High Cks1 expression is associated with aggressive breast tumors and correlates with low p27Kip1 levels in some cases, although it is also an independent prognostic marker for survival, and provides predictive information in addition to that provided by p27Kip1 alone.
Cks1, a small protein whose expression is strongly associated with aggressive breast tumors, is a component of cyclin-cdk complexes, as well as the SCF(Skp2) ubiquitin ligase.