Neuroblastoma (NBL), one of the main death-causing cancers in children, is known for its remarkable genetic heterogeneity and varied patient outcome spanning from spontaneous regression to widespread disease. Specific copy number variations and single gene rearrangements have been proven to be associated with biological behavior and prognosis; however, there is still an unmet need to enlarge the existing armamentarium of prognostic and therapeutic targets. We performed whole exome sequencing (WES) of samples from 18 primary tumors and six relapse samples originating from 18 NBL patients. Our cohort consists of 16 high-risk, one intermediate, and one very low risk patient. The obtained results confirmed known mutational hotspots in ALK and revealed other non-synonymous variants of NBL-related genes (TP53, DMD, ROS, LMO3, PRUNE2, ERBB3, and PHOX2B) and of genes cardinal for other cancers (KRAS, PIK3CA, and FLT3). Beyond, GOSeq analysis determined genes involved in biological adhesion, neurological cell-cell adhesion, JNK cascade, and immune response of cell surface signaling pathways. We were able to identify novel coding variants present in more than one patient in nine biologically relevant genes for NBL, including TMEM14B, TTN, FLG, RHBG, SHROOM3, UTRN, HLA-DRB1, OR6C68, and XIRP2. Our results may provide novel information about genes and signaling pathways relevant for the pathogenesis and clinical course in high-risk NBL.

Genetic histone variants have been implicated in cancer development and progression. Mutations affecting the histone 3 (H3) family, H3.1 (encoded by HIST1H3B and HIST1H3C) and H3.3 (encoded by H3F3A), are mainly associated with pediatric brain cancers. While considered poor prognostic brain cancer biomarkers in children, more recent studies have reported H3 alterations in adult brain cancer as well. Here, we established reliable droplet digital PCR based assays to detect three histone mutations (H3.3-K27M, H3.3-G34R, and H3.1-K27M) primarily linked to childhood brain cancer. We demonstrate the utility of our assays for sensitively detecting these mutations in cell-free DNA released from cultured diffuse intrinsic pontine glioma (DIPG) cells and in the cerebral spinal fluid of a pediatric patient with DIPG. We further screened tumor tissue DNA from 89 adult patients with glioma and 1 with diffuse hemispheric glioma from Southwestern Sydney, Australia, an ethnically diverse region, for these three mutations. No histone mutations were detected in adult glioma tissue, while H3.3-G34R presence was confirmed in the diffuse hemispheric glioma patient.

BackgroundThere is an increasing awareness of the importance of the gut microbiome in disease progression and the maintenance of human health. However, links between the microbiome and cancer onset remain relatively unexplored. This is especially the case for childhood cancers, which although rare, are the predominant cause of death among children in Western countries.MethodsFecal samples were collected from patients, before the onset of treatment, by the Norwegian Childhood Cancer Biobank in Oslo and from children attending kindergartens in Oslo, Norway. Using 16S rRNA gene amplicon sequencing, we compared the gut microbiome compositions of the children diagnosed with cancer with children attending kindergarten.ResultsWe observed significant differences in the relative abundances of several taxa, including a striking depletion of Faecalibacterium prausnitzii, an important taxa linked to gut health maintenance.ConclusionsOur observations provide evidence that the gut microbiome may play an important role in physiological changes associated with the onset of childhood cancer. However, further studies should be designed in order to validate our findings. Furthermore, these results suggest that variations in the microbial community could potentially be used as an early indicator of childhood cancer.

Birth asphyxia is the leading cause of death and disability in young children worldwide. Long non-coding RNAs (lncRNAs) may provide novel targets and intervention strategies due to their regulatory potential, as demonstrated in various diseases and conditions. We investigated cardinal lncRNAs involved in oxidative stress, hypoxia, apoptosis, and DNA damage using a piglet model of perinatal asphyxia. A total of 42 newborn piglets were randomized into 4 study arms: (1) hypoxia–normoxic reoxygenation, (2) hypoxia–3 min of hyperoxic reoxygenation, (3) hypoxia–30 min of hyperoxic reoxygenation, and (4) sham-operated controls. The expression of lncRNAs BDNF-AS, H19, MALAT1, ANRIL, TUG1, and PANDA, together with the related target genes VEGFA, BDNF, TP53, HIF1α, and TNFα, was assessed in the cortex, the hippocampus, the white matter, and the cerebellum using qPCR and Droplet Digital PCR. Exposure to hypoxia–reoxygenation significantly altered the transcription levels of BDNF-AS, H19, MALAT1, and ANRIL. BDNF-AS levels were significantly enhanced after both hypoxia and subsequent hyperoxic reoxygenation, 8% and 100% O2, respectively. Our observations suggest an emerging role for lncRNAs as part of the molecular response to hypoxia-induced damages during perinatal asphyxia. A better understanding of the regulatory properties of BDNF-AS and other lncRNAs may reveal novel targets and intervention strategies in the future.

