RAP1A and cancer: As a result of the inhibition of FPP synthase, ZOL prevents the prenylation of small G-proteins (e.g., Ras, Rho and Rap1A), which are essential for cancer cell adhesion, migration and invasion, as it induces the intracellular accumulation of the ATP analogue isopentenyl pyrophosphate (IPP) in tumor cells3.