Expression and clinical significance of IMP3 in microdissected premalignant and malignant pancreatic lesions.

Abstract

Insulin-like growth factor 2 (IGF-2) mRNA-binding protein 3 (IMP3) is overexpressed in pancreatic cancer, while remaining undetectable in the normal pancreas, indicating its important role in pancreatic cancer pathogenesis. The role of IMP3 in pancreatic carcinogenesis has not been fully understood. The main goal of this study was to probe the expression profile of IMP3 in different stages of pancreatic ductal adenocarcinoma (PDAC) development, and evaluate their prognostic significance in PDAC patients. We used quantitative real-time RT-PCR combined manual microdissection to precisely detect IMP3 expression in 97 microdissected foci from 50 patients with PDAC. Nonparametric test, Log-rank test and Cox regression analysis were used to evaluate the clinical significance of DNMTs expression. Expression of IMP3 increased from normal duct to pancreatic intraductal neoplasia and to PDAC. IMP3 mRNA expression statistically correlated with TNM staging. Univariate analysis showed that high level of IMP3 expression, tumor differentiation, TNM staging and alcohol consumption were statistically significant risk factors. Multivariate analysis showed that high level of IMP3 expression and tumor differentiation were statistically significant independent poor prognostic factors. These results suggested that pancreatic carcinogenesis involves an increased IMP3 mRNA expression, and it may become valuable diagnostic and prognostic markers as well as potential therapeutic targets for pancreatic cancer.