PKLR mutations in pyruvate kinase deficient Polish patients: Functional characteristics of c.101-1G > A and c.1058delAAG variants.

Pyruvate kinase (PK) deficiency is a rare autosomal recessive disorder characterized by chronic hemolytic anemia of variable severity. Nine Polish patients with severe hemolytic anemia but normal PK activity were found to carry mutations in the PKLR gene encoding PK, five already known ones and one novel (c.178C > T). We characterized two of the known variants by molecular modeling (c.1058delAAG) and minigene splicing analysis (c.101-1G > A). The former gives a partially destabilized PK tetramer, likely of suboptimal activity, and the c.101-1G > A variant gives alternatively spliced mRNA carrying a premature stop codon, encoding a severely truncated PK and likely undergoing nonsense-mediated decay.

Genetic Profiling in Children With Acute Lymphoblastic Leukemia Referred for Allogeneic Hematopoietic Stem Cell Transplantation.

INTRODUCTION: Hematopoietic stem cell transplantation (HSCT) is the essential and often the only curative therapeutic option in high risk and relapsed pediatric acute lymphoblastic leukemia (ALL). METHODS: The objective of the study was to investigate whole-genome expression in children with high risk or relapsed ALL referred for HSCT. Gene expression was assessed in 18 children with ALL referred for HSCT (10 high risk, 8 relapsed; median age of 9.4 years) and in a control group of 38 obese children (median age of 14.1 years). Whole-genome expression was assessed in leukocytes using GeneChip® HumanGene 1.0 ST microarray. RESULTS: The analysis of genomic profiles revealed a significantly lower expression of 21 genes with a defined function, involved in immunoglobulin production, lymphocyte function, or regulation of DNA processing in ALL patients referred for HSCT compared with the control group. CONCLUSION: Genome expression of patients with ALL in remission referred to HSCT revealed deep immunosuppression of both B-cell and T-cell lineages, which may increase the probability of donor cell engraftment.

Clinical utility of complex assessment with evoked potentials in acute lymphoblastic leukemia survivors: comparison of various treatment protocols.

BACKGROUND: One of the greatest success of pediatric hematology is a prominent improvement of survival in acute lymphoblastic leukemia (ALL). Therefore, special attention needs to be paid to long-term side effects of the treatment such as neurotoxicity. One of the few diagnostic methods that allow an objective assessment of sensory systems are evoked potentials (EP). METHODS: The analyzed group consisted of 167 ALL long-term survivors, aged 4.9-28.4 years, without auditory, visual and sensory deviations. Patients were treated with New York (NY, n = 35), previous modified Berlin-Frankfurt-Münster (pBFM, n = 47) and BFM95 (n = 85) protocols. In order to assess the impact of radiotherapy on recorded EP, a joint analysis of NY and pBFM groups was performed. The control group consisted of 35 patients, aged 6-17 years. The analyzed patients underwent a complex assessment with visual EP (VEP), somatosensory EP (SEP) and brainstem auditory EP (BAEP) in accordance with current standards. RESULTS: ALL treatment contributed to the shortening of wave I latency (1.59 vs 1.90, P = 0.003) and prolongation of I-III (2.23 vs 2.04, P = 0.004) and I-V (4.57 vs 4.24, P = 0.002) interwave latencies of BAEP. A significant effect was also noticed in P100 (106.32 vs 101.57, P < 0.001) and N135 (151.42 vs 138.22, P < 0.001) latencies of VEP and N18 amplitude (3.24 vs 4.70, P = 0.007) and P25 latency (21.32 vs 23.39, P < 0.001) of SEP. The distribution of abnormalities between protocols was similar in BAEP (NY - 68.6%, pBFM - 61.7%, BFM95-69.4%, P = 0.650), VEP (NY - 68.6%, pBFM - 42.5%, BFM95-58.3%, P = 0.053) and significantly different for SEP (NY - 62.9%, pBFM - 36.2%, BFM95-53.0%, P = 0.045). The harmful effect of radiotherapy was most clearly marked in numerous disturbances of SEP parameters. CONCLUSIONS: The presented analysis indicates a high frequency of subclinical abnormalities in EP regardless of the analyzed protocol. To our knowledge current study is the largest and one of the most complex research examining the role of EP in ALL patients. The obtained results indicate the possibility of using a single, objective and non-invasive measurement of EP in ALL survivors in order to stratify the risk of developing sensory abnormalities in adulthood.

