Dysregulation of HNF4α expression has been associated with many human diseases such as ulcerative colitis, colon cancer, maturity-onset diabetes of the young, liver cirrhosis, and hepatocellular carcinoma.
The HNF4A gene uses two separate promoters P1 and P2, with P1 products predominant in adult liver, whereas P2 products prevalent in fetal liver, pancreas, and liver/colon cancer.
In this study, we aimed to identify candidate colon cancer chemopreventive drugs based on the transcriptional activities of TCF/LEF, NF-κB and NRF2, that play important roles in the process of malignant transformation.
Thus, the HNF4α isoforms play distinct roles in colon cancer, which could be due to differential interactions with the Wnt/β-catenin/TCF4 and AP-1 pathways.
Immunohistochemical analysis of approximately 450 human colon cancer specimens (Stage III) reveals that P1-HNF4α is either lost or localized in the cytoplasm in approximately 80% of tumors, and that staining for active Src correlates with those events in a subset of samples.
Many colon cancers suffer mutations in either the adenomatous polyposis coli or beta-catenin genes that lead to stabilization of beta-catenin and activation of downstream T-cell factor (Tcf) target genes.