Single-cell RNA sequencing identifies dysregulated NOTCH3 signaling in tumor stroma of lung adenocarcinoma

ABSTRACT: Cancer immunotherapy has revolutionized the treatment of lung adenocarcinoma (LUAD); however, a significant fraction of patients fails to respond. Recent studies to understand transcriptomic determinants of immunotherapy response have pinpointed stroma-mediated resistance mechanisms. To gain a better understanding of the stromal biology at the cellular and molecular levels in LUAD, we obtained the transcriptomes of 256,379 single cells with 13,857 mesenchymal cells from 9 treatment-naïve patients. Among the mesenchymal cells, we identify subsets of FAP+PDPN+ cancer-associated fibroblasts (CAFs) and ACTA2+MCAM+ pericytes, which enrich in tumors, differentiate from lung resident fibroblasts and possess a myofibroblast phenotype. By utilizing imaging-mass cytometry, we found that both subsets are topographically adjacent to the perivascular niche and have close spatial interaction with endothelial cells (ECs). Modelling of ligand and receptor interactomes between mesenchymal and ECs identifies that NOTCH3/NOTCH signaling drives the cell-cell interaction in tumors, with pericytes and CAFs as the signal receivers and arterial and PLVAPhigh immature neovascular ECs as the signal senders. Either pharmacologically blocking NOTCH signaling or tuning down NOTCH3 level in mesenchymal cells reduced collagen production and suppressed cell invasion. By evaluating the clinical relevance of NOTCH signaling using bulk-RNA sequencing data, we demonstrate that NOTCH3 correlates with poor survival in stroma-rich patients and that a T-cell inflammation gene signature predicts survival only in low-NOTCH3 expressing patients. Our study underscores the importance of NOTCH3 in regulating tumor stroma biology and may serve as a potential target for immunotherapy combination strategies.

ORGANISM(S): Homo sapiens

PROVIDER: GSE253013 | GEO | 2024/01/31

REPOSITORIES: GEO