Is ormal mucosa in colon cancer actually abnormal?
Colorectal cancer is one of the most extensively studied tumors at the molecular level. The known genetic alterations from adenoma to frank colon carcinoma have served as a paradigm for tumor progression. Most studies have assumed that morphologically normal colon mucosa is metabolically normal and have used such tissue as a baseline for comparison.In a recent analysis, Chen et al1 attempted to validate this general assumption by comparing gene expression profiles of the so-called normal colon mucosa from patients with colon carcinoma with those from patients without cancer. A total of 15 genes that were altered in the late stages of human colon cancers were analyzed. At least six of them were significantly upregulated in the morphologically normal mucosa from cancer patients, that is, MCSF-1, OPN, IL-8, COX-2, CXCR2 and CD44; whereas at least two genes, PPAR and -, were significantly down regulated. Similar findings were observed in mice carrying a mutation in the adenomatous polyposi
