Despite therapeutic advances, high-risk neuroblastoma is still associated with a poor long-term prognosis. Immunotherapy with the anti-GD2 antibody dinutuximab beta has recently been added to the ...standard of care for patients with high-risk neuroblastoma in our center in Bratislava, and our initial experience with dinutuximab beta has been reported previously. Here we provide a follow-up on the outcomes of 7 patients who were treated with dinutuximab beta under clinical practice conditions at our center.Medical records of 31 patients diagnosed with neuroblastoma between 2017 and 2020 at the Children's Hematology and Oncology Clinic in Bratislava were retrospectively reviewed and 7 patients with high-risk neuroblastoma who were treated with dinutuximab beta were identified. All 7 patients received dinutuximab beta as continuous infusion over 10 days at a dose of 10 mg/m2/day for 5 cycles, following induction and consolidation therapy. Supportive therapy was administered to manage adverse events. Clinical outcomes and treatment tolerance were evaluated.Six of 7 patients treated with dinutuximab beta achieved complete remission, with a median duration of response of 21.5 months as of January 2022, and 1 displayed stable disease 21 months after treatment completion. Treatment was tolerable in most patients, with the majority of adverse events managed with supportive care.Dinutuximab beta is an effective immunotherapy for patients with high-risk neuroblastoma in routine clinical practice when coupled with optimal supportive management of adverse events.
The gut microbiota of paediatric oncology patients undergoing a conditioning regimen before hematopoietic stem cell transplantation is recently considered to play role in febrile neutropenia. ...Disruption of commensal microbiota and evolution of opportune pathogens community carrying a plethora of antibiotic-resistance genes play crucial role. However, the impact, predictive role and association of patient´s gut resistome in the course of the therapy is still to be elucidated. We analysed gut microbiota composition and resistome of 18 paediatric oncology patients undergoing hematopoietic stem cell transplantation, including 12 patients developing febrile neutropenia, hospitalized at The Bone Marrow Transplantation Unit of the National Institute of Children´s disease in Slovak Republic and healthy individuals (n = 14). Gut microbiome of stool samples obtained in 3 time points, before hematopoietic stem cell transplantation (n = 16), one week after hematopoietic stem cell transplantation (n = 16) and four weeks after hematopoietic stem cell transplantation (n = 14) was investigated using shotgun metagenome sequencing and bioinformatical analysis. We identified significant decrease in alpha-diversity and nine antibiotic-resistance genes msr(C), dfrG, erm(T), VanHAX, erm(B), aac(6)-aph(2), aph(3)-III, ant(6)-Ia and aac(6)-Ii, one week after hematopoietic stem cell transplantation associated with febrile neutropenia. Multidrug-resistant opportune pathogens of ESKAPE, Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae and Escherichia coli found in the gut carried the significant subset of patient's resistome. Over 50% of patients treated with trimethoprim/sulfamethoxazole, piperacillin/tazobactam and amikacin carried antibiotic-resistance genes to applied treatment. The alpha diversity and the resistome of gut microbiota one week after hematopoietic stem cell transplantation is relevant predictor of febrile neutropenia outcome after hematopoietic stem cell transplantation. Furthermore, the interindividual diversity of multi-drug resistant opportunistic pathogens with variable portfolios of antibiotic-resistance genes indicates necessity of preventive, personalized approach.
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.
Langerhans cell histiocytosis (LCH) is a histiocytic disorder driven by a constitutive activation of the MAPK signaling pathway in myeloid cells. In 50-60% of cases, it is caused by the BRAFV600E ...mutation. There is evidence that levels of BRAFV600E in the peripheral blood of patients with LCH correlate with disease burden and could be used as marker for disease extent and response to therapy. However, there is currently no consensus on how testing for minimal disseminated disease should be performed.
Different approaches to determine the mutation load in patients with LCH were assessed and longitudinal evaluation of patient DNA during treatment with chemotherapy and/or the RAF inhibitor vemurafenib was performed. DNA was isolated from whole blood, different leukocyte subsets, and circulating cell-free DNA (ccf-DNA).
We show that determining BRAF levels from whole blood is superior to using ccfDNA. Furthermore, it is important to identify the clinically relevant BRAF-mutated cellular subpopulations such as CD14
monocytes or CD1c
DCs, since other blood cells can also harbor the mutation and therefore confound whole blood or ccfDNA measurements.
Our data support the view that single-agent treatment with an RAF inhibitor reduces disease activity but does not cure LCH.
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.
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.
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.
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.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Children with Down syndrome (DS) up to the age of 4 years are at a 150-fold excess risk of developing myeloid leukemia (ML-DS). Approximately 4%-5% of newborns with DS develop transient ...myeloproliferative disorder (TMD). Blast cell structure and immunophenotype are similar in TMD and ML-DS. A mutation in the hematopoietic transcription factor GATA1 is present in almost all cases. Here, we show that simple techniques detect GATA1 mutations in the largest series of TMD (n = 134; 88%) and ML-DS (n = 103; 85%) cases tested. Furthermore, no significant difference in the mutational spectrum between the 2 disorders was seen. Thus, the type of GATA1 sequence mutation is not a reliable tool and is not prognostic of which patients with TMD are probable to develop ML-DS.
Graft-versus-host disease (GvHD) is a severe complication after hematopoietic stem cell transplantation (HSCT). Our study focused on identifying multidrug-resistant (MDR) gut bacteria associated with ...GvHD-prone guts and association with gut microbiota (GM) diversity, bacteriome, and mycobiome composition in post-HSCT patients. We examined 11 pediatric patients with acute lymphoblastic leukemia (ALL), including six with GvHD, within three time points: seven days pre-HSCT, seven days post-, and 28 days post-HSCT. The gut microbiome and its resistome were investigated using metagenomic sequencing, taxonomically classified with Kraken2, and statistically evaluated for significance using appropriate tests. We observed an increase in the abundance of MDR bacteria, mainly
strains carrying
,
,
,
, and
genes, in GvHD patients one week post-HSCT. Conversely, non-GvHD patients had more MDR beneficial bacteria pre-HSCT, promoting immunosurveillance, with resistance genes increasing one-month post-HSCT. MDR beneficial bacteria included the anti-inflammatory
,
, and
, while most MDR bacteria represented the dominant species of GM. Changes in the gut mycobiome were not associated with MDR bacterial monodominance or GvHD. Significant α-diversity decline (Shannon index) one week and one month post-HSCT in GvHD patients (
< 0.05) was accompanied by increased
and decreased
post-HSCT. Our findings suggest that MDR commensal gut bacteria may preserve diversity and enhance immunosurveillance, potentially preventing GvHD in pediatric ALL patients undergoing HSCT. This observation has therapeutic implications.