RESUMEN
Integrated genomic analysis of 456 pancreatic ductal adenocarcinomas identified 32 recurrently mutated genes that aggregate into 10 pathways: KRAS, TGF-ß, WNT, NOTCH, ROBO/SLIT signalling, G1/S transition, SWI-SNF, chromatin modification, DNA repair and RNA processing. Expression analysis defined 4 subtypes: (1) squamous; (2) pancreatic progenitor; (3) immunogenic; and (4) aberrantly differentiated endocrine exocrine (ADEX) that correlate with histopathological characteristics. Squamous tumours are enriched for TP53 and KDM6A mutations, upregulation of the TP63∆N transcriptional network, hypermethylation of pancreatic endodermal cell-fate determining genes and have a poor prognosis. Pancreatic progenitor tumours preferentially express genes involved in early pancreatic development (FOXA2/3, PDX1 and MNX1). ADEX tumours displayed upregulation of genes that regulate networks involved in KRAS activation, exocrine (NR5A2 and RBPJL), and endocrine differentiation (NEUROD1 and NKX2-2). Immunogenic tumours contained upregulated immune networks including pathways involved in acquired immune suppression. These data infer differences in the molecular evolution of pancreatic cancer subtypes and identify opportunities for therapeutic development.
Asunto(s)
Genes Relacionados con las Neoplasias/genética , Genoma Humano/genética , Genómica , Mutación/genética , Neoplasias Pancreáticas/clasificación , Neoplasias Pancreáticas/genética , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Carcinoma Ductal Pancreático/clasificación , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/inmunología , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patología , Línea Celular Tumoral , Metilación de ADN , Proteínas de Unión al ADN/genética , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Factor Nuclear 3-beta del Hepatocito/genética , Factor Nuclear 3-gamma del Hepatocito/genética , Histona Demetilasas/genética , Proteína Homeobox Nkx-2.2 , Proteínas de Homeodominio/genética , Humanos , Ratones , Proteínas Nucleares/genética , Neoplasias Pancreáticas/inmunología , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Pronóstico , Receptores Citoplasmáticos y Nucleares/genética , Análisis de Supervivencia , Transactivadores/genética , Factores de Transcripción/genética , Transcripción Genética , Transcriptoma , Proteína p53 Supresora de Tumor/genética , Proteínas Supresoras de Tumor/genética , Proteínas de Pez CebraRESUMEN
Pancreatic cancer remains one of the most lethal of malignancies and a major health burden. We performed whole-genome sequencing and copy number variation (CNV) analysis of 100 pancreatic ductal adenocarcinomas (PDACs). Chromosomal rearrangements leading to gene disruption were prevalent, affecting genes known to be important in pancreatic cancer (TP53, SMAD4, CDKN2A, ARID1A and ROBO2) and new candidate drivers of pancreatic carcinogenesis (KDM6A and PREX2). Patterns of structural variation (variation in chromosomal structure) classified PDACs into 4 subtypes with potential clinical utility: the subtypes were termed stable, locally rearranged, scattered and unstable. A significant proportion harboured focal amplifications, many of which contained druggable oncogenes (ERBB2, MET, FGFR1, CDK6, PIK3R3 and PIK3CA), but at low individual patient prevalence. Genomic instability co-segregated with inactivation of DNA maintenance genes (BRCA1, BRCA2 or PALB2) and a mutational signature of DNA damage repair deficiency. Of 8 patients who received platinum therapy, 4 of 5 individuals with these measures of defective DNA maintenance responded.