1696P - