MAOA and colorectal carcinoma: First, we surveyed mRNA expression levels of MAOA and MAOB in CRC tissues from three available online databases, Prediction of Clinical Outcome from Genomic Profiles (PRECOG), SurvExpress, and Gene Expression Omnibus (GEO), and also performed immunohistochemical (IHC) staining of MAOA and MAOB using CRC tissue microarrays (TMAs).