Background Since the discovery more than half a century ago, cell-free DNA (cfDNA) has become an attractive objective in multiple diagnostic, prognostic, and monitoring settings. However, despite the increasing number of cfDNA applications in liquid biopsies, we still lack a comprehensive understanding of the nature of cfDNA including optimal assessment. In the presented study, we continued testing and validation of common techniques for cfDNA extraction and quantification (qRT-PCR or droplet digital PCR) of nuclear- and mitochondrial cfDNA (ncfDNA and mtcfDNA) in blood, using a piglet model of perinatal asphyxia to determine potential temporal and quantitative changes at the levels of cfDNA. Methods and Results Newborn piglets (n = 19) were either exposed to hypoxia (n = 11) or were part of the sham-operated control group (n = 8). Blood samples were collected at baseline (= start) and at the end of hypoxia or at 40–45 min for the sham-operated control group. Applying the qRT-PCR method, ncfDNA concentrations in piglets exposed to hypoxia revealed an increasing trend from 7.1 ng/ml to 9.5 ng/ml for HK2 (hexokinase 2) and from 4.6 ng/ml to 7.9 ng/ml for β-globulin, respectively, whereas the control animals showed a more balanced profile. Furthermore, median levels of mtcfDNA were much higher in comparison to ncfDNA, but without significant differences between intervention versus the control group. Conclusions Both, qRT-PCR and the droplet digital PCR technique identified overall similar patterns for the concentration changes of cfDNA; but, the more sensitive digital PCR methodology might be required to identify minimal responses.

Abstract Background The rapidly expanding era of “omics” research is highly dependent on the availability of quality‐proven biological material, especially for rare conditions such as pediatric malignancies. Professional biobanks provide such material, focusing on standardized collection and handling procedures, distinctive quality measurements, traceability of storage conditions, and accessibility. For pediatric malignancies, traditional tumor biobanking is challenging due to the rareness and limited amount of tissue and blood samples. The higher molecular heterogeneity, lower mutation rates, and unique genomic landscapes, however, renders biobanking of this tissue even more crucial. Aim The aim of this study was to test and establish methods for a prospective and centralized biobank for infants, children, and adolescents up to 18 years of age diagnosed with cancer in Norway. Methods Obtain judicial and ethical approvals and administration through a consortium, steering committee, and advisory board. Develop pipelines including SOPs for all aspects in the biobank process, including collection, processing and storing of samples and data, as well of quality controlling, safeguarding, distributing, and transport. Results The childhood cancer biobanking started at Oslo University Hospital in March 2017 and was from 2019 run as a national Norwegian Childhood Cancer Biobank. Informed consent and biological samples are collected regionally and stored centrally. Approximately 12 000 samples from 510 patients and have been included by January 1, 2021, representing a 96% consent and participation rate among our newly diagnosed patients. Conclusion A well‐functioning nationwide collection and centralized biobank with standardized procedures and national storage for pediatric malignancies has been established with a high acceptance among families.

Background Retinal gene expression pattern is severely altered after exposition to hyperoxia in mice with oxygen-induced retinopathy (OIR), a common model of retinopathy of prematurity. Gene ontology and signaling pathway analyses may add new insights into a better understanding of the pathogenesis of this disease. Methods Seven-day-old C57BL/6J mice ( n = 60) were exposed to 75% oxygen for 5 days and then recovered in room air. The controls ( n = 60) were kept in the normoxic conditions. Retinas were harvested immediately following hyperoxia, during the phase of maximal neovascularization, and at the time of neovascularization regression. The retinal RNA samples were evaluated for gene expression using mouse gene expression microarrays. DAVID annotation tools were used for gene ontology and pathway analyses. Results The most significantly enriched signaling pathways during the neovascularization phase of OIR were: focal adhesion; ECM–receptor interaction; PI3K-Akt; oxidative phosphorylation; and Alzheimer’s, Parkinson’s and Huntington’s disease signaling pathways. Genes involved in apoptosis, cell proliferation, cell differentiation, and immune responses were associated with neovascularization regression. Conclusions Performed analyses revealed the possible involvement of various signaling pathways in OIR pathomechanism, mostly specific to the OIR phase. Dysregulation of genes involved in oxidative phosphorylation may have an impact on neovascularization development.

