A Pilot Study as the Biochip Based Gene Expression Profiling in Patients with Hyperplastic Colonic Polyp

ABSTRACT

PURPOSE: A microarray-based gene expression analysis may offer a rapid and efficient means for assessing. However, the molecular genetic change in nonneoplastic colonic polyp is still poorly understood. To elucidate the molecular genetic basis, We now report the results of our initial microarray data to analyze the genom pattern in patients with hyperplastic polyps of colon. METHODS: 36 samples (18 pairs of colonic polyps and normal colonic mucosa were) harvested from colonoscopic biopsy. 3 of 18 colonic polyps were pathologically identified as the serrated type of hyperplastic polyp. We used the oligonucleotide microarray technique for analysis of the expression profiles of serrated polyps and normal mucosa. For the identification of differentially expressed genes, SAM (Significance Analysis of Microarray) package method was used. The result was analysed by using global normalization, intensity dependent normalization and block-wise normalization. RESULTS: Polypectomy specimens microscopically showed the pathologically characteristic serration with a saw-teeth like luminal border (branching of the crypts). 8 genes including RHEB (Ras homolog enriched in brain), WASF2 (WAS protein family, member 2), TYRP1 (Tyrosinase-related protein 1), VSX1 (Visual system homeobox 1 homolog), ROS1 (V-ros UR2 sarcoma virus oncogene homolog 1), WEE1 (WEE1 homolog), TEC (Tec protein tyrosine kinase), TNFRSF10A (Tumor necrosis factor receptor superfamily, member 10a) in serrated polyp were up-regulated by more than 10 times as compared with normal colonic mucosa. On the other hand, 6 genes including SIAT7D (Sialyltransferase 7D), DRD1 (Dopamine receptor D1), SIAT1 (Sialyltransferase 1), ITSN1 (Intersectin 1), TNFSF12 (Tumor necrosis factor superfamily, member 12), CHES1 (Checkpoint suppressor 1) were down-regulated by less than a tenth of the expression as compared with normal colonic mucosa. CONCLUSIONS: Serrated polyps as a subset of hyperplastic colonic polyps were analyzed with the oligonucleotide microarray technique. We authors could identify 14 genes (8 up-regulated and 6 down-regulated genes) that showed the significant change of expression as compared with normal colonic mucosa. Specifically, we believe that current study will serve as a fundamental base to offer a bioinformative characteristics of the serrated colonic polyp in future clinical applications.