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BACKGROUND: Personalised medicine is nowadays a major objective in oncology. Molecular characterization of tumours through NGS offers the possibility to find possible therapeutic targets in a time- and cost-effective way. However, the low quality and complexity of FFPE DNA samples bring a series of disadvantages for massive parallel sequencing techniques compared to high-quality DNA samples (from blood cells, cell cultures, etc.). RESULTS: We performed several experiments to understand the behaviour of FFPE DNA samples during the construction of SureSelectQXT libraries. First, we designed a quality checkpoint for FFPE DNA samples based on the quantification of their amplification capability (qcPCR). We observed that FFPE DNA samples can be classified according to DIN value and qcPCR concentration into unusable, or low-quality (LQ) and good-quality (GQ) DNA. For GQ samples, we increased the amount of input DNA to 150 ng and the digestion time to 30 min, whereas for LQ samples, we used 50 ng of DNA as input but we decreased the digestion time to 1 min. In all cases, we increased the cycles of the pre-hyb PCR to 10 but decreased the cycles of the post-hyb PCR to 8. In addition, we confirmed that using half of the volume of reagents can be beneficial. Finally, in order to obtain better results, we designed a decision flow-chart to achieve a seeding concentration of 12-14 pM for MiSeq Reagent Kit v2. CONCLUSIONS: Our experiments allowed us to unveil the behaviour of low-quality FFPE DNA samples during the construction of SureSelectQXT libraries. Sequencing results showed that, using our modified SureSelectQXT protocol, the final percentage of usable reads for low-quality samples was increased more than three times allowing to reach median depth/million reads values of 76.35. This value is equivalent to ~ 0.9 and ~ 0.7 of the values obtained for good-quality FFPE and high-quality DNA respectively.
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Smoldering multiple myeloma (SMM) precedes multiple myeloma (MM). The risk of progression of SMM patients is not uniform, thus different progression-risk models have been developed, although they are mainly based on clinical parameters. Recently, genomic predictors of progression have been defined for untreated SMM. However, the usefulness of such markers in the context of clinical trials evaluating upfront treatment in high-risk SMM (HR SMM) has not been explored yet, precluding the identification of baseline genomic alterations leading to drug resistance. For this reason, we carried out next-generation sequencing and fluorescent in-situ hybridization studies on 57 HR and ultra-high risk (UHR) SMM patients treated in the phase II GEM-CESAR clinical trial (NCT02415413). DIS3, FAM46C, and FGFR3 mutations, as well as t(4;14) and 1q alterations, were enriched in HR SMM. TRAF3 mutations were specifically associated with UHR SMM but identified cases with improved outcomes. Importantly, novel potential predictors of treatment resistance were identified: NRAS mutations and the co-occurrence of t(4;14) plus FGFR3 mutations were associated with an increased risk of biological progression. In conclusion, we have carried out for the first time a molecular characterization of HR SMM patients treated with an intensive regimen, identifying genomic predictors of poor outcomes in this setting.
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Biomarcadores Tumorais , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos , Mutação , Mieloma Múltiplo Latente , Humanos , Masculino , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Mieloma Múltiplo Latente/genética , Biomarcadores Tumorais/genética , Pessoa de Meia-Idade , Idoso , Sequenciamento de Nucleotídeos em Larga Escala , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêuticoRESUMO
Germline/somatic BRCA-mutated ovarian carcinomas (OC) are associated to have better response with platinum-based chemotherapy and long-term prognosis than non-BRCA-associated OCs. In addition, these mutations are predictive factors to response to Poly(ADP-ribose) polymerase (PARP) inhibitors. Different positioning papers have addressed the clinical recommendations for BRCA testing in OC. This consensus guide represents a collection of technical recommendations to address the detection of BRCA1/2 mutations in the molecular diagnostic testing strategy for OC. Under the coordination of Spanish Society of Pathology (SEAP-IAP) and the Spanish Society of Human Genetics (AEGH), these recommendations have been developed by pathologists and geneticists taking into account previously published recommendations and their experience in the molecular characterization of these genes. Since the implementation of BRCA testing as a predictive factor can initiate the workflow by testing germline mutations in the blood or by testing both germline and somatic mutations in tumor tissue, distinctive features of both strategies are discussed. Additionally, the recommendations included in this paper provide some references, quality parameters, and genomic tools aimed to standardize and facilitate the clinical genomic diagnosis of OC.
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Proteína BRCA1/genética , Proteína BRCA2/genética , Carcinoma Epitelial do Ovário/genética , Detecção Precoce de Câncer , Mutação/genética , Carcinoma Epitelial do Ovário/diagnóstico , Consenso , Detecção Precoce de Câncer/métodos , Feminino , HumanosRESUMO
OBJECTIVES: The primary aim of this study was to compare the frequency of overweight and obesity in Spanish children and teenagers by using national and international standards for the body mass index (BMI). The second aim was to establish the association between criteria based on BMI and body composition. The third aim was to propose new standards of fat percentages in order to increase diagnostic accuracy in patients with excess weight. MATERIAL AND METHODS: The sample was composed of 7,228 boys and girls aged between 6 and 20 years. Anthropometric measurements were taken (height, weight and subcutaneous skinfolds), and BMI and the percentage of fat were obtained using the methods of Durnin and Womersley, Siri and Slaughter et al. To classify obesity and overweight, the national standards of Hernández et al and the international standards published by Cole et al were used. The correlation between BMI and percentage of fat was established using Spearman's method and the variability fat percentage was estimated in relation to the BMI cut-off points proposed by the International Obesity Task Force (IOTF). RESULTS AND CONCLUSIONS: Overweight and obesity were more frequent in boys than in girls and in the youngest individuals. According to national standards, between 9.6 % (6-12 years) and 9.5 % (13-20 years) of girls and between 10.62 % (13-20 years) and 12.50 % (6-12 years) of boys were overweight. According to international standards, between 4.68 % (13-20 years) and 6 % (6-12 years) of boys were obese and between 18.83 % (13-20 years) and 21.6 % (6-12 years) were overweight. The proportion of obesity in girls ranged from 2.81 % (13-20 years) to 5.9 % (6-12 years); the prevalence of overweight was 25.99 % in the group aged 6-12 years and was 14.55 % in that aged 13-20 years. The analysis carried out shows that the association between BMI and adiposity differs in normal individuals and in those with excess weight. The international standards of Cole et al tend to underestimate obesity and to overestimate overweight. Therefore, their usefulness is limited to comparative studies and their use cannot be recommended in clinical diagnosis, where it would be more effective to use of specific population standards, especially those for fat percentage.