Gastrointestinal peptides in children before and after hematopoietic stem cell transplantation.

BACKGROUND: Gastrointestinal tract function and it's integrity are controlled by a number of peptides whose secretion is influenced by severe inflammation. In stomach the main regulatory peptide is ghrelin. For upper small intestine cholecystokinin and lower small intestine glucagon-like peptide- 1 are secreted, while fibroblast growth factor-21 is secreted by several organs, including the liver, pancreas, and adipose tissue [12]. Hematopoietic stem cell transplantation causes serious mucosal damage, which can reflect on this peptides. METHODS: The aim of the study was to determine fasting plasma concentrations of ghrelin, cholecystokinin, glucagon- like peptide-1, and fibroblast growth factor-21, and their gene expressions, before and 6 months after hematopoietic stem cell transplantation.27 children were studied, control group included 26 healthy children. RESULTS: Acute graft versus host disease was diagnosed in 11 patients (41%, n = 27). Median pre-transplantation concentrations of gastrointestinal peptides, as well as their gene expressions, were significantly lower in studied group compared with the control group. Only median of fibroblast growth factor-21 concentration was near-significantly higher before stem cell transplantation than in the control group. The post-hematopoietic transplant results revealed significantly higher concentrations of the studied peptides (except fibroblast growth factor-21) and respective gene expressions as compare to pre transplant results. Median glucagone like peptide-1 concentrations were significantly decreased in patients with features of acute graft versus host disease. Moreover, negative correlation between glucagone like peptide-1 concentrations and acute graft versus host disease severity was found. CONCLUSIONS: Increased concentrations and gene expressions of gastrointestinal tract regulation peptides can be caused by stimulation of regeneration in the severe injured organ. Measurement of these parameters may be a useful method of assessment of severity of gastrointestinal tract complications of hematopoietic stem cell transplantation.

Outcome of acute lymphoblastic leukemia in children with down syndrome-Polish pediatric leukemia and lymphoma study group report.

Children with Down syndrome (DS) have a 20-fold increased risk of developing leukemia compared with the general population. The aim of the study was to analyze the outcome of patients diagnosed with Down syndrome and acute lymphoblastic leukemia (ALL) in Poland between the years 2003 and 2010. A total of 1848 children were diagnosed with ALL (810 females and 1038 males). Of those, 41 (2.2%) had DS. The children were classified into three risk groups: a standard-risk group-14 patients, an intermediate-risk group-24, a high-risk group-3. All patients were treated according to ALLIC 2002 protocol. The median observation time of all patients was 6.1 years, and in patients with DS 5.3 years. Five-year overall survival (OS) was the same in all patients (86% vs 86%, long-rank test, p = .9). The relapse-free survival (RFS) was calculated as 73% in patients with DS and 81% in patients without DS during a median observation time (long-rank test, p = .3). No statistically significant differences were found in the incidence of nonrelapse mortality between those two groups of patients (p = .72). The study was based on children with ALL and Down syndrome who were treated with an identical therapy schedule as ALL patients without DS, according to risk group. This fact can increase the value of the presented results.

Screening of subclinical P300 event-related potentials changes in childhood acute lymphoblastic leukemia survivors.

Modern treatment of childhood acute lymphoblastic leukemia (ALL) has resulted in a high cure rate; however, it can cause central nervous system toxicity. In the present study, a group of 136 ALL survivors were screened for changes in P300. Therapy was conducted according to a modified New York (NY) protocol (30 patients) and two subsequent revisions of a modified Berlin-Frankfurt-Münster (BFM) protocol (32 and 74 patients). The control group consisted of 58 patients. The survivors had significantly prolonged mean latency of P300 (331.31±28.71 vs. 298.14±38.76 msec, P<0.001) and reaction time (439.51±119.86 vs. 380.11±79.94 msec, P=0.002) compared with in the control group. Abnormalities in the endogenous evoked potentials were observed in 36 patients (26.5%). The mean latency time was significantly longer in the treatment groups compared with in the control group (NY: 329.13±28.07 msec, P=0.001; pBFM: 332.97±23.97 msec, P<0.001; BFM95: 331.47±31.05 msec, P<0.001). The reaction time was equally prolonged in both groups. In comparisons between the studied groups and the control group the most significant prolongation was recorded in the NY group (461.8±140.3 vs. 380.1±78.04 msec, P=0.039). Significantly higher frequency of prolonged reaction time in non-irradiated patients that received BFM95 was also revealed (21.62 vs. 15.85%, P=0.007). In addition, radiotherapy significantly reduced the P300 wave amplitude (mean values: 10.395±5.727 vs. 12.739±6.508 mV, P=0.027). In conclusion, endogenous P300 event-related potentials may be a useful tool in screening of subclinical cognitive changes in ALL survivors.

