“…Although the implications of COX-2 in cell proliferation, cell transformation, and carcinogenesis have been evidential in most of the previous studies (4,20), there is still some evidence showing that COX is not involved in biological effects in some systems (38,39). For example, Lu et al (38) has reported that overexpressing human cDNA of COX-2 in human breast epithelial cells inhibited cell proliferation by delaying cell cycle progression through the G 1 phase.…”