Project description:Acute lymphoblastic leukemia (ALL) is the most common pediatric, and ninth most common adult, cancer. ALL can develop in either B or T lymphocytes, but B-lineage ALL (B-ALL) exceeds T-ALL clinically. As for other cancers, animal models allow study of the molecular mechanisms driving ALL. Several zebrafish (Danio rerio) T-ALL models have been reported, but until recently, robust D. rerio B-ALL models were not described. Then, D. rerio B-ALL was discovered in two related zebrafish transgenic lines; both were already known to develop T-ALL. Here, we report new B-ALL findings in one of these models, fish expressing transgenic human MYC (hMYC). We describe B-ALL incidence in a large cohort of hMYC fish, and show B-ALL in two new lines where T-ALL does not interfere with B-ALL detection. We also demonstrate B-ALL responses to steroid and radiation treatments, which effect ALL remissions, but are usually followed by prompt relapses. Finally, we report gene expression in zebrafish B lymphocytes and B-ALL, in both bulk samples and single B- and T-ALL cells. Using these gene expression profiles, we compare differences between the two new D. rerio B-ALL models, which are both driven by transgenic mammalian MYC oncoproteins. Collectively, these new data expand the utility of this new vertebrate B-ALL model.
Project description:Childhood acute lymphoblastic leukemia (ALL) has an origin in the fetal period which may distinguish it from ALL diagnosed later in life. We wanted to test whether familial risks differ in ALL diagnosed in the very early childhood from ALL diagnosed later. The Swedish nation-wide family-cancer data were used until year 2016 to calculate standardized incidence ratios (SIRs) for familial risks in ALL in three diagnostic age-groups: 0-4, 5-34 and 35 + years. Among 1335 ALL patients diagnosed before age 5, familial risks were increased for esophageal (4.78), breast (1.42), prostate (1.40) and connective tissue (2.97) cancers and leukemia (2.51, ALL 7.81). In age-group 5-34 years, rectal (1.73) and endometrial (2.40) cancer, myeloma (2.25) and leukemia (2.00, ALL 4.60) reached statistical significance. In the oldest age-group, the only association was with Hodgkin lymphoma (3.42). Diagnostic ages of family members of ALL patients were significantly lower compared to these cancers in the population for breast, prostate and rectal cancers. The patterns of increased familial cancers suggest that BRCA2 mutations could contribute to associations of ALL with breast and prostate cancers, and mismatch gene PMS2 mutations with rectal and endometrial cancers. Future DNA sequencing data will be a test for these familial predictions.
Project description:Coronavirus disease 2019 (COVID-19) is generally milder in children than in adults, and a substantial proportion of children with the disease have asymptomatic infections. Remdesivir is recommended for severe COVID-19. To date, there are little data on the outcomes of remdesivir treatment in children. We report a case of severe COVID-19 in a previously healthy but obese (body mass index, 27.6; 99.8th percentile of the age) 9-year-old boy treated with remdesivir and dexamethasone. The patient had pneumonia at the time of diagnosis and required supplemental oxygen due to hypoxia one day after diagnosis. The patient developed respiratory distress as his pneumonia progressed rapidly. Therefore, remdesivir with dexamethasone therapy was initiated on hospital day 2. Supplemental oxygen was gradually weaned on hospital day 6 and stopped on hospital day 9. Significant improvement in pneumonic consolidations on chest X-ray was noted on hospital day 8. The patient was discharged on hospital day 21. We did not observe any adverse effects of remdesivir therapy and successfully treated a 9-year-old child with severe COVID-19.
Project description:Myocardial infiltration by eosinophils leads to myocardial inflammation and fibrosis, resulting in restrictive hemodynamics. We describe an uncommon presentation of eosinophilic predominant acute lymphoblastic leukemia that manifested with hypereosinophilic infiltrative myocarditis. (Level of Difficulty: Advanced.).
