Integration of spatial transcriptomics with Cas9-based lineage tracing in a mouse model of lung adenocarcinoma reveals that rapid subclonal expansion creates hypoxic tumor interiors that drive sequential microenvironmental remodeling—characterized by immunosuppressive macrophage infiltration, fibroblast activation, and decreased cancer cell plasticity—culminating in the emergence of spatially-confined, pro-metastatic EMT subclones that maintain enhanced fibrotic programs upon dissemination to distant sites.

Tumour progression is driven by dynamic interactions between cancer cells and their surrounding microenvironment. Investigating the spatiotemporal evolution of tumours can provide crucial insights into how intrinsic changes within cancer cells and extrinsic alterations in the microenvironment cooperate to drive different stages of tumour progression. Here, we integrate high-resolution spatial transcriptomics and evolving lineage tracing technologies to elucidate how tumour expansion, plasticity, and metastasis co-evolve with microenvironmental remodelling in a Kras;p53-driven mouse model of lung adenocarcinoma. We find that rapid subclonal expansion contributes to a hypoxic, immunosuppressive, and fibrotic microenvironment that is associated with the emergence of pro-metastatic cancer cell states. Furthermore, metastases arise from spatially-confined subclones of primary tumours and remodel the distant metastatic niche into a fibrotic, collagen-rich microenvironment. Together, we present a comprehensive dataset integrating spatial assays and lineage tracing to elucidate how sequential changes in cancer cell state and microenvironmental structures cooperate to promote tumour progression.