NORE1B is a putative tumor suppressor in hepatocarcinogenesis and may act via RASSF1A.

Recently, we found epigenetic silencing of the Ras effector genes NORE1B and/or RASSF1A in 97% of the hepatocellular carcinoma (HCC) investigated. This is strong evidence that the two genes are of major significance in hepatocarcinogenesis. Although RASSF1A serves as a tumor suppressor gene, the functions of NORE1B are largely unknown.

Deregulation of the activin/follistatin system in hepatocarcinogenesis.

Background/aims: Activins A and E negatively regulate hepatic cell number by inhibiting cell replication and inducing apoptosis. Follistatin and follistatin-like 3 bind activins and antagonise their biological activities. Aim of our study was to investigate, whether activins and follistatins may play a role in hepatocarcinogenesis.

NORE1B, a candidate tumor suppressor, is epigenetically silenced in human hepatocellular carcinoma.

Background/aims: In human hepatocellular carcinoma (HCC) the ras-proto-oncogene is rarely mutated. We therefore studied the possible inactivation of the putative tumor-suppressors and ras-associating proteins, NORE1A, NORE1B, and RASSF1A in HCCs by mutation or epigenetic gene silencing through promoter-CpG hypermethylation.

Methods: SSCP-analyses, sequencing, and methylation-specific PCR were performed in 28 fibrotic/cirrhotic livers and 40 HCCs.