PTGS2 and skin cancer: The molecular events associated with protective effect of CUR in UVB-induced skin cancer including downregulation of cell proliferative controls, involving thymine dimer, PCNA, apoptosis, transcription factors NF-κB, and inflammatory responses involving COX-2, PGE2, and NO, while upregulation of p53 and p21/Cip1 to facilitate DNA repair.