In normal adult liver, the cytokeratin (CK) expression pattern in hepatocytes is different from that in ductal biliary cells. Intermidiate filament (IF) cytoskeleton of hepatocytes consists of only CK8 and CK18 (hepatocyte type CKs), while the bile ductal and ductular cells contain CK7 and CK19 (bile duct type CKs) hi addition to CKS and CK18. It was believed that the difference between these two types of liver cells in their CK patterns could be maintained under all pathological conditions, even after neop...