Figure 2.

A. Neoplastic glands with intraglandular mucin. Note the pore formation, putting the mucin produced by the tumor cells in direct contact with the extracellular matrix (rectal adenocarcinoma; MNF 116 immunostain, 100×). B. Neoplastic gland with pore formation at the invading edge showing overexpression of laminin 5-2, particularly in the neoplastic cells surrounding the pore (colonic adenocarcinoma; laminin 5-2 immunostain, 200×). C. Colonic adenocarcinoma with a dilated neoplastic gland at the invading tumor edge. Note the absence of Ki67 expression in the flat tumor cells (clone MIB 1 immunostain, 200×). D. The same gland as in panel C showing p53 expression in all cells, including the flat tumor cells at the invading tumor edge (immunostain for P53, 200×).