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1.
J Med Genet ; 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33257509

RESUMO

Strabismus is a common condition, affecting 1%-4% of individuals. Isolated strabismus has been studied in families with Mendelian inheritance patterns. Despite the identification of multiple loci via linkage analyses, no specific genes have been identified from these studies. The current study is based on a seven-generation family with isolated strabismus inherited in an autosomal dominant manner. A total of 13 individuals from a common ancestor have been included for linkage analysis. Among these, nine are affected and four are unaffected. A single linkage signal has been identified at an 8.5 Mb region of chromosome 14q12 with a multipoint LOD (logarithm of the odds) score of 4.69. Disruption of this locus is known to cause FOXG1 syndrome (or congenital Rett syndrome; OMIM #613454 and *164874), in which 84% of affected individuals present with strabismus. With the incorporation of next-generation sequencing and in-depth bioinformatic analyses, a 4 bp non-coding deletion was prioritised as the top candidate for the observed strabismus phenotype. The deletion is predicted to disrupt regulation of FOXG1, which encodes a transcription factor of the Forkhead family. Suggestive of an autoregulation effect, the disrupted sequence matches the consensus FOXG1 and Forkhead family transcription factor binding site and has been observed in previous ChIP-seq studies to be bound by Foxg1 in early mouse brain development. Future study of this specific deletion may shed light on the regulation of FOXG1 expression and may enhance our understanding of the mechanisms contributing to strabismus and FOXG1 syndrome.

2.
Artigo em Inglês | MEDLINE | ID: mdl-33006916

RESUMO

The clinical implementation of pharmacogenetic biomarkers continues to grow as new genetic variants associated with drug outcomes are discovered and validated. The number of drug labels that contain pharmacogenetic information also continues to expand. Published, peer-reviewed clinical practice guidelines have also been developed to support the implementation of pharmacogenetic tests. Incorporating pharmacogenetic information into health care benefits patients as well as clinicians by improving drug safety and reducing empiricism in drug selection. Barriers to the implementation of pharmacogenetic testing remain. This review explores current pharmacogenetic implementation initiatives with a focus on the challenges of pharmacogenetic implementation and potential opportunities to overcome these challenges. Expected final online publication date for the Annual Review of Pharmacology and Toxicology, Volume 61 is January 7, 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

3.
Hum Mol Genet ; 29(16): 2788-2802, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32898862

RESUMO

Huntington disease (HD) is a neurodegenerative disorder that is caused by a CAG repeat expansion in HTT. The length of this repeat, however, only explains a proportion of the variability in age of onset in patients. Genome-wide association studies have identified modifiers that contribute toward a proportion of the observed variance. By incorporating tissue-specific transcriptomic information with these results, additional modifiers can be identified. We performed a transcriptome-wide association study assessing heritable differences in genetically determined expression in diverse tissues, with genome-wide data from over 4000 patients. Functional validation of prioritized genes was undertaken in isogenic HD stem cells and patient brains. Enrichment analyses were performed with biologically relevant gene sets to identify the core pathways. HD-associated gene coexpression modules were assessed for associations with neurological phenotypes in an independent cohort and to guide drug repurposing analyses. Transcriptomic analyses identified genes that were associated with age of HD onset and displayed colocalization with gene expression signals in brain tissue (FAN1, GPR161, PMS2, SUMF2), with supporting evidence from functional experiments. This included genes involved in DNA repair, as well as novel-candidate modifier genes that have been associated with other neurological conditions. Further, cortical coexpression modules were also associated with cognitive decline and HD-related traits in a longitudinal cohort. In summary, the combination of population-scale gene expression information with HD patient genomic data identified novel modifier genes for the disorder. Further, these analyses expanded the pathways potentially involved in modifying HD onset and prioritized candidate therapeutics for future study.

