RESUMO
STUDY QUESTION: Do genetic variations in the DNA damage response pathway modify the adverse effect of alkylating agents on ovarian function in female childhood cancer survivors (CCS)? SUMMARY ANSWER: Female CCS carrying a common BR serine/threonine kinase 1 (BRSK1) gene variant appear to be at 2.5-fold increased odds of reduced ovarian function after treatment with high doses of alkylating chemotherapy. WHAT IS KNOWN ALREADY: Female CCS show large inter-individual variability in the impact of DNA-damaging alkylating chemotherapy, given as treatment of childhood cancer, on adult ovarian function. Genetic variants in DNA repair genes affecting ovarian function might explain this variability. STUDY DESIGN, SIZE, DURATION: CCS for the discovery cohort were identified from the Dutch Childhood Oncology Group (DCOG) LATER VEVO-study, a multi-centre retrospective cohort study evaluating fertility, ovarian reserve and risk of premature menopause among adult female 5-year survivors of childhood cancer. Female 5-year CCS, diagnosed with cancer and treated with chemotherapy before the age of 25 years, and aged 18 years or older at time of study were enrolled in the current study. Results from the discovery Dutch DCOG-LATER VEVO cohort (n = 285) were validated in the pan-European PanCareLIFE (n = 465) and the USA-based St. Jude Lifetime Cohort (n = 391). PARTICIPANTS/MATERIALS, SETTING, METHODS: To evaluate ovarian function, anti-Müllerian hormone (AMH) levels were assessed in both the discovery cohort and the replication cohorts. Using additive genetic models in linear and logistic regression, five genetic variants involved in DNA damage response were analysed in relation to cyclophosphamide equivalent dose (CED) score and their impact on ovarian function. Results were then examined using fixed-effect meta-analysis. MAIN RESULTS AND THE ROLE OF CHANCE: Meta-analysis across the three independent cohorts showed a significant interaction effect (P = 3.0 × 10-4) between rs11668344 of BRSK1 (allele frequency = 0.34) among CCS treated with high-dose alkylating agents (CED score ≥8000 mg/m2), resulting in a 2.5-fold increased odds of a reduced ovarian function (lowest AMH tertile) for CCS carrying one G allele compared to CCS without this allele (odds ratio genotype AA: 2.01 vs AG: 5.00). LIMITATIONS, REASONS FOR CAUTION: While low AMH levels can also identify poor responders in assisted reproductive technology, it needs to be emphasized that AMH remains a surrogate marker of ovarian function. WIDER IMPLICATIONS OF THE FINDINGS: Further research, validating our findings and identifying additional risk-contributing genetic variants, may enable individualized counselling regarding treatment-related risks and necessity of fertility preservation procedures in girls with cancer. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the PanCareLIFE project that has received funding from the European Union's Seventh Framework Programme for research, technological development and demonstration under grant agreement no 602030. In addition, the DCOG-LATER VEVO study was funded by the Dutch Cancer Society (Grant no. VU 2006-3622) and by the Children Cancer Free Foundation (Project no. 20) and the St Jude Lifetime cohort study by NCI U01 CA195547. The authors declare no competing interests. TRIAL REGISTRATION NUMBER: N/A.
Assuntos
Reserva Ovariana , Adolescente , Adulto , Hormônio Antimülleriano/genética , Criança , Estudos de Coortes , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Ovário , Proteínas Serina-Treonina Quinases , Estudos RetrospectivosRESUMO
BACKGROUND: Children with sickle cell anemia (SCA) have an 11% risk of stroke by the age of 18. Chronic transfusion applied in patients detected to be at risk by transcranial Doppler allows a significant reduction of stroke risk. However, chronic transfusion exposes to several adverse events, including alloimmunization and iron overload, and is not curative. Hematopoietic stem cell transplantation allows termination of the transfusion program, but its benefit has not been demonstrated. DESIGN: DREPAGREFFE (NCT01340404) is a multicenter, prospective trial enrolling SCA children younger than 15years receiving chronic transfusion due to a history of abnormal transcranial Doppler (velocities ≥200cm/s). Only those with at least one non-SCA sibling and parents accepting HLA-typing and transplantation with a genoidentical donor were eligible. Chronic transfusion was pursued in patients with no available donor, whereas others were transplanted. Comparison between the 2 arms (transfusion vs transplantation) was analyzed using both genetic randomization and propensity-score matching as a sensitivity analysis. The primary end-point was the velocity measure at 1year. Secondary endpoints were the incidence of stroke, silent cerebral infarcts and stenoses, cognitive performance in comparison with siblings, allo-immunization, iron-overload, phosphatidyl-serine, angiogenesis/hypoxia, brain injury-related factor expression, quality of life and cost. OBJECTIVES: To show that genoidentical transplantation decreases velocities significantly more than chronic transfusion in SCA children at risk of stroke. DISCUSSION: DREPAGREFFE is the first prospective study to evaluate transplantation in SCA children. It compares the outcome of cerebral vasculopathy following genoidentical transplantation versus chronic transfusion using genetic randomization and causal inference methods.
Assuntos
Anemia Falciforme/complicações , Anemia Falciforme/terapia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodos , Acidente Vascular Cerebral/etiologia , Reação Transfusional , Adolescente , Transfusão de Sangue/economia , Transfusão de Sangue/métodos , Criança , Pré-Escolar , Cognição , Feminino , Transplante de Células-Tronco Hematopoéticas/economia , Humanos , Sobrecarga de Ferro/etiologia , Masculino , Estudos Prospectivos , Qualidade de Vida , Projetos de Pesquisa , Acidente Vascular Cerebral/diagnóstico por imagem , Ultrassonografia Doppler TranscranianaRESUMO
CONTEXT: Survival of children, adolescents and young adults treated for cancer increased with improved treatments. But there is still an increased risk of second primary cancer (SPC) in the long term compared to the population of the same age, especially related to treatments. A reflection on the follow-up of this population and the prevention of SPC is an important issue. OBJECTIVES: To perform a synthesis of the available literature on SCP risk factors, related risk behaviors, occupational exposures and prevention strategies. METHODS: Literature search on PubMed from the following equation: "cancer [Tiab] AND young adult [Tiab] or teen [Tiab] or childhood [Tiab] AND prevention [Tiab] AND survivors [Mesh term]". RESULTS: Twenty-seven articles were included in this synthesis. Children, adolescents and young adults have similar risk behaviors than those of their peers regarding tobacco, diet and sun exposure; however, they have lower physical activity. There are few studies on prevention strategies focused on this population. Results of available studies remain inconclusive. No publication was found in relation to occupational exposure and risk of second cancer. CONCLUSIONS: Children, adolescents and young adults treated for cancer are a population at risk and require long-term follow-up and the implementation of effective prevention strategies tailored to this population.