**3. Immunogenicity of HCC**

Tumor immunogenicity of HCC has been first demonstrated by using autologous tumor lysate and dendritic cells for the prevention of recurrence in HCC patients. Subsequently, several tumor-associated antigens (SART2, CypB, SART3, AFP p53, MRP3, and hTERT) have been identified and characterized in HCC, suggesting the development of highly effective immunotherapy [9, 10].

The modulation of immune costimulatory molecules has been also shown to play critical role in the pathogenicity of the liver. The costimulatory ligand member B7 is a crucial immune checkpoint in HCC [11]. B7-1, B7-2, B7-DC, and B7-H1 are expressed on professional antigenpresenting cells and regulate T cell activation after the binding with CD28, CTLA-4, or PD-1. B7-H3 is expressed in human HCC cells and is associated with tumor aggressiveness and postoperative recurrence [12]. Apparently, B7-H3 promotes aggression and invasion of HCC by targeting epithelial-to-mesenchymal transition via JAK2/STAT3/Slug signaling pathway [13].
