Background: Fatty acid synthase (FASN) is highly upregulated in human prostate carcinomas. Inhibition of FASN could arrest cell cycle and trigger apoptosis rapidly, implying the reliance of cancer cell survival on FASN. However, little is known about the effect of C75, a FASN inhibitor, and siFASN (that is, small interfering RNA targeted at FASN) on prostate cancer in living subjects.
Methods: We used C75 and siFASN to mediate the endogenous fatty acid metabolism in LNCaP human prostate cancer cells stably expressing herpes simplex virus type 1 thymidine kinase (HSV1-tk) and luciferase (luc) reporter genes, and assessed the effect of FASN blockade with different schedules of administration on tumor growth using noninvasive molecular imaging.
Results: FASN blockade exhibited the proliferative inhibition and induced G1-phase cell cycle arrest of LNCaP cells. For in vivo studies, the tumor growth inhibition by C75 (total 120 mgkg(-1); 30 mgkg(-1) once a week or 15 mgkg(-1) twice a week for 4 weeks) and siFASN (1.4 mgkg(-1) every alternate day up to 16 days) treatments were 80% and 70%, respectively, compared with that of the control.
Conclusion: The results suggest that C75 may be superior to siFASN in anticancer effect on prostate cancer.