Since the small GTPases of Ras and Rho families have to be prenylated to play an essential role in carcinoma cell invasion (Oxford and Theodorescu, 2003), we attempted to assess if the anti-invasive action of ZOL could be related to Ras and/or RhoA inactivation, following the decreased formation of FPP and GGPP, respectively. This evidence concerns the gene RHO and carcinoma.