Also in 2004, Sakamoto et al. showed that overexpression of COX-2 and underexpression of PPARγ in ovarian epithelial cells were strongly implicated in ovarian carcinogenesis and that PPARγ activation in ovarian cancer cells inhibited COX-2 expression via the nuclear factor-kappa B (NFκB) pathway [23]. Here, PTGS2 is linked to ovarian carcinoma.