4.
Curr Opin Pediatr ; 32(5): 646-653, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32796162

RESUMO

PURPOSE OF REVIEW: Adverse drug reactions (ADRs) are a serious burden and can negatively impact patient quality of life. One of these ADRs, anthracycline-induced cardiotoxicity (ACT), occurs in up to 65% of treated patients and can lead to congestive heart failure. Pharmacogenetic studies have helped to reveal the mechanisms of ACT and, consequently, inform current strategies to prevent ACT in the clinic. RECENT FINDINGS: Many pharmacogenetic studies have been conducted for ACT, but few have led to the development of clinical practice guidelines and clinical genetic testing for ACT. This is, in part, because of lack of replication in independent patient cohorts and/or validation of an affected biological pathway. Recent advances in pharmacogenetic studies have been made through the use of novel methods that directly implicate dysregulated genes and perturbed biological pathways in response to anthracycline treatment. SUMMARY: Furthering the understanding of the genetics and altered biological pathways of ACT through these novel methods can inform clinical treatment strategies and enable refinement of current clinical practice guidelines. This can therefore lead to improvement in clinical pharmacogenetic testing for further reduction of the incidence of ACT in pediatric cancer patients taking anthracyclines.

5.
Hum Gene Ther ; 31(15-16): 794-807, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32586150

RESUMO

Recent advances in genome sequencing have greatly improved our ability to understand and identify the causes of genetic diseases. However, there remains an urgent need for innovative, safe, and effective treatments for these diseases. CRISPR-based genome editing systems have become important and powerful tools in the laboratory, and efforts are underway to translate these into patient therapies. Therapeutic base editing is one form of genome engineering that has gained much interest because of its simplicity, specificity, and effectiveness. Base editors are a fusion of a partially deactivated Cas9 enzyme with nickase function, together with a base-modifying enzyme. They are capable of precisely targeting and repairing a pathogenic mutation to restore the normal function of a gene, ideally without disturbing the rest of the genome. In the past year, research has identified new safety concerns of base editors and sparked new innovations to improve their safety. In this review, we provide an overview of the recent advances in the safety and effectiveness of therapeutic base editors and prime editing.

6.
JAMA Netw Open ; 3(5): e203639, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32383745

RESUMO

Importance: Few multicenter pediatric studies have comprehensively described the epidemiologic characteristics of cisplatin-associated acute kidney injury using standardized definitions. Objective: To examine the rate of and risk factors associated with acute kidney injury among children receiving cisplatin infusions. Design, Setting, and Participants: This prospective cohort study examined children (aged <18 years) recruited from May 23, 2013, to March 31, 2017, at 12 Canadian pediatric academic health centers who were receiving 1 or more cisplatin infusion. Children whose estimated or measured glomerular filtration rate (GFR) was less than 30 mL/min/1.73 m2 or who had received a kidney transplant were excluded. Data analysis was performed from January 3, 2018, to September 20, 2019. Exposures: Cisplatin infusions. Main Outcomes and Measures: The primary outcome was acute kidney injury during cisplatin infusion, defined using a Kidney Disease: Improving Global Outcomes serum creatinine criteria-based definition (stage 1 or higher). The secondary outcome was acute kidney injury defined by electrolyte criteria from the National Cancer Institute Common Terminology Criteria for Adverse Events (grade 1 or higher). Assessments occurred at early (first or second cycle) and late (last or second to last cycle) cisplatin infusions. Results: A total of 159 children (mean [SD] age at early cisplatin infusion, 7.2 [5.3] years; 80 [50%] male) participated. The most common diagnoses were central nervous system tumors (58 [36%]), neuroblastoma (43 [27%]), and osteosarcoma (33 [21%]). Acute kidney injury (by serum creatinine level increase) occurred in 48 of 159 patients (30%) at early cisplatin infusions and 23 of 143 patients (16%) at late cisplatin infusions. Acute kidney injury (by electrolyte abnormalities) occurred in 106 of 159 patients (67%) at early cisplatin infusion and 100 of 143 patients (70%) at late cisplatin infusions. Neuroblastoma diagnosis and higher precisplatin GFR were independently associated with acute kidney injury (serum creatinine level increase) at early cisplatin infusions (adjusted odds ratio [aOR] for neuroblastoma vs other, 3.25; 95% CI, 1.18-8.95; aOR for GFR, 1.01; 95% CI, 1.00-1.03) and late cisplatin infusions (aOR for neuroblastoma vs other, 6.85; 95% CI, 1.23-38.0; aOR for GFR, 1.01; 95% CI, 1.00-1.03). Higher cisplatin infusion dose was also independently associated with acute kidney injury (serum creatinine level increase) at later cisplatin infusions (aOR, 1.05; 95% CI, 1.01-1.10). Conclusions and Relevance: The findings suggest that acute kidney injury is common among children receiving cisplatin infusions and that rate and risk factors differ at earlier vs later infusions. These results may help with risk stratification with a goal of risk reduction.


