PTGS2 and head and neck squamous cell carcinoma: Aside from the use of Cox-2 inhibitors, the Cox-2-dependent regulation of E-cadherin expression in HNSCC cells was demonstrated in a study using KB cells transfected with Cox-2 cDNA and gene silencing with Cox-2 siRNA, although the specific signaling pathway between Cox-2 and E-cadherin was not referred to [45].