PTGS2 and infection: In OSCC, PTGS2 involves an inflammatory response to infection by promoting tumorigenesis (Cacina et al., 2018) and activating transcription factor 3 (ATF3), one of the 8 hub genes that regulate the PTGS2 during acute inflammation (Hellmann et al., 2015) and helps in the homeostasis of the metabolism and immune system (Sha et al., 2017).