Additional studies showed thatthe tumor-enhancing effect of the selective COX-2 inhibitor in COX-2 negativeor weakly COX-2 expressing human pancreatic cancers was abolished by GW9662, anirreversible pharmacological PPAR-γ antagonist, suggesting biologically importantinteractions between the COX-2 inhibitor and PPAR-γ [42]. This evidence concerns the gene PPARG and neoplasm.