Background We aimed to identify global blood and retinal gene expression patterns in murine oxygen-induced retinopathy (OIR), a common model of retinopathy of prematurity, which may allow better understanding of the pathogenesis of this severe ocular prematurity complication and identification of potential blood biomarkers. Methods A total of 120 C57BL/6J mice were randomly divided into an OIR group, in which 7-day-old pups were maintained in 75% oxygen for 5 days, or a control group. RNA was extracted from the whole-blood mononuclear cells and retinal cells on days 12, 17, and 28. Gene expression in the RNA samples was evaluated with mouse gene expression microarrays. Results There were 38, 1370 and 111 genes, the expression of which differed between the OIR and control retinas on days 12, 17, and 28, respectively. Gene expression in the blood mononuclear cells was significantly altered only on day 17. Deptor and Nol4 genes showed reduced expression both in the blood and retinal cells on day 17. Conclusion There are sustained marked changes in the global pattern of gene expression in the OIR mice retinas. An altered expression of Deptor and Nol4 genes in the blood mononuclear cells requires further investigation as they may indicate retinal neovascularization.

BACKGROUND:Bronchopulmonary dysplasia (BPD) is a common cause of abrupted lung development after preterm birth. BPD may lead to increased rehospitalization, more severe and frequent respiratory infections, and life-long reduced lung function. The gene regulation in lungs with BPD is complex, with various genetic and epigenetic factors involved.OBJECTIVES:The aim of this study was to examine the regulatory relation between gene expression and the epigenome (DNA methylation) relevant for the immune system after hyperoxia followed by a recovery period in air using a mouse model of BPD.METHODS:Newborn mice pups were subjected to an immediate hyperoxic condition from birth and kept at 85% O2 levels for 14 days followed by a 14-day period in room air. Next, mice lung tissue was used for RNA and DNA extraction with subsequent microarray-based assessment of lung transcriptome and supplementary methylome analysis.RESULTS:The immune system-related transcriptomeregulation was affected in mouse lungs after hyperoxia. A high proportion of genes relevant in the immune system exhibited significant expression alterations, e.g., B cell-specific genes central to the cytokine-cytokine receptor interaction, the PI3K-AKT, and the B cell receptor signaling pathways. The findings were accompanied by significant DNA hypermethylation observed in the PI3K-AKT pathway and immune system-relevant genes.CONCLUSIONS:Oxygen damage could be partly responsible for the increased susceptibility and abnormal response to respiratory viruses and infections seen in premature babies with BPD through dysregulated genes.

In this study, we aimed to analyze differences in plasma protein abundances between infants with and without bronchopulmonary dysplasia (BPD), to add new insights into a better understanding of the pathogenesis of this disease. Cord and peripheral blood of neonates (≤ 30 weeks gestational age) was drawn at birth and at the 36th postmenstrual week (36 PMA), respectively. Blood samples were retrospectively subdivided into BPD(+) and BPD(−) groups, according to the development of BPD. Children with BPD were characterized by decreased afamin, gelsolin and carboxypeptidase N subunit 2 levels in cord blood, and decreased galectin-3 binding protein and hemoglobin subunit gamma-1 levels, as well as an increased serotransferrin abundance in plasma at the 36 PMA. BPD development is associated with the plasma proteome changes in preterm infants, adding further evidence for the possible involvement of disturbances in vitamin E availability and impaired immunological processes in the progression of prematurity pulmonary complications. Moreover, it also points to the differences in proteins related to infection resistance and maintaining an adequate level of hematocrit in infants diagnosed with BPD.

