PTGS2 and cancer: In addition to the suppression of the EMT, some other anti-cancer effects of Cox-2 inhibitors in HNSCC have been reported, which include the inhibition of VEGF-A expression by celecoxib [15], the suppression of invasiveness by NS-398 [52,53] and celecoxib [54], the inhibition of proliferation by celecoxib, NS-398, nimesulide, and meloxicam [54,55], and the induction of apoptosis by celecoxib [55].