Analysis of Peripheral Blood Mononuclear Cells Gene Expression Highlights the Role of Extracellular Vesicles in the Immune Response following Hematopoietic Stem Cell Transplantation in Children.

Hematopoietic stem cell transplantation (HSCT) is an effective treatment method used in many neoplastic and non-neoplastic diseases that affect the bone marrow, blood cells, and immune system. The procedure is associated with a risk of adverse events, mostly related to the immune response after transplantation. The aim of our research was to identify genes, processes and cellular entities involved in the variety of changes occurring after allogeneic HSCT in children by performing a whole genome expression assessment together with pathway enrichment analysis. We conducted a prospective study of 27 patients (aged 1.5-18 years) qualified for allogenic HSCT. Blood samples were obtained before HSCT and 6 months after the procedure. Microarrays were used to analyze gene expressions in peripheral blood mononuclear cells. This was followed by Gene Ontology (GO) functional enrichment analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, and protein-protein interaction (PPI) analysis using bioinformatic tools. We found 139 differentially expressed genes (DEGs) of which 91 were upregulated and 48 were downregulated. "Blood microparticle", "extracellular exosome", "B-cell receptor signaling pathway", "complement activation" and "antigen binding" were among GO terms found to be significantly enriched. The PPI analysis identified 16 hub genes. Our results provide insight into a broad spectrum of epigenetic changes that occur after HSCT. In particular, they further highlight the importance of extracellular vesicles (exosomes and microparticles) in the post-HSCT immune response.

Comparison of blood pressure values and expression of genes associated with hypertension in children before and after hematopoietic cell transplantation.

Hypertension is a well-known late effect of hematopoietic cell transplantation (HCT), but no markers predicting its development are known. Our aim was to assess short-term blood pressure (BP) values and expressions of hypertension-associated genes as possible markers of hypertension in children treated with HCT. We measured systolic blood pressure (SBP) and diastolic blood pressure (DBP), using both office procedure and ambulatory BP monitoring (ABPM) in children before HCT and after a median of 6 months after HCT. We compared the results with two control groups, one of healthy children and another of children with simple obesity. We also performed microarray analysis of hypertension-associated genes in patients treated with HCT and children with obesity. We found no significant differences in SBP and DBP in patients before and after HCT. We found significant differences in expressions of certain genes in patients treated with HCT compared with children with obesity. We concluded that BP values in short-term follow-up after HCT do not seem to be useful predictors of hypertension as a late effect of HCT. However, over expressions of certain hypertension-associated genes might be used as markers of hypertension as a late effect of HCT if this is confirmed in larger long-term studies.

The Expression of Genes Related to Lipid Metabolism and Metabolic Disorders in Children before and after Hematopoietic Stem Cell Transplantation-A Prospective Observational Study.

Metabolic disorders in children after hematopoietic stem cell transplantation (HSCT) are poorly characterized. However, it is known that dyslipidemia and insulin resistance are particularly common in these patients. We conducted a prospective study of 27 patients treated with HSCT to assess the possibility of predicting these abnormalities. We measured gene expressions using a microarray technique to identify differences in expression of genes associated with lipid metabolism before and after HSCT. In patients treated with HSCT, total cholesterol levels were significantly higher after the procedure compared with the values before HSCT. Microarray analysis revealed statistically significant differences in expressions of three genes, DPP4, PLAG1, and SCD, after applying the Benjamini-Hochberg procedure (pBH < 0.05). In multiple logistic regression, the increase of DPP4 gene expression before HCST (as well as its change between pre- and post-HSCT status) was associated with dyslipidemia. In children treated with HSCT, the burden of lipid disorders in short-term follow-up seems to be lower than before the procedure. The expression pattern of DPP4 is linked with dyslipidemia after the transplantation.