Assuntos
Lesão Renal Aguda/epidemiologia , Antineoplásicos/efeitos adversos , Cisplatino/efeitos adversos , Lesão Renal Aguda/induzido quimicamente , Adolescente , Canadá/epidemiologia , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Estudos Prospectivos , Fatores de Risco
9.
Pediatr Hematol Oncol ; 37(1): 15-28, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31682156

RESUMO

Vincristine-induced peripheral neuropathy (VIPN) is a serious and pervasive problem, affecting 12-78% of pediatric patients, based on retrospective studies. The study objective was to prospectively collect a cohort of well-phenotyped patients receiving vincristine in order to accurately classify and grade their neurotoxicity. All children in British Columbia with leukemia or lymphoma requiring vincristine between 2013 and 2016 were approached for consent. Those recruited were assessed by occupational and physiotherapists at baseline, mid and endpoint of their treatment. Assessments included the Bruininks-Oseretsky Test of Motor Proficiency - 2nd ed. (BOT-2), strength, "Timed up and go" test and vibration sensibility. Seventy-two patients consented (age: 2.0-18.7 years). The majority were below average for age on one or more BOT-2 domains at midpoint (N = 32/45, 71%), which decreased by the endpoint (N = 19/41, 46%, p = .049). Six patients showed severe VIPN throughout treatment (N = 6/53, 11%), defined as a BOT-2 score well below average. Muscle strength for wrist extension/flexion, anterior tibialis and peronei decreased significantly between baseline (Median = 5) and midpoint (Median = 4), with no significant change noted by endpoint. Most patients had normal vibration sensibility in lower (N = 30/60, 50%) and upper limbs (N = 26/38, 68%). In conclusion, with no differences between time points. VIPN is highly prevalent among patients with pediatric cancer, causing significant morbidity and functional deficits. Identification of risk factors would allow for resource appropriation to patients at higher risk, as well as potentially permitting dose escalation in patients with low toxicity to improve survival.


Assuntos
Doenças do Sistema Nervoso Periférico/induzido quimicamente , Vincristina/efeitos adversos , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Masculino , Estudos Prospectivos
10.
Emotion ; 20(5): 734-749, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31021112

RESUMO

Who benefits most from helping others? Previous research suggests that common polymorphisms of the oxytocin receptor gene (OXTR) predict whether people behave generously and experience increases in positive mood in response to socially focused experiences in daily life. Building on these findings, we conducted an experiment with a large, ethnically homogenous sample (N = 437) to examine whether individual differences in three frequently studied single nucleotide polymorphisms of OXTR (rs53576, rs2268498, rs2254298) also predict differences in the positive mood benefits of financial generosity. Consistent with past research, participants who were randomly assigned to purchase items for others (vs. themselves) reported greater positive affect. Contrary to predictions, using Bayesian statistics, we found conclusive evidence that the benefits of generosity were not moderated by individual differences in OXTR single nucleotide polymorphisms. The current work highlights the importance of publishing null results to build cumulative knowledge linking neurobiological factors to positive emotional experiences. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Assuntos
Afeto/fisiologia , Emoções/fisiologia , Polimorfismo de Nucleotídeo Único/genética , Receptores de Ocitocina/genética , Comportamento Social , Feminino , Humanos , Masculino
11.
Am J Hum Genet ; 105(3): 534-548, 2019 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-31422819

