ACE and hepatocellular carcinoma: Although the current tumor markers, such as AFP, AFP-L3, and DCP, play an important role in the diagnosis of HCC, they are mostly used in conjunction due to lack of specificity.[35–38] Along with the antigens of tumor cells were easily changing, anti-tumor-associated antigens (TAA) may be detected before symptoms appear in 5 years, demonstrating that the body could be an immune reaction to that abnormal auto-antigen early.