[Central nervous system involvement at diagnosis and at relapse in children with neuroblastoma]. / Zajecie osrodkowego ukladu nerwowego w chwili rozpoznania i we wznowach u dzieci ze zwojakiem zarodkowym wspólczulnym.

Central nervous system (CNS) involvement in the course of neuroblastoma (NBL) in children is relatively rare. However, it seems to become serious clinical problem in the group of patients from high risk group. They presently achieve longer time of survival caused by employment of more intensive treatment modalities. The aim of the study was clinical evaluation of the patients over 1 year of age with stage 4 NBL with CNS involvement, both at diagnosis and at relapse. From 1997 to 2007, 117 patients (age 0.2-13.5 years) started NBL treatment. In 58 children over 1 year, stage 4 of disease was diagnosed. In 4 (6.9%) cases the CNS involvement was found at diagnosis. In 5 patients (8.6%) the isolated relapse in brain was diagnosed. The clinical symptoms caused by increased intracranial pressure were observed in all patients at relapse. In the case of initial involvement no neurological symptoms were observed. All 5 children with CNS involvement as isolated relapse did not present with infiltration of skull bones, whereas at initial diagnosis the brain lesions were continuous with bone metastases. Among 5 patients with isolated relapse 4 died because of NBL progression. Among 4 children with initial CNS involvement 1 died due to haemorrhage to CNS. Probably brain involvement at initial NBL diagnosis is not an additional negative prognostic factor. Because of extremely poor prognosis in patients with CNS relapse it should be advised to consider possible implementation of preventive treatment. It is also necessary to invent new more effective treatment methods.

[Long-term observations of children with acute lymphoblastic leukemia and high leukocytosis treated according to modified "New York" protocols (1987-2003)]. / Wieloletnie obserwacje dziec z ostra bialaczka limfoblastyczna i wysoka liczba krwinek bialych leczonych wedlug zmodyfikowanych protokolow "Nowy Jork" (1987-2003).

Acute lymphoblastic leukemia (ALL) is the most common childhood malignancy. Due to new therapeutic schedules and cooperation between oncological centers it is curable in more than 80% of affected children. For the optimalization of the therapy there is necessary to assess the risk criteria that have influence on the treatment results in the certain groups of patients. Hyperleukocytosis and the age (less than 1 year and more than 10 years) are known as unfavorable risk factors. The study was designed to assess the long-term treatment results in children with ALL and the initial leukocytosis over 50 000/mm3 with the use of the modified "New York" protocols. We present the treatment results of 340 children with ALL treated in nine centers of Polish Pediatric Leukemia/Lymphoma Study Group (PPLLSG) according to three consecutive versions of modified "New York" protocol (group I, II, and III) between 1987 and 2003. Within the analyzed groups the first complete remission (I CR) was achieved in 91%, 95% and 96% of the patients, respectively. Relapses occurred in 37%, 21.5% and 26% of the patients and 3.7%, 1.8% and 5.7% of children died in the I CR due to complications, in the I, II and III therapeutic group, respectively. Obtained 5-and 10-year event-free survival (EFS) were 56% and 53.5% for the group I and 73% and 73% for the group II. Five-year EFS for the group III was 67%. The implementation of the New York protocol in 1987 and New York I in 1997 has improved the treatment results in children with ALL and initial leukocytosis over 50 000/mm3. Protocol New York II did not further improve the treatment results. Among analyzed parameters (age, gender, the initial leukocytosis, the blast cells immunophenotype) only age had the statistical significance. The implementation of modified "New York" protocols has improved the treatment results in children with ALL and initial leukocytosis over 50 000/mm3 compared to previous results.

[Genotyping and minimal residual disease study in children with acute myeloid leukemia: preliminary results]. / Genotypowanie i oznaczania choroby resztkowej u dzieci z ostra bialaczka mieloblastycznq: wstepne wyniki.

