Overexpression of vitamin D receptor indicates a good prognosis for cholangiocarcinoma: Implications for therapeutics

Abstract

BACKGROUND. Up-regulation of vitamin D receptor (VDR) expression has been shown in several tumors and is thought to represent an important endogenous response to tumor progression. The authors aimed to verify the expression of VDR and its clinical significance in histologically proven cholangiocarcinoma (CCA). METHOOS. The antiproliferative activity of vitamin D3 on CCA cell lines was explored. The immunohistochemistry of 111 paraffin-embedded CCA tissues showed that VDR expression gradually increased during CCA development. Normal bile duct epithelium rarely expresses VDR, whereas more than 74% of CCA tissues showed positive VDR staining, of which 40% were high. Approximately 80%-90%of CCA patients with papillary and well differentiated adenocarcinomas had positive VDR expression in tumor tissues, whereas 39% positive VDR expression was found in those with poorly differentiated CCAs (P