PROS1 and neoplasm: These intermediate metabolites play significant roles in prenylation of small GTP-binding signaling proteins including Ras.22 Previous studies have shown the pleiotropic effects of statins on cancer and other diseases are primarily a result of a reduction in these prenylating groups.23,24 Importantly for breast cancer, signaling pathways downstream of Ras, such as PI3K–Akt and the MAP Kinase cascade, are often implicated in tumor cell growth and suppressed in dormant tumor cells.4,25,26 Thus, we hypothesize that statins will selectively target tumor cells primed to emerge from dormancy.