The aim of the paper is to present the initial results of molecular examination which was started in 2006 for children with acute myeloid leukemia. Better knowledge of biology of this disease, can result in establishing of new risk factors what allows more precise patient stratification to different therapeutic groups. Study was obtained patients until to 18 years of age treated according to AML-BFM 2004 INTERIM protocol in 14 centers of the Polish Pediatric Leukemia/Lymphoma Study Group. Mononuclear cells were collected from bone marrow on time points established according to the AML-BFM 2004 INTERIM protocol. Collected cells were isolated on Ficoll gradient, and RNA and DNA were isolated using TRIZOL reagent. To synthesize cDNA an amount of 1 mg of total RNA was used. To perform quantitative RT-PCR and RQ-PCR reactions 4 fusion gene transcripts (AML1-ETO, CBFb-MYH11, PML-RARA /subtype bcrl and bcr3/) were used according to the protocol established by Europe Against Cancer Program. An expression of WT1 gene was tested additionally. An analysis of ABL control gene was used to normalize of achieved results. Determination of duplication of FLT3 gene in DNA sample was performed with starters complementary to JM region. Genotyping was performed in 75 patients with acute myeloid leukemia so far. AML1-ETO fusion gene transcript was found in 14 patients (19%). PML-RARA (subtype bcr3) and CBFB-MYH11 gene transcripts were detected in 3 (4%) and 3 (4%) patients, respectively. Duplication of FLT3 gene was found in 4 (5.3%) cases. Between 67 tested children over expression of WT1 was present in 51 patients (76%). Analysis of MRD level in subsequent time points showed systematic decrease of number of fusion gene transcript copies and gene WT1 expression. To establish the rate of molecular marker presence in AML in children and the influence of the presence of MRD on the treatment results as well, the study has to be conducted on a larger group of patients with longer follow-up.

Polymorphisms of SLC19A1 80 G>A, MTHFR 677 C>T, and Tandem TS Repeats Influence Pharmacokinetics, Acute Liver Toxicity, and Vomiting in Children With Acute Lymphoblastic Leukemia Treated With High Doses of Methotrexate.

Introduction: High dose methotrexate (HD-Mtx) is highly effective and significantly improves overall acute lymphoblastic leukemia (ALL) patients survival. The pharmacodynamics of Mtx depends on the polymorphism of genes encoding proteins engaged in the folate metabolism pathway. The aim of the current study is to determine the relationship between variants of folate metabolism-related genes and the frequency of acute toxicities of HD-Mtx. Material and Methods: A group of 133 patients aged 1.5-18.1 years (median: 6.3) was treated in accordance with the ALL-IC-2002 and ALL-IC-2009 protocols. The following polymorphisms were determined: 80 G>A SLC19A1 (solute carrier family 19 member 1; rs1051266) with direct DNA sequencing, as well as 677 C>T MTHFR (methylenetetrahydrofolate reductase; rs1801133) and the tandem repeats of the TS (thymidylate synthase) with PCR technique. HD-Mtx organ toxicities were evaluated based on the laboratory tests results and the National Cancer Institute criteria. Results: In patients with genotypes AA for SLC19A1 and CC or CT for MTHFR Mtx steady state concentrations (Css) and AUCinf were distinctly higher. In patients with genotype 3R/3R for TS initial elimination rate constant was significantly higher (P = 0.003). Patients receiving Mtx at the dose of 5 g/m2 had lower clearance (4.35 vs. 8.92 L/h/m2) as compared to the ones receiving 2 g/m2 that indicates non-linear Mtx elimination at the higher dose. Liver impairment was the most frequently observed toxicity. The homozygous genotype was associated with a significantly higher incidence of hepatic toxicity for both the SLC19A1 (P = 0.037) and TS (P = 0.002). Logistic regression analysis indicated an increased risk of vomiting for the 2R/3R genotype of the TS gene (OR 3.20, 95% CI 1.33-7.68, P = 0.009) and for vomiting and hepatic toxicity for the 3R/3R genotype (vomiting: OR 3.39, 95% CI 1.12-10.23, P = 0.031; liver toxicity: OR 2.28, 95% CI 1.05-4.95, P = 0.038). None of the acute toxicities differed between the analyzed dosing groups. Conclusions: Determination of polymorphisms of SLC19A1, MTHFR, and TS genes might allow for a better prior selection of patients with higher risk of elevated Mtx levels. Our study is the first one to report the increased risk of hepatotoxicity and vomiting in patients with TS polymorphisms.

Genetic Signature of Acute Lymphoblastic Leukemia and Netherton Syndrome Co-incidence-First Report in the Literature.

