Proliferating cell nuclear antigen shRNA treatment attenuates chronic proliferative cholangitis in rats

Abstract

Chronic proliferative cholangitis (CPC) is currently considered as a pathological basis and major cause for the high recurrence rate of intrahepatic stones. Since CPC is a form of chronic proliferative disease, this study was designed to preliminarily investigate the inhibitory effect of proliferating cell nuclear antigen (PCNA) shRNA on the hyperplastic behavior and lithogenic potentiality of CPC. The rat model of CPC was given an intralumenal administration of 0.5 mL PCNA shRNA through a 20-gauge venous retained needle. PCNA shRNA-mediated effects on CPC-associated hyperplastic behavior and lithogenic potential were assessed by investigating histological changes, immunohistochemistry for Ki-67, biochemistry for beta-glucuronidase, real-time polymerase chain reaction, and western blot analysis of PCNA, procollagen I, and mucin-3. PCNA shRNA treatment could efficiently inhibit the mRNA and protein expressions of the proliferation-related gene, PCNA, and Ki-67, which efficiently inhibited the hyperplastic behavior of the biliary epithelium, submucosal gland, and collagen fibers in the diseased bile duct wall. This novel treatment could efficiently inhibit the formation of acidic mucus glands, the expression of mucin-3 mRNA, and the secretion of endogenous beta-glucuronidase, thus effectively inhibiting the lithogenic potentiality of CPC. A further analysis revealed that PCNA shRNA-1 might display a more robust inhibitory effect on CPC-associated hyperplastic behavior and lithogenic potential than other gene sequences targeted in this study. PCNA shRNA-1 treatment could effectively inhibit the hyperplastic behavior and lithogenic potentiality of CPC, which might facilitate the prevention of stone recurrence and biliary restenosis.