Hepatocellular carcinoma: is there a potential for chemoprevention using cyclooxygenase-2 inhibitors?

Inhibitors of cyclooxygenase-2 (COX-2) have proapoptotic and antiangiogenic effects on malignant tumors and inhibit their invasion to surrounding tissues. These properties are derived from COX-dependent and/or COX-independent signaling via peroxisome proliferator-activated receptor gamma. Although the role of COX-2 involvement in human hepatocarcinogenesis has not been determined yet, selective COX-2 inhibitors with COX-independent properties may potentially suppress hepatocarcinogenesis. This hypothesis should be confirmed in in vivo studies using animal models. These studies may provide insights into any application of the COX-2 inhibitor for primary and/or secondary chemoprevention.