The aim of the following case report is to provide a description of acute lymphoblastic leukemia (ALL) in a patient with Netherton syndrome (NS). A 15-year-old male with NS was referred with suspicion of acute leukemia. Severe anemia, leukocytosis, thrombocytopenia, and elevated CRP level were demonstrated in pre-hospital laboratory tests. Physical examination revealed generalized ichthyosiform erythroderma. ALL was diagnosed on the basis of bone marrow biopsy. The patient was initially classified as CNS3 status. No signals indicating fusion of BCR/ABL1, ETV6, and RUNX1 genes and MLL gene rearrangement were found in the cytogenetic analysis. The patient was qualified for chemotherapy and treated according to ALL IC-BFM 2009 protocol for high-risk ALL. During induction therapy, severe skin toxicity occurred (WHO grade III), which prompted the modification of treatment down to intermediate-risk strategy. In the course of reinduction therapy, severe chemotherapy-induced adverse drug reactions occurred, including progression of skin toxicity to WHO grade IV. The patient achieved complete remission. In view of life-threatening toxicities and the confirmed complete remission, intensive chemotherapy regimen was discontinued and maintenance treatment was started. Because of the baseline CNS3 status, the patient received cranial radiotherapy. Whole exome sequencing (WES) was used to identify disease-associated mutations. WES revealed two germline mutations: a novel premature termination variant in SPINK5 (p.Cys510*), along with a novel potentially pathogenic variant in NUP214 (p.Arg815Gln). Somatic mutations were known pathogenic variants of JAK2 (p.Arg683Gly), IL17RC (p.Ala303Thr), and potentially pathogenic non-synonymous variants of TTN (p.Gly1091Arg and p.Pro17245Leu), ACTN2 (p.Ile143Leu), TRPV3 (p.Arg729*), and COL7A1 (p.Glu2842fs) genes. Currently, the patient continues maintenance chemotherapy, with stable status of skin lesions and no features of ALL relapse. To our knowledge, this is the first report of ALL in a patient with NS. As has been presented, in such patients, optimal treatment according to the current protocols is extremely difficult. WES was used to confirm the diagnosis of Ph-like ALL in our patient. The detection of JAK2 gene mutation offers the possibility of therapy personalization. A specific signature of rare germline variants and somatic mutations can be proposed as a factor predisposing to the co-incidence of ALL and NS.

Late effects in survivors of childhood acute lymphoblastic leukemia in the context of selected gene polymorphisms.

BACKGROUND: It has been shown that approximately half of survivors of childhood acute lymphoblastic leukemia (ALL) have symptomatic late effects (LE) that may be severe or life-threatening. The aim of our study was to assess the health status of childhood ALL survivors after over 10 years of follow-up and to assess its relationships with gene polymorphisms, numbers and types of LEs, as well as with intensity of chemotherapy and cranial radiotherapy (CRT). METHODS: We conducted a telephone survey in 125 ALL survivors (median time from completion of treatment was 12 years) and compared the results with those obtained in our previous study. Most of the patients were followed-up by local providers. RESULTS: The prevalence of LEs of approximately 50% was similar in both study groups. More than one LE was found in almost 25% of patients. Endocrine LEs were less frequent than in our previous study (44% vs 22%), probably due to underdiagnosis. The prevalence of hepatitis B/C decreased from 30%/50 to 18% (counted together), and prevalence of neurologic LEs decreased from 18 to 6%. The increase in the rate of second malignancies was not significant (2% vs. 3%). Sixty four percent of patients continued their education at the time of the study. Approximately 51% of ALL survivors who have completed their education by the time of the study had no permanent employment, including 4 mothers of infants and 3 persons qualified for a disability living allowance. These employment problems may have been due to cognitive impairment. The offspring of the ALL survivors included 11 children, all of them healthy. Further analysis showed higher prevalence of hepatitis in patients treated with CRT (p = 0.0001). Genetic studies revealed higher prevalence of hepatitis in patients homozygous for the rs9939609A variant of the FTO gene compared with other patients (p = 0.03). Moreover, wild-type rs1137101 polymorphism (Q223R) of the and leptin receptor gene was more frequent in patients with psychological LEs (p = 0.03). CONCLUSIONS: The prevalence of LEs in ALL survivors is of key importance. The transition of childhood ALL survivors from pediatric to adult care should be urgently improved to maintain continued follow-up provide high-quality care. TRIAL REGISTRATION: Bioethics Committee of the Jagiellonian University approved the study protocol. Registration number: KBET/113/B/2006.

