RESUMO
Cholangiocarcinoma (CCA) is a heterogeneous biliary tract cancer with a poor prognosis. Approximately 30% to 50% of patients harbor actionable alterations, including FGFR2 rearrangements. Pemigatinib, a potent, selective fibroblast growth factor receptor (FGFR) FGFR1-3 inhibitor, is approved for previously treated, unresectable, locally advanced or metastatic CCA harboring FGFR2 fusions/rearrangements, as detected by a US Food and Drug Administration-approved test. The next-generation sequencing (NGS)-based FoundationOneCDx (F1CDx) was US Food and Drug Administration approved for detecting FGFR2 fusions or rearrangements. The precision and reproducibility of F1CDx in detecting FGFR2 rearrangements in CCA were examined. Analytical concordance between F1CDx and an externally validated RNA-based NGS (evNGS) test was performed. Identification of FGFR2 rearrangements in the screening population from the pivotal FIGHT-202 study (NCT02924376) was compared with F1CDx. The reproducibility and repeatability of F1CDx were 90% to 100%. Adjusted positive, negative, and overall percentage agreements were 87.1%, 99.6%, and 98.3%, respectively, between F1CDx and evNGS. Compared with evNGS, F1CDx had a positive predictive value of 96.2% and a negative predictive value of 98.5%. The positive percentage agreement, negative percentage agreement, overall percentage agreement, positive predictive value, and negative predictive value were 100% for F1CDx versus the FIbroblast Growth factor receptor inhibitor in oncology and Hematology Trial-202 (FIGHT-202) clinical trial assay. Of 6802 CCA samples interrogated, 9.2% had FGFR2 rearrangements. Cell lines expressing diverse FGFR2 fusions were sensitive to pemigatinib. F1CDx demonstrated sensitivity, reproducibility, and high concordance with clinical utility in identifying patients with FGFR2 rearrangements who may benefit from pemigatinib treatment.
Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Neoplasias dos Ductos Biliares/diagnóstico , Neoplasias dos Ductos Biliares/tratamento farmacológico , Neoplasias dos Ductos Biliares/genética , Ductos Biliares Intra-Hepáticos/metabolismo , Ductos Biliares Intra-Hepáticos/patologia , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/genética , Genômica , Humanos , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Reprodutibilidade dos TestesRESUMO
Although 24 Alzheimer's disease (AD) risk loci have been reliably identified, a large portion of the predicted heritability for AD remains unexplained. It is expected that additional loci of small effect will be identified with an increased sample size. However, the cost of a significant increase in Case-Control sample size is prohibitive. The current study tests whether exploring the genetic basis of endophenotypes, in this case based on putative blood biomarkers for AD, can accelerate the identification of susceptibility loci using modest sample sizes. Each endophenotype was used as the outcome variable in an independent GWAS. Endophenotypes were based on circulating concentrations of proteins that contributed significantly to a published blood-based predictive algorithm for AD. Endophenotypes included Monocyte Chemoattractant Protein 1 (MCP1), Vascular Cell Adhesion Molecule 1 (VCAM1), Pancreatic Polypeptide (PP), Beta2 Microglobulin (B2M), Factor VII (F7), Adiponectin (ADN) and Tenascin C (TN-C). Across the seven endophenotypes, 47 SNPs were associated with outcome with a p-value ≤1x10(-7). Each signal was further characterized with respect to known genetic loci associated with AD. Signals for several endophenotypes were observed in the vicinity of CR1, MS4A6A/MS4A4E, PICALM, CLU, and PTK2B. The strongest signal was observed in association with Factor VII levels and was located within the F7 gene. Additional signals were observed in MAP3K13, ZNF320, ATP9B and TREM1. Conditional regression analyses suggested that the SNPs contributed to variation in protein concentration independent of AD status. The identification of two putatively novel AD loci (in the Factor VII and ATP9B genes), which have not been located in previous studies despite massive sample sizes, highlights the benefits of an endophenotypic approach for resolving the genetic basis for complex diseases. The coincidence of several of the endophenotypic signals with known AD loci may point to novel genetic interactions and should be further investigated.
Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/genética , Loci Gênicos/genética , Predisposição Genética para Doença/genética , Idoso , Doença de Alzheimer/diagnóstico , Biomarcadores/sangue , Endofenótipos , Feminino , Genômica , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Análise de RegressãoRESUMO
This unit describes methods used in the analysis of mitochondrial DNA (mtDNA) for forensic and research applications. UNIT describes procedures specifically for forensic casework where the DNA from evidentiary material is often degraded or inhibited. In this unit, protocols are described for quantification of mtDNA before amplification; amplification of the entire control region from high-quality samples as well as procedures for interrogating the whole mitochondrial genome (mtGenome); quantification of mtDNA post-amplification; and, post-PCR cleanup and sequencing. The protocols for amplification were developed for high-throughput databasing applications for forensic DNA testing such as reference samples and population studies. However, these same protocols can be applied to biomedical research such as age-related disease and health disparities research.
