FAS and cancer: As for FAS, several FASN inhibitors have been investigated in vitro and xenograft studies and preliminary results show them to have both a killing tumor direct effect and a sensitizing effect to other cancer common therapies, e.g., 5-FU and trastuzumab (Pizer et al., 1998; Kridel et al., 2004; Vázquez et al., 2008).