Cell free DNA (cfDNA) in plasma has been described as a potential diagnostic indicator for a variety of clinical conditions, including neonatal hypoxia. Neonatal hypoxia or perinatal asphyxia is a severe medical condition caused by a temporary interruption in oxygen availability during birth. Previously, we have reported temporal changes of cfDNA detected in blood in a newborn piglet model of perinatal asphyxia. However, cfDNA can also be found in other body liquids, opening for a less invasive diagnostic prospective. The objective of this study was to test and establish a reliable method for the isolation and quantification of cfDNA from urine and to explore changes in the quantities of cfDNA using a newborn piglet model of asphyxia. Animals were exposed to hypoxia-reoxygenation (n = 6), hypoxia-reoxygenation + hypothermia (n = 6) or were part of the sham-operated control group (n = 6) and urine samples (n = 18) were collected at 570 minutes post-intervention. Two alternative applications of cfDNA measurement were tested, an indirect method comprising a centrifugation step together with DNA extraction with magnetic beads versus a direct assessment based on two centrifugation steps. CfDNA concentrations were determined by a fluorescent assay using PicoGreen and by qRT-PCR. Genomic (gDNA) and mitochondrial DNA (mtDNA) cfDNA were determined in parallel, taking into account potential differences in the rates of damages caused by oxidative stress. In contrast to previous publications, our results indicate that the direct method is insufficient. Application of the indirect method obtained with the fluorescence assay revealed mean cfDNA levels (SD) of 1.23 (1.76) ng/ml for the hypoxia samples, 4.47 (6.15) ng/ml for the samples exposed to hypoxia + hypothermia and 2.75 (3.62) ng/ml for the control animals. The mean cfDNA levels in piglets exposed to hypoxia + hypothermia revealed significantly higher cfDNA amounts compared to mean cfDNA levels in the samples purely exposed to hypoxia (p < 0.05); however, no significant difference could be determined when compared to the control group (p = 0.09). Application of the indirect method by qRT-PCR revealed mean cfDNA levels of mtDNA and gDNA at the detection limit of the technique and thus no reliable statistics could be performed between the observed cfDNA levels in the investigated groups. The methodology for detection and monitoring of cfDNA in urine has to be further optimized before it can be applied in a clinical setting in the future.

Perinatal asphyxia is a severe medical condition resulting from oxygen deficiency (hypoxia) at the time of birth, causing worldwide approximately 680,000 newborn deaths every year. Better prediction of severity of damages including early biomarkers is highly demanded. Elevated levels of circulating cell-free DNA (cfDNA) in blood have been reported for a range of different diseases and conditions, including cancer and prematurity. The objective of this study was to validate methods for assessing cfDNA in blood and cerebrospinal fluid (CSF) and to explore temporal variations in a piglet model of neonatal hypoxia-reoxygenation. Different cfDNA extraction methods in combination with cfDNA detection systems were tested, including a fluorescent assay using SYBR Gold and a qRT-PCR-based technique. Newborn piglets (n = 55) were exposed to hypoxia-reoxygenation, hypoxia-reoxygenation and hypothermia, or were part of the sham-operated control group. Blood was sampled at baseline and at post-intervention, further at 30, 270, and 570 minutes after the end of hypoxia. Applying the fluorescent method, cfDNA concentration in piglets exposed to hypoxia (n = 32) increased from 36.8±27.6 ng/ml prior to hypoxia to a peak level of 61.5±54.9 ng/ml after the intervention and deceased to 32.3±19.1 ng/ml at 570 minutes of reoxygenation, whereas the group of sham-operated control animals (n = 11) revealed a balanced cfDNA profile. Animals exposed to hypoxia and additionally treated with hypothermia (n = 12) expressed a cfDNA concentration of 54.4±16.9 ng/ml at baseline, 39.2±26.9 ng/ml at the end of hypoxia, and of 41.1±34.2 ng/ml at 570 minutes post-intervention. Concentrations of cfDNA in the CSF of piglets exposed to hypoxia revealed at post-intervention higher levels in comparison to the controls. However, these observations were only tendencies and not significant. In a first methodological proof-of-principle study exploring cfDNA using a piglet model of hypoxia-reoxygenation variations in the temporal patterns suggest that cfDNA might be an early indicator for damages caused by perinatal asphyxia.

Purpose Retinopathy of prematurity (ROP) is a vision-threatening complication of a premature birth, in which the etiology still remains unclear. Importantly, the molecular processes that govern these effects can be investigated in a perturbed plasma proteome composition. Thus, plasma proteomics may add new insights into a better understanding of the pathogenesis of this disease. Methods The cord and peripheral blood of neonates (≤30 weeks gestational age) was drawn at birth and at the 36th postmenstrual week (PMA), respectively. Blood samples were retrospectively subdivided into ROP(+) and ROP(-) groups, according to the development of ROP. Results The quantitative analysis of plasma proteome at both time points revealed 30 protein abundance changes between ROP(+) and ROP(-) groups. After standardization to gestational age, children who developed ROP were characterized by an increased C3 complement component and fibrinogen level at both analyzed time points. Conclusions Higher levels of the complement C3 component and fibrinogen, present in the cord blood and persistent to 36 PMA, may indicate a chronic low-grade systemic inflammation and hypercoagulable state that may play a role in the development of ROP.

