Lung cancer in never smokers (LCINS) accounts for around 25% of all lung cancers1,2 and has been associated with exposure to second-hand tobacco smoke and air pollution in observational studies3-5. Here we use data from the Sherlock-Lung study to evaluate mutagenic exposures in LCINS by examining the cancer genomes of 871 treatment-naive individuals with lung cancer who had never smoked, from 28 geographical locations. KRAS mutations were 3.8 times more common in adenocarcinomas of never smokers from North America and Europe than in those from East Asia, whereas a higher prevalence of EGFR and TP53 mutations was observed in adenocarcinomas of never smokers from East Asia. Signature SBS40a, with unknown cause6, contributed the largest proportion of single base substitutions in adenocarcinomas, and was enriched in cases with EGFR mutations. Signature SBS22a, which is associated with exposure to aristolochic acid7,8, was observed almost exclusively in patients from Taiwan. Exposure to secondhand smoke was not associated with individual driver mutations or mutational signatures. By contrast, patients from regions with high levels of air pollution were more likely to have TP53 mutations and shorter telomeres. They also exhibited an increase in most types of mutations, including a 3.9-fold increase in signature SBS4, which has previously been linked with tobacco smoking9, and a 76% increase in the clock-like10 signature SBS5. A positive dose-response effect was observed with air-pollution levels, correlating with both a decrease in telomere length and an increase in somatic mutations, mainly attributed to signatures SBS4 and SBS5. Our results elucidate the diversity of mutational processes shaping the genomic landscape of lung cancer in never smokers.

• MeSH
• adenokarcinom genetika   MeSH
• erbB receptory genetika   MeSH
• genom lidský * genetika   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mutace * genetika   MeSH
• mutageneze * genetika   MeSH
• nádorový supresorový protein p53 genetika   MeSH
• nádory plic * genetika   patologie   MeSH
• nekuřáci * MeSH
• protoonkogenní proteiny p21(ras) genetika   MeSH
• senioři MeSH
• znečištění ovzduší škodlivé účinky   MeSH
• znečištění tabákovým kouřem škodlivé účinky   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Evropa MeSH
• Názvy látek
• EGFR protein, human MeSH Prohlížeč
• erbB receptory MeSH
• KRAS protein, human MeSH Prohlížeč
• nádorový supresorový protein p53 MeSH
• protoonkogenní proteiny p21(ras) MeSH
• TP53 protein, human MeSH Prohlížeč
• znečištění tabákovým kouřem MeSH

Understanding lung cancer evolution can identify tools for intercepting its growth. In a landscape analysis of 1024 lung adenocarcinomas (LUAD) with deep whole-genome sequencing integrated with multiomic data, we identified 542 LUAD that displayed diverse clonal architecture. In this group, we observed an interplay between mobile elements, endogenous and exogenous mutational processes, distinct driver genes, and epidemiological features. Our results revealed divergent evolutionary trajectories based on tobacco smoking exposure, ancestry, and sex. LUAD from smokers showed an abundance of tobacco-related C:G>A:T driver mutations in KRAS plus short subclonal diversification. LUAD in never smokers showed early occurrence of copy number alterations and EGFR mutations associated with SBS5 and SBS40a mutational signatures. Tumors harboring EGFR mutations exhibited long latency, particularly in females of European-ancestry (EU_N). In EU_N, EGFR mutations preceded the occurrence of other driver genes, including TP53 and RBM10. Tumors from Asian never smokers showed a short clonal evolution and presented with heterogeneous repetitive patterns for the inferred mutational order. Importantly, we found that the mutational signature ID2 is a marker of a previously unrecognized mechanism for LUAD evolution. Tumors with ID2 showed short latency and high L1 retrotransposon activity linked to L1 promoter demethylation. These tumors exhibited an aggressive phenotype, characterized by increased genomic instability, elevated hypoxia scores, low burden of neoantigens, propensity to develop metastasis, and poor overall survival. Reactivated L1 retrotransposition-induced mutagenesis can contribute to the origin of the mutational signature ID2, including through the regulation of the transcriptional factor ZNF695, a member of the KZFP family. The complex nature of LUAD evolution creates both challenges and opportunities for screening and treatment plans.

• Publikační typ
• časopisecké články MeSH
• preprinty MeSH