The immunosuppression role of alpha-fetoprotein in human hepatocellular carcinoma

Human hepatocellular carcinoma (HCC) is the third most common cause of cancer-related death. Alpha-fetoprotein (AFP) is perhaps the best-defined tumor marker for HCC, and as such, it is widely used in clinical settings as an adjuvant diagnostic and prognostic tool. Up to 70% of HCC cases exhibit elevated serum level of AFP, but its pathophysiological functions in HCC are poorly defined. It is now known that AFP is not just a fetal form of carrier protein and a tumor marker, it is also critically involved in the regulation of several important cellular functions, such as cell growth, differentiation, apoptosis, angiogenesis, and immune regulation. In this mini-review, we summarize the recent development of AFP in hepatocellular carcinoma.