Effect of v-erbA on RA-responsive genes in AML12 hepatocytes. Mus musculus

The v-erbA oncogene belongs to a superfamily of transcription factors called nuclear receptors, which includes the retinoic acid receptors (RARs) responsible for mediating the effects of retinoic acid (RA). Nuclear receptors bind to specific DNA sequences in the promoter region of target genes and v-erbA is known to exert a dominant negative effect on the activity of the RARs. The repressor activity of v-erbA has been linked to the development of hepatocellular carcinoma (HCC) in a mouse model. We have used microarray analysis to identify genes differentially expressed in hepatocytes in culture (AML12 cells) stably transfected with v-erbA and exposed to RA. We have found that v-erbA can affect expression of RA-responsive genes. We have also identified a number of v-erbA-responsive genes that are known to be involved in carcinogenesis and which may play a role in the development of HCC. Overall design: AML12 control cells and v-erbA-transfected AML12 cells were exposed to 1 µM RA for 3h or 24h. Using microarray analysis, we compared gene expression in the presence and absence of v-erbA and identified RA-regulated genes differentially expressed in the presence of v-erbA.