PTGS2 and hydronephrosis: COX-2 (Nishimura et al. 2008) and mPGES-1 (Yoshioka et al. 2012) were shown to play essential roles in the development of TCDD-induced hydronephrosis in neonatal mice, and cPLA2α was found to play a predominant role in TCDD-induced hydronephrosis by upregulating COX-2 and mPGES-1 (Yoshioka et al. 2014).