Alpha-fetoprotein (AFP) is a 65 kDa glycoprotein found in the mammalian fetal liver, yolk sac, and GI tract. In normal adult cells, p53 binds to the repressor region of the AFP gene, thereby blocking transcription. Mutations in both p53 and beta-catenin are associated with aberrant expression of AFP. Research studies have shown that elevated serum AFP levels are predictive of hepatocellular carcinoma .
