PTGS2 and neoplasm: Multiple studies have shown increased expression of COX2 in prostate tumours (Gupta et al, 2000; Kirschenbaum et al, 2000; Tanji et al, 2000; Yoshimura et al, 2000; Uotila et al, 2001), although one study reported overexpression not in tumour tissue but rather in proliferative inflammatory atrophy, a putative precursor lesion of prostate cancer (Zha et al, 2001).