Abstract 130: Resolving the spatial and cellular architecture of lung adenocarcinoma by multi-region single-cell sequencing

Lung adenocarcinoma (LUAD) is the most commonly diagnosed histological subtype of lung cancer. While earlier work has underscored genomic and immune alterations in LUAD, the roles of individual cell populations in early-stage human LUAD evolution in space remain unknown. Here, we provide a detailed cellular atlas of early-stage LUAD and its spatial ecosystem along the peripheral lung. We performed single-cell RNA sequencing of 186,916 cells including enriched epithelial fractions from five early-stage LUADs with fourteen multi-region normal lung tissues of defined spatial proximities from the primary LUADs. We show that major epithelial and immune cellular lineages, states, and transcriptomic features geospatially and progressively evolve across normal regions and with increasing LUAD proximity. Analysis of 70,030 lung epithelial cells unraveled diverse lineage trajectories, transcriptional lineage plasticity programs underlying KRAS-mutant cells, and intratumoral heterogeneity within single sites. T regulatory cell programs including multiple immune checkpoints increased in tissues with closer proximity to LUADs, in sharp contrast to signatures of CD8+ cytotoxic T cells, antigen presentation by macrophages, and inflammatory dendritic cells. We found that some spatial signatures (e.g. a B cell signature score) were increased along the pathologic spectrum of normal lung, preneoplastic lesions, and matched invasive LUADs. LUAD cell-cell communication networks were enriched with ligand-receptor interactions involving CD24, LGALS9 and TIM3 immune checkpoints, including crosstalk between CD24 antigen in LUAD epithelial cells and SIGLEC10 in myeloid subsets. CD24 was markedly increased in preneoplasias relative to normal lung and further in LUAD, and its expression was highly positively correlated with immunosuppressive phenotypes. These data provide an atlas of cellular states and phenotypes underlying early-stage LUAD evolution in space, and a scalable resource for identification of targets for early treatment. Citation Format: Ansam Sinjab, Guangchun Han, Warapen Treekitkarnmongkol, Kieko Hara, Patrick Brennan, Minghao Dang, Dapeng Hao, Ruiping Wang, Enyu Dai, Hitoshi Dejima, Jiexin Zhang, Elena Bogatenkova, Beatriz Sanchez-Espiridion, Kyle Chang, Danielle R. Little, Samer Bazzi, Linh Tran, Kostyantyn Krysan, Carmen Behrens, Dzifa Duose, Edwin R. Parra, Maria Gabriela Raso, Luisa M. Solis, Junya Fukuoka, Jianjun Zhang, Boris Sepesi, Tina Cascone, Lauren A. Byers, Don L. Gibbons, Jichao Chen, Seyed Javad Moghaddam, Edwin J. Ostrin, Daniel G. Rosen, John V. Heymach, Paul Scheet, Steven Dubinett, Ignacio I. Wistuba, Junya Fujimoto, Christopher S. Stevenson, Avrum E. Spira, Linghua Wang, Humam Kadara. Resolving the spatial and cellular architecture of lung adenocarcinoma by multi-region single-cell sequencing [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 130.