Simvastatin reduces cell proliferation and migration and triggers apoptosis in ATC cells. Incubation of ATC cells, SW1736 and 8305C, with simvastatin produces cell proliferation inhibition via inactivation of RhoA/Rac1 small GTPase protein, reduction of protein levels of CCND1, pp-Rb and E2F1, and increases of protein levels of p21cip and p27kip. Simvastatin causes cell migration inhibition via repression of Cyr61 expression. In addition, simvastatin induces apoptosis via caspase 3 and PARP activation. gg-Rac1-GTP, geranylgeranylated-Rac1-GTP; gg-RhoA-GTP, geranylgeranylated-RhoA-GTP; pp-Rb, hyperphosphorylated-Rb.