Objective In the presented study, we aimed to systematically analyze plasma proteomes in cord blood samples from preterm infants stratified by their gestational age to identify proteins and related malfunctioning pathways at birth, possibly contributing to the complications observed among preterm infants. Study design Preterm newborns were enrolled of three subgroups with different gestation age: newborns born ≤26 (group 1), between 27 and 28 (group 2) and between 29 and 30 (group 3) weeks of gestation, respectively, and compared to the control group of healthy, full-term newborns in respect to their plasma proteome composition. Result Preterm delivery is associated with multiple protein abundance changes in plasma related to a plethora of processes, including inflammation and immunomodulation, coagulation, and complement activation as some key features. Conclusion Plasma proteome analysis revealed numerous gestation-age-dependent protein abundance differences between term and preterm infants, which highlight key dysregulated pathways and potential new protein treatment targets.

Background. After perinatal asphyxia, the cerebellum presents more damage than previously suggested. Objectives. To explore if the antioxidant N-acetylcysteine amide (NACA) could reduce cerebellar injury after hypoxia-reoxygenation in a neonatal pig model. Methods. Twenty-four newborn pigs in two intervention groups were exposed to 8% oxygen and hypercapnia, until base excess fell to −20 mmol/l or the mean arterial blood pressure declined to <20 mmHg. After hypoxia, they received either NACA (NACA group, n=12) or saline (vehicle-treated group, n=12). One sham-operated group (n=5) served as a control and was not subjected to hypoxia. Observation time after the end of hypoxia was 9.5 hours. Results. The intranuclear proteolytic activity in Purkinje cells of asphyxiated vehicle-treated pigs was significantly higher than that in sham controls (p=0.03). Treatment with NACA was associated with a trend to decreased intranuclear proteolytic activity (p=0.08), There were significantly less mutations in the mtDNA of the NACA group compared with the vehicle-treated group, 2.0 × 10−4 (±2.0 × 10−4) versus 4.8 × 10−5(±3.6 × 10−4, p<0.05). Conclusion. We found a trend to lower proteolytic activity in the core of Purkinje cells and significantly reduced mutation rate of mtDNA in the NACA group, which may indicate a positive effect of NACA after neonatal hypoxia. Measuring the proteolytic activity in the nucleus of Purkinje cells could be used to assess the effect of different neuroprotective substances after perinatal asphyxia.

Objective: To examine the gene expression regarding pulmonary vascular disease in experimental bronchopulmonary dysplasia in young mice. Premature delivery puts babies at risk of severe complications. Bronchopulmonary dysplasia (BPD) is a common complication of premature birth leading to lifelong affection of pulmonary function. BPD is recognized as a disease of arrested alveolar development. The disease process is not fully described and no complete cure or prevention is known. The focus of interest in the search for treatment and prevention of BPD has traditionally been at airspace level; however, the pulmonary vasculature is increasingly acknowledged in the pathology of BPD. The aim of the investigation was to study the gene expression in lungs with BPD with regards to pulmonary vascular disease (PVD). Methods: We employed a murine model of hyperoxia-induced BPD and gene expression microarray technique to determine the mRNA expression in lung tissue from young mice. We combined gene expression pathway analysis and analyzed the biological function of multiple single gene transcripts from lung homogenate to study the PVD relevant gene expression. Results: There were n = 117 significantly differentially regulated genes related to PVD through down-regulation of contractile elements, up- and down-regulation of factors involved in vascular tone and tissue-specific genes. Several genes also allowed for pinpointing gene expression differences to the pulmonary vasculature. The gene Nppa coding for a natriuretic peptide, a potent vasodilator, was significantly down-regulated and there was a significant up-regulation of Pde1a (phosphodiesterase 1A), Ptger3 (prostaglandin e receptor 3), and Ptgs1 (prostaglandin-endoperoxide synthase one). Conclusion: The pulmonary vasculature is affected by the arrest of secondary alveolarization as seen by differentially regulated genes involved in vascular tone and pulmonary vasculature suggesting BPD is not purely an airspace disease. Clues to prevention and treatment may lie in the pulmonary vascular system.

