Peripheral benzodiazepine receptors in hepatocellular carcinoma.

Peripheral benzodiazepine receptor system (PBRs) triggers intracellular metabolic events and has been associated with cell proliferation. Its endogenous ligand, the diazepam binding inhibitor (DBI), contributes to steroidogenesis by promoting cholesterol delivery to the inner mitochondrial membrane. Since an increased number of PBRs have been found in several tumour tissues and cell lines, the present study was performed in order to verify if the expression of PBRs and DBI were altered in liver tumours. Using immunocytochemestry and in situ hybridisation we studied PBRs end DBI expression in 6 human tumours sited in the liver, in 1 liver hyperplasia, in 1 cirrhotic nodular regeneration, in 1 intestinal adenocarcionma and in correspondent surrounding non tumoral liver tissue (NTLT). Immunocytochemical study and in situ hybridisation revealed that PBRs and DBI were prominently expressed in neoplastic tissues than in NTLT and that they were colocalised in the same cells.