Genomic and immune heterogeneity of multiple synchronous lung adenocarcinoma at different developmental stages.

Multiple synchronous lung cancers (MSLCs) constitute a unique subtype of lung cancer. To explore the genomic and immune heterogeneity across different pathological stages of MSLCs, we analyse 16 MSLCs from 8 patients using single-cell RNA-seq, single-cell TCR sequencing, and bulk whole-exome sequencing. Our investigation indicates clonally independent tumours with convergent evolution driven by shared driver mutations. However, tumours from the same individual exhibit few shared mutations, indicating independent origins. During the transition from pre-invasive to invasive adenocarcinoma, we observe a shift in T cell phenotypes characterized by increased Treg cells and exhausted CD8⁺ T cells, accompanied by diminished cytotoxicity. Additionally, invasive adenocarcinomas exhibit greater neoantigen abundance and a more diverse TCR repertoire, indicating heightened heterogeneity. In summary, despite having a common genetic background and environmental exposure, our study emphasizes the individuality of MSLCs at different stages, highlighting their unique genomic and immune characteristics. Multiple synchronous lung cancers (MSLCs) are a subtype of lung cancer. Here the authors characterise MSLCs using single cell RNA sequencing, single cell TCR sequencing and bulk whole-exome sequencing to investigate the mutations that arise in and are associated with invasive adenocarcinoma development, and immune microenvironment changes in this process. [ABSTRACT FROM AUTHOR]