Eight key genes, including ARNT2, PPARG, PPARD, FGF11, JUP, CDKN1A, bradykinin receptor B2 (BDKRB2) and LAMB3, overlapped from the 56 genes mentioned above, and 702 differentially expressed genes between the G3 and G1 groups and the top 50 genes negatively/positively correlated with tumor grade were obtained. The gene discussed is PPARG; the disease is neoplasm.