Investigation of ErbB1 and ErbB2 expression for therapeutic targeting in primary liver tumours

Molecular targets are needed for primary liver tumours.

ErbB1 and ErbB2 expression was analysed in neoplastic and surrounding tissue in surgical specimens from 52 hepatocellular carcinomas and 48 intrahepatic cholangiocarcinomas, randomly chosen from cases surgically treated in this institution.

ErbB1 and ErbB2 expression were evaluated immunohistochemically, the latter by Herceptest. Gene amplification of ErbB2 was tested by chromogenic in situ hybridisation.

In normal/cirrhotic non-neoplastic tissue, the ErbB1 (but not ErbB2) antibody commonly stained normal hepatocytes and mature intrahepatic ducts. In neoplastic tissue, moderate/strong ErbB1 immunostaining occurred in 43/52 (85%) hepatocellular carcinomas and 39/48 (81%) intra-hepatic cholangiocarcinomas. With ErbB2 Herceptest, 0/52 (0%) hepatocellular carcinomas and 2/48 (4%) intra-hepatic cholangiocarcinomas had treatable scores of 2+/3+ (chromogenic in situ hybridisation confirmed gene amplification in the latter two cases only). Neither ErbB1 nor ErbB2 expression correlated with any of the main clinical-pathologic features or survival.

Although not related to prognosis, ErbB1 could be a molecular target in a large percentage of patients with hepatocellular carcinoma or intrahepatic cholangiocarcinoma. Inclusion of anti-ErbB1 drugs such as ZD 1839 and c225 (and possibly also anti-ErbB2 drugs like Trastuzumab for a small subset of patients) in clinical trials is suggested.