Expression of apoptosis, proliferating cell nuclear antigen, and apoptosis‐related antigens (bcl‐2, c‐myc, Fas, Lewis and p53) in human cholangiocarcinomas and hepatocellular carcinomas

摘要

In situ expressionof apoptosis and its related antigens has rarely been evaluated in human liver tumors. Therefore, Investigation usingin situnick end‐labelling and Immunohistochemical methods of thein situexpression of apoptosis, prollferating cells, and apoptosis‐related antigens in 7 normal livers, 20 cholanglocarclnomas (CC) and 17 hepatocellular carclnomas (HCC) was done. Apoptotlc cells as determined by the nick end‐labelling method and proliferating cell nuclear antigen‐positive cells were present in all specimens, and the percentage of them was significantly higher in CC than In HCC. Bcl‐2 protein was present only in one CC e+nd one HCC, but was occasionally noted in bile ducts in non‐cancerous livers. C‐myc and Fas antigens were not found in any of the cases. Lewisyantigen was expressed In 8 CC, but was absent in the other cases although bile ducts In non‐cancerous livers frequently expressed Lewisy. p53 protein was present in 8 CC, but was absent in the other cases. Serial section observation showed that apoptotic cancer cells ware consistently negative for proliferating cell nuclear antigen; bcl‐2‐positive cells did not show apoptosis; p53‐positive cancer cells showed apoptosis. Some Lewisypositive cancer cells showed apoptosis, while others did not. These data suggest that apoptosis and cell proliferation are lnvolved in CC and HCC, and their degree is more severe in CC than In HCC. p53 protein (stimulative) may regulate apoptosis in some cases, whereas c‐myc, Fas and Lewisyare not relatad to apoptosb In CC and HCCin vivo. Many other factors may regulate apoptos