PTGS2 and prostate cancer: DU-145 prostate cancer cells respond to TNF-α treatment with an increased expression of PTGS2, of COX-2 and of PGE2 production [38] and this is accompanied by a decreased expression of NAPEPLD without change in NAAA or FAAH expression [29], thereby producing an imbalance in PTGS2/NAPEPLD (Figure 2).