PTGS2 and skin cancer: Basing on its potent anti-OS, anti-mutation and anti-carcinogenesis properties, luteolin directly inhibits protein kinase C (PKC) ε/Src activities and prevents keratinocytes from UVB-induced DNA damage to positively combat skin cancers through attenuating the expressions of COX-2, AP-1 and NF-κB as well as their upstream signals (e.g. MAPKs and Akt) and suppressing UVB-induced OS and cyclobutane pyrimidine dimers (CPDs) formation [109, 110].