The article discusses the role of argyrin A to p27Kip-1 in response to proteasome inhibition. It offers an overview of proteasome as one of two major degradation systems in the cell, how cellular processes involving p27 provide antitumor functions and the more potent capability of argyrin A in inhibiting apoptosis. Moreover, it cites that Athe protein build-up problems of these proteasome inhibitors.