ABSTRACT
This chapter examines the methodology for analysis of gene expression in small mucosal biopsies that can be obtained from the colon and rectum of patients at varying relative risk for development of tumors. It summarizes experiments that have identified genes that distinguish two groups at high risk for development of colorectal cancer from a group at low risk. The chapter summarizes the nature of the genes involved, and the utility of one of the sequences for monitoring response of the colonic mucosa in high-risk individuals to daily calcium supplementation. It outlines how this panel of sequences may be used in future intervention studies. The chapter investigates the effects of calcium on the level of expression of this gene in the colonic mucosa of high-risk group–hereditary nonpolyposis colon cancer (hnpcc) individuals. Calcium was given to hnpcc patients as a dietary supplement of 1,500 mg/day calcium carbonate.