RESUMO

Early-infantile encephalopathies with epilepsy are devastating conditions mandating an accurate diagnosis to guide proper management. Whole-exome sequencing was used to investigate the disease etiology in four children from independent families with intellectual disability and epilepsy, revealing bi-allelic GOT2 mutations. In-depth metabolic studies in individual 1 showed low plasma serine, hypercitrullinemia, hyperlactatemia, and hyperammonemia. The epilepsy was serine and pyridoxine responsive. Functional consequences of observed mutations were tested by measuring enzyme activity and by cell and animal models. Zebrafish and mouse models were used to validate brain developmental and functional defects and to test therapeutic strategies. GOT2 encodes the mitochondrial glutamate oxaloacetate transaminase. GOT2 enzyme activity was deficient in fibroblasts with bi-allelic mutations. GOT2, a member of the malate-aspartate shuttle, plays an essential role in the intracellular NAD(H) redox balance. De novo serine biosynthesis was impaired in fibroblasts with GOT2 mutations and GOT2-knockout HEK293 cells. Correcting the highly oxidized cytosolic NAD-redox state by pyruvate supplementation restored serine biosynthesis in GOT2-deficient cells. Knockdown of got2a in zebrafish resulted in a brain developmental defect associated with seizure-like electroencephalography spikes, which could be rescued by supplying pyridoxine in embryo water. Both pyridoxine and serine synergistically rescued embryonic developmental defects in zebrafish got2a morphants. The two treated individuals reacted favorably to their treatment. Our data provide a mechanistic basis for the biochemical abnormalities in GOT2 deficiency that may also hold for other MAS defects.


Assuntos
Alelos , Ácido Aspártico/metabolismo , Encefalopatias/genética , Proteínas de Ligação a Ácido Graxo/genética , Malatos/metabolismo , Mutação , Animais , Criança , Pré-Escolar , Feminino , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Masculino , Camundongos , Sequenciamento Completo do Exoma
13.
Am J Hum Genet ; 104(6): 1116-1126, 2019 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-31104771

RESUMO

Huntington disease (HD) is caused by a CAG repeat expansion in the huntingtin (HTT) gene. Although the length of this repeat is inversely correlated with age of onset (AOO), it does not fully explain the variability in AOO. We assessed the sequence downstream of the CAG repeat in HTT [reference: (CAG)n-CAA-CAG], since variants within this region have been previously described, but no study of AOO has been performed. These analyses identified a variant that results in complete loss of interrupting (LOI) adenine nucleotides in this region [(CAG)n-CAG-CAG]. Analysis of multiple HD pedigrees showed that this LOI variant is associated with dramatically earlier AOO (average of 25 years) despite the same polyglutamine length as in individuals with the interrupting penultimate CAA codon. This LOI allele is particularly frequent in persons with reduced penetrance alleles who manifest with HD and increases the likelihood of presenting clinically with HD with a CAG of 36-39 repeats. Further, we show that the LOI variant is associated with increased somatic repeat instability, highlighting this as a significant driver of this effect. These findings indicate that the number of uninterrupted CAG repeats, which is lengthened by the LOI, is the most significant contributor to AOO of HD and is more significant than polyglutamine length, which is not altered in these individuals. In addition, we identified another variant in this region, where the CAA-CAG sequence is duplicated, which was associated with later AOO. Identification of these cis-acting modifiers have potentially important implications for genetic counselling in HD-affected families.


Assuntos
Códon/genética , Doença de Huntington/genética , Doença de Huntington/patologia , Peptídeos/genética , Expansão das Repetições de Trinucleotídeos/genética , Adolescente , Adulto , Idade de Início , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem
14.
Genes (Basel) ; 10(5)2019 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-31083486

RESUMO

Although previous research identified candidate genetic polymorphisms associated with cisplatin nephrotoxicity, varying outcome definitions potentially contributed to the variability in the effect size and direction of this relationship. We selected genetic variants that have been significantly associated with cisplatin-induced nephrotoxicity in more than one published study (SLC22A2 rs316019; ERCC1 rs11615 and rs3212986; ERCC2 rs1799793 and rs13181) and performed a replication analysis to confirm associations between these genetic polymorphisms and cisplatin nephrotoxicity using various outcome definitions. We included 282 germ cell testicular cancer patients treated with cisplatin from 2009-2014, aged >17 years recruited by the Canadian Pharmacogenomics Network for Drug Safety. Nephrotoxicity was defined using four grading tools: (1) Common Terminology Criteria for Adverse Events (CTCAE) v4.03 for acute kidney injury (AKI) or CTCAE-AKI; (2) adjusted cisplatin-induced AKI; (3) elevation of serum creatinine; and (4) reduction in the estimated glomerular filtration rate (eGFR). Significant associations were only found when using the CTCAE v4.03 definition: genotype CA of the ERCC1 rs3212986 was associated with decreased risk of cisplatin nephrotoxicity (ORadj = 0.24; 95% CI:0.08-0.70; p = 0.009) compared to genotype CC. In contrast, addition of allele A at SLC22A2 rs316019 was associated with increased risk (ORadj = 4.41; 95% CI:1.96-9.88; p < 0.001) while genotype AC was associated with a higher risk of cisplatin nephrotoxicity (ORadj = 5.06; 95% CI:1.69-15.16; p = 0.004) compared to genotype CC. Our study showed that different case definitions led to variability in the genetic risk ascertainment of cisplatin nephrotoxicity. Therefore, consensus on a set of clinically relevant outcome definitions that all such studies should follow is needed.


