Evolution and clinical impact of co-occurring genetic alterations in advanced-stage EGFR-mutant lung cancers
A partir de 1 122 échantillons sanguins prélevés sur des patients atteints d'un cancer du poumon EGFR+ et à partir de 7 échantillons tumoraux prélevés au cours de l'évolution de la maladie sur un patient complémentaire, cette étude identifie la présence simultanée d'anomalies génomiques chez la plupart des patients atteints d'un cancer de stade avancé et, en particulier, des anomalies dans les gènes CTNNB1 et PIK3CA favorisant le processus métastatique ou la réponse thérapeutique
A widespread approach to modern cancer therapy is to identify a single oncogenic driver gene and target its mutant-protein product (for example, EGFR-inhibitor treatment in EGFR-mutant lung cancers). However, genetically driven resistance to targeted therapy limits patient survival. Through genomic analysis of 1,122 EGFR-mutant lung cancer cell-free DNA samples and whole-exome analysis of seven longitudinally collected tumor samples from a patient with EGFR-mutant lung cancer, we identified critical co-occurring oncogenic events present in most advanced-stage EGFR-mutant lung cancers. We defined new pathways limiting EGFR-inhibitor response, including WNT/
β-catenin alterations and cell-cycle-gene (CDK4 and CDK6) mutations. Tumor genomic complexity increases with EGFR-inhibitor treatment, and co-occurring alterations in CTNNB1 and PIK3CA exhibit nonredundant functions that cooperatively promote tumor metastasis or limit EGFR-inhibitor response. This study calls for revisiting the prevailing single-gene driver-oncogene view and links clinical outcomes to co-occurring genetic alterations in patients with advanced-stage EGFR-mutant lung cancer.
Nature Genetics 2017