PTGS2 and oral mucositis: Japanese traditional medicine (Kampo) Hangeshashinto (TJ-14) effectively relieves chemotherapy-induced oral mucositis in gastric cancer and colorectal cancer patients by anti-oxidation and anti-inflammation (Matsumoto et al., 2015; Nishikawa et al., 2018) or suppression of inflammatory cell chemotaxis and cyclooxygenase-2 (COX2) expression (Kamide et al., 2017).