Expression profiling in early onset colorectal cancer

Background: Causative genes for autosomal dominantly inherited familial adenomatous polyposis (FAP) and hereditary non-polyposis colorectal cancer (HNPCC) have been well characterized. There is, however, another 10-15 % early onset colorectal cancer (CRC) whose genetic components are currently unknown. In this study, we used DNA chip technology to systematically search for genes differentially expressed in early onset CRC. Keywords: disease state analysis Methods: RNA extracted from colonic mucosa of healthy controls(10samples) and patients(12samples) were analyzed using GeneChip U133-Plus 2.0 Array. Patients and controls were age- (50 or less), ethnicity- (Chinese) and tissue-matched. T-test, hierarchical clustering, mean fold-change and principal component analysis were used to identify genes that differentiate between patients and controls. These were subsequently verified by real-time polymerase chain reaction (PCR) technology.