[Body fat measurements using bioelectrical impedance in pediatric patientstreated with hematopoietic cell transplantation]. / Pomiary tkanki tluszczowej z zastosowaniem bioimpedancji elektrycznej u dzieci leczonych przeszczepieniem komórek krwiotwórczych.

INTRODUCTION: In patients who have undergone hematopoietic cell transplantation (HCT), the metabolic syndrome may develop without obesity defined by Body Mass Index (BMI). AIM OF THE STUDY: The aim of the study was to compare body fat parameters measured using bioelectrical impedance (BIA) and using standard parameters of obesity in patients treated with HCT and healthy controls. MATERIAL AND METHODS: We compared body fat (BF) and body fat percentage (BF%) measured using BIA in 44 patients before HCT and 28 patients after HCT, versus 26 controls. We also compared BMI and other BIA parameters in these groups of patients. RESULTS: The differences in BF and BF% between the patients before HCT and controls were not significant, while both BF and BF% were significantly lower in patients after HCT than in the control group. No significant differences in standard clinical obesity parameters were found in the patients before HCT, and in the patients after HCT, compared with the controls. The differences in other BIA parameters between the patients before HCT and the controls were not significant, while in the patients after HCT some parameters were significantly lower. CONCLUSION: Significant differences in BF and BF% in the patients after HCT compared with healthy controls suggest that BIA may be useful in screening for body fat abnormalities in patients after HCT.

Association of germline genetic variants in RFC, IL15 and VDR genes with minimal residual disease in pediatric B-cell precursor ALL.

Minimal residual disease (MRD) enables reliable assessment of risk in acute lymphoblastic leukemia (ALL). However, little is known on association between MRD status and germline genetic variation. We examined 159 Caucasian (Slavic) patients with pediatric ALL, treated according to ALL-IC-BFM 2002/2009 protocols, in search for association between 23 germline polymorphisms and MRD status at day 15, day 33 and week 12, with adjustment for MRD-associated clinical covariates. Three variants were significantly associated with MRD: rs1544410 in VDR (MRD-day15); rs1051266 in RFC (MRD-day33, MRD-week12), independently and in an additive effect with rs10519613 in IL15 (MRD-day33). The risk alleles for MRD-positivity were: A allele of VDR (OR = 2.37, 95%CI = 1.07-5.21, P = 0.03, MRD-day15); A of RFC (OR = 1.93, 95%CI = 1.05-3.52, P = 0.03, MRD-day33 and MRD-week12, P < 0.01); A of IL15 (OR = 2.30, 95%CI = 1.02-5.18, P = 0.04, MRD-day33). The risk for MRD-day33-positive status was higher in patients with risk alleles in both RFC and IL15 loci than in patients with risk alleles in one locus or no risk alleles: 2 vs. 1 (OR = 3.94, 95% CI = 1.28-12.11, P = 0.024), 2 vs. 0 (OR = 6.75, 95% CI = 1.61-28.39, P = 0.012). Germline variation in genes related to pharmacokinetics/pharmacodynamics of anti-leukemic drugs and to anti-tumor immunity of the host is associated with MRD status and might help improve risk assessment in ALL.

Genetic Background of Immune Complications after Allogeneic Hematopoietic Stem Cell Transplantation in Children.

Immune reactions are among the most serious complications observed after hematopoietic stem cell transplantation (HSCT) in children. Microarray technique allows for simultaneous assessment of expression of nearly all human genes. The objective of the study was to compare the whole genome expression in children before and after HSCT. A total of 33 children referred for HSCT were enrolled in the study. In 70% of the patients HSCT was performed for the treatment of neoplasms. Blood samples were obtained before HSCT and six months after the procedure. Subsequently, the whole genome expression was assessed in leukocytes using GeneChip Human Gene 1.0 ST microarray. The analysis of genomic profiles before and after HSCT revealed altered expression of 124 genes. Pathway enrichment analysis revealed upregulation of five pathways after HSCT: allograft rejection, graft-versus-host disease, type I diabetes mellitus, autoimmune thyroid disease, and viral myocarditis. The activation of those pathways seems to be related to immune reactions commonly observed after HSCT. Our results contribute to better understanding of the genomic background of the immunologic complications of HSCT.