구강암 KB 세포에서 5'-nitro-indirubinoxime에 의한 세포주기 억제기전

Abstract

5'-Nitro-Indirubinoxime (5'-NIO) is known to have anti-tumor effect in human cancer cells. The author finds that low concentrations of 5'-NIO irreversibly inhibits the proliferation of human KB oral squamous carcinoma cells and induces the inhibition of G1/S phase regulatory proteins. 5'-NIO-mediated G1/S specific cyclin-dependent kinases (CDKs) are mediated by two different mechanisms. First, 5'-NIO inhibits CDK4 with affecting significantly cyclin D1/D3 and p16INK4A. Second, 5'-NIO inhibits CDK2 by induction of the CDKs inhibitor, p21waf1. 5'-NIO-induced cell cycle arrest may induce apoptosis of human KB oral squamous carcinoma cells through mitochondria-dependent activation of caspase cascade. These observations together suggest that 5'-NIO may have a possible therapeutic potential to oral cancer.