COL1A1 and neoplasm: Clustering of spatial gene expression data identified prominent niches with PDAC sections; i) CAF-rich stroma, located at the tumor-stromal interface with high fibroblast markers (ACTA2, FAP, COL1A1); ii) Hypoxic tumor cores, often proximal to necrotic regions and marked by upregulation of hypoxia-inducible genes like CA9, and VEGFA; and iii) Immune suppressive margins, characterized by accumulation of macrophages and regulatory T-cell signals (e.g., high CD163, TGFB1, low cytotoxic T-cell presence).