To further investigate the expression of COX-1 (PTGS1), COX-2 (PTGS2), and COX-related genes in rat oral cancers, a list of COX-related genes was generated using Ingenuity software (http://www.ingenuity.com); integration of this gene list with microarray data from Experiment 1 identified a series of COX-related genes that are up-regulated in rat oral cancers induced by 4-NQO (Table 6). Here, PTGS2 is linked to lip and oral cavity carcinoma.