Similar to cyclooxygenase (COX)-2 being overexpressed in canine UC cells [47], most canine prostatic carcinomas also express COX-2, whereas this enzyme is not expressed in normal prostatic tissue [22, 48, 49], and COX-2 inhibitors (NSAIDs) are used for PCA treatment with acceptable side effects [22]. This evidence concerns the gene PTGS2 and prostate carcinoma.