Assuntos
Lesão Renal Aguda/induzido quimicamente , Cisplatino/efeitos adversos , Proteínas de Ligação a DNA/genética , Endonucleases/genética , Transportador 2 de Cátion Orgânico/genética , Neoplasias Testiculares/tratamento farmacológico , Neoplasias Testiculares/genética , Proteína Grupo D do Xeroderma Pigmentoso/genética , Lesão Renal Aguda/genética , Adulto , Biomarcadores Farmacológicos , Creatinina/sangue , Proteínas de Ligação a DNA/metabolismo , Endonucleases/metabolismo , Frequência do Gene , Taxa de Filtração Glomerular/efeitos dos fármacos , Humanos , Rim/efeitos dos fármacos , Rim/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Neoplasias Embrionárias de Células Germinativas/genética , Neoplasias Embrionárias de Células Germinativas/metabolismo , Transportador 2 de Cátion Orgânico/metabolismo , Farmacogenética , Polimorfismo Genético , Estudos Retrospectivos , Neoplasias Testiculares/metabolismo , Proteína Grupo D do Xeroderma Pigmentoso/metabolismo
15.
N Engl J Med ; 380(15): 1433-1441, 2019 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-30970188

RESUMO

We report an inborn error of metabolism caused by an expansion of a GCA-repeat tract in the 5' untranslated region of the gene encoding glutaminase (GLS) that was identified through detailed clinical and biochemical phenotyping, combined with whole-genome sequencing. The expansion was observed in three unrelated patients who presented with an early-onset delay in overall development, progressive ataxia, and elevated levels of glutamine. In addition to ataxia, one patient also showed cerebellar atrophy. The expansion was associated with a relative deficiency of GLS messenger RNA transcribed from the expanded allele, which probably resulted from repeat-mediated chromatin changes upstream of the GLS repeat. Our discovery underscores the importance of careful examination of regions of the genome that are typically excluded from or poorly captured by exome sequencing.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos/genética , Ataxia/genética , Deficiências do Desenvolvimento/genética , Glutaminase/deficiência , Glutaminase/genética , Glutamina/metabolismo , Repetições de Microssatélites , Mutação , Atrofia/genética , Cerebelo/patologia , Pré-Escolar , Feminino , Genótipo , Glutamina/análise , Humanos , Masculino , Fenótipo , Reação em Cadeia da Polimerase , Sequenciamento Completo do Genoma
16.
Clin Pharmacol Ther ; 106(2): 350-359, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31012503

RESUMO

Cisplatin is a highly effective chemotherapeutic. Unfortunately, its use is limited by cisplatin-induced ototoxicity (CIO). Substantial research has been performed to uncover the genetic variants associated with CIO; however, there has been a lack of consistency in the results that have been reported. This paper aims to provide an overview of the current state of CIO genomics research, delving into the shortcomings of past research, and providing recommendations for future avenues of study.


