As presented in Table III, there were significant differences for the intense positive rate (χ2=16.4, 13.8, and 29.7, respectively) and total positive rate (χ2=33.6, 11.2, and 29.0, respectively) of PPAR-γ, TSP-1 and TGF-β, between low- and high-grade gliomas. This evidence concerns the gene PPARG and central nervous system cancer.