SMAD4 and neoplasm: For quantification, H&E stains as well as IHC for Mothers against decapentaplegic homolog 4 (SMAD4) and Tumor protein 53 (p53) guided the identification of tumor regions and individual cells, which were then manually matched to corresponding regions in serial sections, while SMAD4/p53 stains were used to navigate through the sections (Supplementary Fig. 1).