Assuntos
Cisplatino/farmacologia , Ototoxicidade , Farmacogenética , Antineoplásicos/farmacologia , Humanos , Ototoxicidade/etiologia , Ototoxicidade/genética
17.
Arthritis Rheumatol ; 71(10): 1747-1755, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31008556

RESUMO

OBJECTIVE: Individuals with deficiency of adenosine deaminase 2 (DADA2), a recently recognized autosomal recessive disease, present with various systemic vascular and inflammatory manifestations, often with young age at disease onset or with early onset of recurrent strokes. Their clinical features and histologic findings overlap with those of childhood-onset polyarteritis nodosa (PAN), a primary "idiopathic" systemic vasculitis. Despite similar clinical presentation, individuals with DADA2 may respond better to biologic therapy than to traditional immunosuppression. The aim of this study was to screen an international registry of children with systemic primary vasculitis for variants in ADA2. METHODS: The coding exons of ADA2 were sequenced in 60 children and adolescents with a diagnosis of PAN, cutaneous PAN, or unclassifiable vasculitis (UCV), any chronic vasculitis with onset at age 5 years or younger, or history of stroke. The functional consequences of the identified variants were assessed by ADA2 enzyme assay and immunoblotting. RESULTS: Nine children with DADA2 (5 with PAN, 3 with UCV, and 1 with antineutrophil cytoplasmic antibody-associated vasculitis) were identified. Among them, 1 patient had no rare variants in the coding region of ADA2 and 8 had biallelic, rare variants (minor allele frequency <0.01) with a known association with DADA2 (p.Gly47Arg and p.Gly47Ala) or a novel association (p.Arg9Trp, p.Leu351Gln, and p.Ala357Thr). The clinical phenotype varied widely. CONCLUSION: These findings support previous observations indicating that DADA2 has extensive genotypic and phenotypic variability. Thus, screening ADA2 among children with vasculitic rash, UCV, PAN, or unexplained, early-onset central nervous system disease with systemic inflammation may enable an earlier diagnosis of DADA2.


Assuntos
Adenosina Desaminase/genética , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Poliarterite Nodosa/genética , Adenosina Desaminase/deficiência , Adolescente , Idade de Início , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Peptídeos e Proteínas de Sinalização Intercelular/deficiência , Masculino , Mutação , Dermatopatias Vasculares/genética , Vasculite Sistêmica/genética
18.
Cardiovasc Res ; 115(5): 922-934, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30768157

RESUMO

With 5-year survival of children with cancer exceeding 80% in developed countries, premature cardiovascular disease is now a major cause of early morbidity and mortality. In addition to the acute and chronic cardiotoxic effects of anthracyclines, related chemotherapeutics, and radiation, a growing number of new molecular targeted agents may also have detrimental effects on the cardiovascular system. Survivors of childhood cancer also may have earlier development of conventional cardiovascular risk factors such as hypertension, dyslipidaemia, and diabetes, which further increase their risk of serious cardiovascular disease. This review will examine the epidemiology of acute and chronic cardiotoxicity relevant to paediatric cancer patients, including genetic risk factors. We will also provide an overview of current screening recommendations, including the evidence regarding both imaging (e.g. echocardiography and magnetic resonance imaging) and blood-based biomarkers. Various primary and secondary prevention strategies will also be discussed, primarily in relation to anthracycline-related cardiomyopathy. Finally, we review the available evidence related to the management of systolic and diastolic dysfunction in paediatric cancer patients and childhood cancer survivors.


Assuntos
Antineoplásicos/efeitos adversos , Sobreviventes de Câncer , Cardiologia , Cardiopatias , Oncologia , Neoplasias/terapia , Pediatria , Lesões por Radiação , Idade de Início , Animais , Cardiotoxicidade , Cardiopatias/induzido quimicamente , Cardiopatias/diagnóstico , Cardiopatias/epidemiologia , Cardiopatias/prevenção & controle , Humanos , Neoplasias/diagnóstico , Neoplasias/epidemiologia , Prevenção Primária , Lesões por Radiação/induzido quimicamente , Lesões por Radiação/diagnóstico , Lesões por Radiação/epidemiologia , Lesões por Radiação/prevenção & controle , Radioterapia/efeitos adversos , Medição de Risco , Fatores de Risco , Prevenção Secundária , Fatores de Tempo
19.
EBioMedicine ; 40: 655-662, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30709768

