Human GTSE-1 regulates p21(CIP1/WAF1) stability conferring resistance to paclitaxel treatment.

p21(CIP1/WAF1) belongs to the CIP/KIP family of Cdk inhibitors, and its expression is tightly controlled during the cell cycle, mainly by transcriptional and post-translational mechanisms. Fine regulation of p21(CIP1/WAF1) levels is critical for cell cycle control and for cellular response to stress. In the present work, we describe a novel mechanism to modulate p21(CIP1/WAF1) levels mediated by the human GTSE-1 (G(2) and S phase-expressed-1) protein.