By using 3D immunofluorescence whole-mount analysis, PDOs displayed disorganized epithelial polarity (EpCAM and F-actin staining respectively, Fig. 1c, first row), random distribution of cell proliferation (Ki67, Fig. 1c, first row), displaced localization of enterocytes (FABP1, Fig. 1c, second row) and presence of cytokeratin 20 positive cells (KRT20, Fig. 1c, third and fourth rows), recapitulating the common dysplastic features of human CRC. Here, FABP1 is linked to colorectal carcinoma.