The present invention provides anti-cancer agents comprising protein C inhibitor (PCI) or derivatives thereof as an active ingredient. The anti-cancer agents of the present invention have activities of suppressing cancer cell growth, and cancer metastasis, infiltration, and angiogenesis. Further, the present invention has shown that derivatives containing a heparin-binding domain of PCI inhibit the growth, metastasis and angiogenesis of cancer cells. Therefore, according to the present invention, PCI or derivatives thereof are useful for inhibiting the growth, metastasis and angiogenesis of cancer.