BACKGROUND:In this study, we aimed to analyze time-resolved plasma proteome changes in preterm neonates stratified by their gestational age to detect malfunctioning pathways that derive from the systemic immaturity of the neonate and to highlight those that are differentially regulated during the early development.METHODS:Preterm newborns were enrolled in three subgroups with different gestational ages: before 26 weeks of gestation (group 1), between 27 and 28 weeks of gestation (group 2), and between 29 and 30 (group 3) weeks of gestation. Plasma protein abundances were assessed at two time points (at preterm delivery and at the 36th week of post-menstrual age) by quantitative proteomics.RESULT:The quantitative analysis of plasma proteome in preterm infants revealed a multitude of time-related differences in protein abundances between the studied groups. We report protein changes in several functional domains, including inflammatory domains, immunomodulatory factors, and coagulation regulators as key features, with important gestational age-dependent hemopexin induction.CONCLUSION:The global trend emerging from our data, which can collectively be interpreted as a progression toward recovery from the perinatal perturbations, highlights the profound impact of gestation duration on the ability to bridge the gap in systemic homeostasis after preterm labor.

Introduction: Oxidative stress may have detrimental effects on different structures of the cells, such as the DNA. Recently, we have published a study demonstrating that N-Acetylcysteine amide (NACA) displayed anti-inflammatory properties on the brain after exposure to oxidative stress in an established neonatal piglet model, imitating perinatal asphyxia. As different clinical studies have shown an association between the severity of hypoxic-ischemic encephalopathy and damage of the kidneys, we investigated a possible protective effect of NACA against H2O2-induced oxidative stress using a porcine epithelial-like embryonic kidney cell line (EFN-R). Objective: To investigate a potential protective effect of NACA on cells of a porcine embryonic kidney cell line exposed to H2O2. Methods: We subjected the cells to different concentrations of H2O2 for variable time periods, seeking the optimal dose-response for the experiments. Based on the results of these investigations, we exposed the cells to 100 μMol of H2O2 and/or 750 μM of NACA for 24 hours. Some of the cells would receive NACA either one hour before or one hour after exposure to H2O2. Results: The viability of the investigated EFN-R cells revealed that both, the group treated with NACA before exposure to H2O2 and the group treated with NACA after exposure to H2O2, exhibited significantly higher cell viability compared to the H2O2 group (p < 0.001 and p < 0.01, respectively). Discussion: The increased viability of the cells may indicate that NACA could play an important role in reducing oxidative stress. Taking the results from our previous study into consideration, our findings may strengthen the theory that NACA may have organ protective properties for neonates exposed to oxidative stress.

BACKGROUND:There is a lack of reliable biomarkers that can identify and grade acute hypoxic-ischemic encephalopathy in newborns. MicroRNAs (miRNA) are short, non-coding strands of RNA that are released into the circulation in response to tissue stress and injury. Some miRNAs are highly tissue specific and thus may potentially be non-invasive biomarkers of neonatal hypoxic-ischemic brain injury.OBJECTIVE:The aim of this study was to characterize the temporal expression of selected circulating miRNAs in a clinically relevant piglet model of neonatal hypoxia-ischemia (HI).METHODS:A total of 13 anesthetized newborn piglets were randomized to either a control group (n = 5) or transient global HI group (n = 8). HI was achieved by ventilation with 8% oxygen until the point of severe acidosis (arterial base excess ≤-20 mmol/l) and/or hypotension (mean arterial blood pressure ≤20 mm Hg) was reached. Plasma was sampled at baseline, at the end of HI and 0.5, 3.5 and 9.5 h after HI. MiRNA expression was measured by qRT-PCR.RESULTS:Compared to baseline, miR-374a increased during HI (p = 0.01), remained elevated at 0.5 h after HI (p = 0.02) and was downregulated at 9.5 h after HI (p = 0.02). MiR-210 increased during HI (p = 0.02) and rapidly normalized by 0.5 h after HI. MiR-124 and miR-125b did not exhibit significant alterations. Correlations were observed between miR-374a, arterial pH, base excess and lactate levels, and between miR-210 and pO2 (p < 0.05).CONCLUSIONS:Our data suggest that miR-374a and miR-210 are important regulators in neonatal HI and might have a place as biomarkers in this setting.