Transcription of biliary glycoprotein I gene in malignant and non-malignant human liver tissues.

Biliary glycoprotein I (BGP I) is a member of carcinoembryonic antigen (CEA) gene family consisting of at least 11 related genes. The transcription of BGP I gene was analysed in malignant and non-malignant human liver tissues with a 396-bp 3'-untranslated region probe from a cDNA clone 4-13 which was newly isolated from an adult human colon cDNA library. Among 21 tissue samples from 14 patients with hepatocellular carcinoma, 16 samples were clearly shown to express a single 3.9-kb message. This message was also found in the hepatoma cell line HuH-7. When the malignant tissues were compared to the non-malignant ones for the intensity of the band, no significant difference was observed. mRNAs of CEA and non-specific cross-reacting antigen (NCA) were not detected in 5 samples which were shown to have the message of the BGP I gene. These data suggest that the human hepatocyte and its malignant transformant produce BGP I, and that this could correspond to the cross-reacting antigen previously detected in the liver.