Tanaka et al. suggested a regulatory role of cyclooxygenase (COX)-2 in the expression of Ang-2 in HCC, since specific COX-2 inhibition attenuated Ang-2 expression, as well as inhibited tumor angiogenesis and growth in a subcutaneous syngeneic HCC mouse model. This evidence concerns the gene ANGPT2 and hepatocellular carcinoma.