RESUMO

BACKGROUND: Behaviour problems are prevalent among children born very preterm (≤ 32 weeks gestation), and have been associated with morphine exposure. Morphine accumulation in the brain is determined by genetic variations related to morphine biotransformation. The objective of the study was to investigate whether morphine-biotransformation genotypes contribute to individual differences in long-term effects of morphine on behaviour at 18 months corrected age (CA). METHODS: 198 children born very preterm (24-32 weeks gestation) were followed from birth and seen at 18 months CA. Relationships between child behavior (Internalizing, Externalizing on the Child Behavior Checklist), morphine exposure, neonatal clinical variables, and morphine biotransformation gene variants in ABCB1, UGT1A9, UGT 2B7*2, ABCC2, ABCC3, SLCO1B1, CYP3A4, COMT were examined. FINDINGS: Neonatal clinical predictors and genotypes accounted for 39% of the overall variance in behaviour. In children with the minor allele of UGT1A9 rs17863783 (marker of UGT1A6*4, UDP-glucuronosyltransferase), greater morphine exposure (p = ·0011) was associated with more Internalizing behaviour. More Externalizing behaviour was predicted by greater morphine exposure in children with the COMT rs4680 Met/Met genotype (p = ·0006). INTERPRETATION: Genetic variations that affect relative accumulation of morphine in the brain, together with neonatal clinical factors, are differentially related to anxiety and depressive symptoms (internalizing) and to acting out (externalizing) behaviours at 18 months CA in children born very preterm. FUND: NIH/NICHD HD039783 (REG); CIHR MOP86489 (REG), MOP68898 (SPM), MOP79262 (SPM, REG).


Assuntos
Transtornos do Comportamento Infantil/etiologia , Transtornos do Comportamento Infantil/psicologia , Inativação Metabólica/genética , Lactente Extremamente Prematuro/psicologia , Morfina/metabolismo , Fatores Etários , Alelos , Transtornos do Comportamento Infantil/diagnóstico , Suscetibilidade a Doenças , Feminino , Estudos de Associação Genética , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Redes e Vias Metabólicas/genética , Morfina/administração & dosagem , Prognóstico , Psicometria/métodos
20.
Brain ; 142(3): 542-559, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30668673

RESUMO

Biallelic pathogenic variants in PLPBP (formerly called PROSC) have recently been shown to cause a novel form of vitamin B6-dependent epilepsy, the pathophysiological basis of which is poorly understood. When left untreated, the disease can progress to status epilepticus and death in infancy. Here we present 12 previously undescribed patients and six novel pathogenic variants in PLPBP. Suspected clinical diagnoses prior to identification of PLPBP variants included mitochondrial encephalopathy (two patients), folinic acid-responsive epilepsy (one patient) and a movement disorder compatible with AADC deficiency (one patient). The encoded protein, PLPHP is believed to be crucial for B6 homeostasis. We modelled the pathogenicity of the variants and developed a clinical severity scoring system. The most severe phenotypes were associated with variants leading to loss of function of PLPBP or significantly affecting protein stability/PLP-binding. To explore the pathophysiology of this disease further, we developed the first zebrafish model of PLPHP deficiency using CRISPR/Cas9. Our model recapitulates the disease, with plpbp-/- larvae showing behavioural, biochemical, and electrophysiological signs of seizure activity by 10 days post-fertilization and early death by 16 days post-fertilization. Treatment with pyridoxine significantly improved the epileptic phenotype and extended lifespan in plpbp-/- animals. Larvae had disruptions in amino acid metabolism as well as GABA and catecholamine biosynthesis, indicating impairment of PLP-dependent enzymatic activities. Using mass spectrometry, we observed significant B6 vitamer level changes in plpbp-/- zebrafish, patient fibroblasts and PLPHP-deficient HEK293 cells. Additional studies in human cells and yeast provide the first empirical evidence that PLPHP is localized in mitochondria and may play a role in mitochondrial metabolism. These models provide new insights into disease mechanisms and can serve as a platform for drug discovery.


Assuntos
Epilepsia/etiologia , Proteínas/genética , Proteínas/metabolismo , Animais , Modelos Animais de Doenças , Epilepsia/fisiopatologia , Feminino , Células HEK293 , Humanos , Masculino , Fenótipo , Fosfato de Piridoxal/uso terapêutico , Piridoxina/deficiência , Vitamina B 6/metabolismo , Deficiência de Vitamina B 6/genética , Deficiência de Vitamina B 6/metabolismo , Peixe-Zebra
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