KRT8 and ductal breast carcinoma in situ: The expression of laminin α4 chain in normal breast and DCIS was detected in the BMs of cytokeratin-8/18-positive epithelial cells of ductal and lobular structures (weak to negative in DCIS), as well as in BMs of factor-8-positive blood vessels (Table 2; Fig. 1a, panels E and F; Fig. 1b, panels Q and R).