PPARA and neoplasm: Although tumors derived from MEFs deficient of PPARα were partially suppressed in WT animals (by 41%), indicating a cell-autonomous role of PPAR in tumor growth, a drastic effect in tumor suppression was observed when the host was PPARα deficient both in the case of PPARα(+/+) tumors (87% suppression) as well as PPARα(−/−) tumors (97% suppression) (Figure 1C).