DFU, [5,5-dimethyl-3-(3-fluorophenyl)-4-(4-methylsulphonyl)phenyl-2(5H)-furanone], a selective COX-2 inhibitor was found to significantly reduce tumour growth in mice injected with MCF-7 cells and also inhibited growth when MCF-7 cells were cultured for a long period at high drug concentrations [6]. This evidence concerns the gene PTGS2 and neoplasm.