ANG and hepatocellular carcinoma: As Ang-1 and Ang-2 compete for interaction with the same receptor, and Ang-2 expression is upregulated in human HCC tissue, Mitsuhashi et al. suggested that the quantitative balance between Ang-1 and Ang-2 expression might be a better way to assess the role of Ang signaling on HCC angiogenesis and progression.