A fibroblast-centric network drives cold fibrosis in the tumor microenvironment of lung squamous cell carcinoma
The tumor microenvironment (TME) of chronic inflammation-associated cancers (CIACs) is shaped by cycles of injury and maladaptive repair, yet the principles organizing fibrotic stroma in these tumors remain unclear. Here, we applied the concept of hot versus cold fibrosis, originally credentialed in non-cancerous fibrosis of the heart and kidney, to lung squamous cell carcinoma (LUSC), a prototypical CIAC. We generated single-cell RNA-sequencing profiles from matched primary LUSC tumors and adjacent histologically normal lung tissue collected at surgical resection from 16 treatment-naive patients. After quality control, the dataset comprises 197,232 cells (90,556 tumor-derived and 106,676 adjacent-normal) spanning major epithelial, stromal, endothelial, and immune compartments, including cancer-associated fibroblasts (CAFs), macrophages, T cells, B cells, and additional innate lineages. Comparative analysis of matched tumor versus adjacent normal tissues reveals a CAF-enriched, macrophage-depleted stromal architecture consistent with a cold fibrosis TME and identifies CAF transcriptional reprogramming toward myofibroblast and stress-response states. Ligand-receptor network inference highlights CAF-centered signaling, including autocrine growth factor loops (e.g., TIMP1, INHBA, TGFB1, GMFB) and paracrine interactions with epithelial and immune populations. Overall design: single-cell RNA-seq of paired LUSC tumor and adjacent-normal lung tissue from 16 untreated patients to map cellular composition and stromal signaling programs associated with cold-fibrotic tumor architecture.