In addition, PAX6 methylation has previously been observed to occur frequently in colorectal and other cancers, EYA2 is methylated in colorectal cancer, NKX2-1 is methylated in thyroid cancer, SALL3 is methylated in hepatocellular carcinoma, TCF2 in ovarian cancer and TFAP2A is methylated in large B-cell lymphoma, breast and kidney cancers [18-20,29-33]. This evidence concerns the gene NKX2-1 and colorectal cancer.