Based on the studies of PPAR-α, PPAR-γ, G0S2, and ATGL in tumors, we speculate that under the induction of hypoxia in the tumor microenvironment, cancer cells increase the expression of PPAR-α and PPAR-γ, which in turn promote the expression of their target genes G0S2, to avoid the occurrence of required FAO pathway. This evidence concerns the gene PPARA and cancer.