Carcinogenic Potential of Biliary Epithelium of Congenital Choledochal Cyst Model in Rats: A Special Reference to HDAC Expression.

BACKGROUND/AIMS: Pancreaticobiliary maljunction (PBM) is well known to have carcinogenic potential. The goal of this study was to clarify the carcinogenic potential of the epithelium of choledochal cyst particularly by paying attention of HDAC1 and COX-2 expressions.

METHODOLOGY: Six-week male Lewis rats were divided into two groups; 1) single dose of dibutyltin dichloride (8 mg/kg) was administered intravenously (DBTC group), 2) saline administration was done with the same manner (control group). Morphological changes of biliary tract and expressions of carcinogenesis-related genes, Ki67, HDAC1 and cyclooxygenase-2 (COX-2) were examined immunohistochemically after administration.

RESULTS

In the DBTC group, the bile duct had been gradually dilated on day 3 after administration and the biliary epithelium of dilated bile duct was papillary proliferated on day 7. Ki67 and COX-2 expressions gradually increased and reached the highest value of 6.0% and 3.6% on day 14, respectively. HDAC1 expression increased at the early postoperative period prior to other oncogene, and reached the highest level of 15% on day 7.

CONCLUSIONS

These findings suggested that HDAC1 played an important role in carcinogenesis of PBM through the regulation of COX-2.