Project description:We report a case of Trichosporon loubieri (T. loubieri) fungemia with likely liver involvement in a 39-year-old Caucasian patient with relapsed B-cell acute lymphoblastic leukemia after an allogeneic hematopoietic cell transplant. This is the fifth published case of T. loubieri infection and only the third case of T. loubieri fungemia, to our knowledge. All 3 cases of T. loubieri infection with fungemia had liver involvement.
Project description:DNA methylation appears to play an essential mechanistic role in the pathogenesis of ALL, thereby potentiate its use as a biomarker for diagnosis and prognosis (Milani, Lundmark et al. 2010; Geng, Brennan et al. 2012; Sandoval, Heyn et al. 2013), and even a potential target of novel therapeutic approaches in ALL. In present study, we collected blood specimens for 4 pairs of monozygotic twins (MZ) and 1 pair of dizygotic twin (DZ) that are discordant for ALL. We sought to comprehensively assess the magnitude of genetic and epigenetic differences between ALL-affected and unaffected twins. we conducted whole genome and whole methylome sequencing on these five pairs of ALL-discordant twins. We also examined both the MZ and DZ twins using whole-genome bisulfite sequencing (WGBS). At first, the methylation differences across the genome were addressed globally by Circos software. And then tried to characterize the co-twin methylation divergence in specific genomic regions between ALL-discordant twin pairs. These patterns of dynamic co-twin methylation changes in these discordant ALL samples were generally consistent among MZ and DZ twins, indicating similarities of methylation abnormalities. As a result, 780, 566, 309, 293 and 2110 DMRs were identified, with a similar distribution pattern across different genomic elements among the five twin pairs.Then we annotate whether these DMRs were located in regulatory elements and identification of genes with recurring methylation alterations in a cohort of ALL patients. We collected blood specimens from 4 pairs of MZ twins and 1 pair of DZ twin that are discordant for ALL. At first, the methylation differences across the genome were addressed globally by Circos software. And then tried to characterize the co-twin methylation divergence in specific genomic regions and differentially methylated gene regions (DMRs) were identified between ALL-discordant twin pairs. Then we annotate whether these DMRs were located in regulatory elements and identification of genes with recurring methylation alterations in a cohort of ALL patients.
Project description:The pharmacokinetics, pharmacodynamics, efficacy and safety of a new recombinant E. coli-asparaginase preparation were evaluated in infants (<1 year of age) with de novo acute lymphoblastic leukemia. Twelve patients were treated according to the INTERFANT-06 protocol and received up to 10,000 U/m(2) recombinant asparaginase as intravenous infusions on days 15, 18, 22, 25, 29 and 33 of remission induction treatment. The asparaginase dose was individually adjusted by protocol to 67% of the calculated dose for infants <6 months, and to 75% of the calculated dose for infants aged 6-12 months. The trough serum asparaginase activities observed were above 20, 50, and 100 U/L in 86%, 71%, and 51% of measured samples, respectively. Looking only at the data assessed 3 days after asparaginase infusion these percentages were 91%, 84%, and 74%, respectively. Asparagine was completely depleted in serum in all but one patient who was the youngest in the study. No anti-asparaginase antibodies were detected during this treatment phase. Observed adverse reactions are known to be possible and are labeled side effects of asparaginase treatment and chemotherapy. We conclude that the asparaginase dose regimen used in infants is safe and provides complete asparagine depletion for the desired time period in nearly all patients. Measured asparaginase trough serum levels justify the higher doses used in infants compared to in older children and show that 3-day intervals are preferred over 4-day intervals. (This trial was registered at www.clinicaltrialsregister.eu as EudraCT number 2008-006300-27).
