ring sideroblasts >15%. Two of the children had a fatal course of MLASA1 syndrome (mitochondrial myopathy, lactic acidosis, and sideroblastic anemia [SA]) due to a homozygous, 6-kb deletion in the PUS1 gene, part of the six-member family of pseudouridine synthases (pseudouridylases). Large homozygous deletions represent a novel cause of presumed PUS1-loss-of-function phenotype. The other three children with SA had Pearson syndrome (PS) due to mtDNA deletions of 4 to 8 kb; two of these children showed early onset of PS and died due to repeated sepsis; the other child had later onset of PS and survived as the hematological parameters normalized and the disease transitioned to Kearns-Sayre syndrome. In addition, anemia without ring sideroblasts was found in three other patients with mitochondrial disorders, including two children with later onset of PS and one child with failure to thrive, microcephaly, developmental delay, hypertrophic cardiomyopathy, and renal tubular acidosis due to the heterozygous mutations c.610A>G (p.Asn204Asp) and c.674C>T (p.Pro225Leu) in the COX10 gene encoding the cytochrome c oxidase assembly factor.

Conclusions: Sideroblastic anemia was found in fewer than 1.2% of patients with multisystem mitochondrial disease, and it was usually associated with an unfavorable prognosis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/pbc.27591DOI Listing
April 2019