- Heterogeneity: Notable intertumor variation.Tumorigenicity: Cancer stem cells as primary drivers.- Pathways: Enrichment in IL6/JAK/STAT3, PI3K/AKT/MTOR, TGF-β signaling.Gene expression: High expression during PDAC (EPCAM, KRT19, MUC1, CEACAM6).- Key Drivers: VEGF/VEGFR, HIF2, and P53 signaling pathway, MMP7, TSPAN8, MSLN, LAMC2, KLK6, and LY6D.- Genes Involved in Tumor Progression: MUC1 and CEACAM6. The gene discussed is PIK3CA; the disease is cancer.