Project description:Purpose:Mercaptopurine (MP) is one of the main chemotherapeutics for acute lymphoblastic leukemia (ALL). To improve treatment outcomes, constant MP dose titration is essential to maintain steady drug exposure, while minimizing myelosuppression. We performed two-stage analyses to identify genetic determinants of MP-related neutropenia in Korean pediatric ALL patients. Materials and Methods:Targeted sequencing of 40 patients who exhibited definite MP intolerance was conducted using a novel panel of 211 pharmacogenetic-related genes, and subsequent analysis was performed with 185 patients. Results:Using bioinformatics tools and genetic data, four functionally interesting variants were selected (ABCC4, APEX1, CYP1A1, and CYP4F2). Including four variants, 23 variants in 12 genes potentially linked to MP adverse reactions were selected as final candidates for subsequent analysis in 185 patients. Ultimately, a variant allele in APEX1 rs2307486was found to be strongly associated with MP-induced neutropenia that occurred within 28 days of initiating MP (odds ratio, 3.44; p=0.02). Moreover, the cumulative incidence of MP-related neutropenia was significantly higher in patients with APEX1 rs2307486 variants, as GG genotypes were associated with the highest cumulative incidence (p < 0.01). NUDT15 rs116855232 variants were strongly associated with a higher cumulative incidence of neutropenia (p < 0.01), and a lower median dose of tolerated MP throughout maintenance treatment (p < 0.01). Conclusion:We have identified that APEX1 rs2307486 variants conferred an increased risk of MP-related early onset neutropenia. APEX1 and NUDT15 both contribute to cell protection from DNA damage or misincorporation, so alleles that impair the function of either gene may affect MP sensitivities, thereby inducing MP-related neutropenia.
Project description:Childhood acute lymphoblastic leukemia (ALL) peaks around age 2-4, and in utero genetic epigenetic mother-fetus crosstalk might tune ALL onset during childhood life. Folate genes variably interact with vitamin status on ALL risk and prognosis. We investigated DHFR and MTHFR gene variants in 235 ALL children and their mothers to disclose their role in determining ALL onset age and survival. Pyrosequence of DHFR 19bp ins/del (rs70991108; W/D), MTHFR C677T (rs1801133; C>T), and MTHFR A1298C (rs1801131; A>C) was assessed in children and in 72% of mothers for dyad-analysis comparison. DHFR DD-children had delayed ALL onset compared to WW-children (7.5 ± 4.8 vs. 5.2 ± 3.7 years; P = 0.002) as well as MTHFR 1298 CC-children compared to AA-children (8.03 ± 4.8 vs. 5.78 ± 4.1 years; P = 0.006), and according to the strong linkage disequilibrium between MTHFR 677 T-allele and 1298C-allele, MTHFR TT-children showed early mean age of onset though not significant. Offspring of MTHFR 677 TT-mothers had earlier ALL onset compared to offspring of 677 CC-mothers (5.4 ± 3.3 vs. 7 ± 5.3 years; P = 0.017). DHFR/MTHFR 677 polymorphism combination influenced onset age by comparing DD/CC vs. WW/TT children (8.1 ± 5.7 vs. 4.7 ± 2.1 years; P = 0.017). Moreover, mother-child genotype combination gave 5.5-years delayed onset age in favor of DD-offspring of 677 CC-mothers vs. WW-offspring of 677 TT-mothers, and it was further confirmed including any D-carrier children and any 677 T-carrier mothers (P = 0.00052). Correction for multiple comparisons maintained statistical significance for DHFR ins/del and MTHFR A1298C polymorphisms. Unexpectedly, among the very-early onset group (<2.89 years; 25th), DD-genotype inversely clustered in children and mothers (4.8% vs. 23.8% respectively), and accordingly ALL offspring of homozygous DD-mothers had increased risk to have early-onset (adjusted OR (odds ratio) = 3.08; 1.1-8.6; P = 0.03). The opposite effect DHFR promoter variant has in tuning ALL onset-time depending on who is the carrier (i.e., mother or child) might suggest a parent-origin-effect of the D-allele or a two-faced epigenetic role driven by unbalanced folate isoform availability during the in-utero leukemogenesis responsible for the wide postnatal childhood ALL latency.