Objective: α-fetoprotein (AFP) expression is activated during the embryonic stage or hepatocellular carcinogenesis, so it is presumed that AFP is a key endogenous molecule to promote cell proliferation or differentiation. We carried out gene screening in an unknown family with hyper-alpha-fetoproteinemia and some sporadic menopausal women, and discussed the relationship between AFP expression and liver cirrhosis.
Methods: Peripheral blood samples from family members, patients with malignant liver tumors, and normal controls were collected. Full-length sequence of AFP was amplified and directly sequenced, and compared with normal controls. HNF-1α and HNF-1β in plasma levels of family members, patients with liver cancer, newborns, pregnant women, and normal subjects were detected by ELISA, and the relationship between HNF-1 and AFP mutation or high expression was evaluated.
Results: There was a mutation in AFP promoter region at c.-200 C>T, which was located at the binding site of AFP hepatocyte nuclear factor 1 (HNF-1). AFP was higher than 4000 ng/L in all members carrying the mutation, but liver cancer was excluded in the family with hyper-alpha-fetoprotein. However, cirrhosis occurred in post-menopausal women. The cases reviewed showed that unknown hyper-alpha-fetoprotein was closely related to HNF-1 binding point of AFP in post-menopausal women with cirrhosis (7/11), while the plasma levels of HNF-1α and HNF-1β were not significantly different.
Conclusion: The mutation of the HNF-1 binding point of AFP may lead to an abnormal high expression of AFP by altering the binding of HNF transcription factors, which is closely related to cirrhosis in menopausal women.
Keywords: Alpha fetoprotein gene mutation; HNF-1; cirrhosis; post-menopausal women; serum alpha-fetoprotein.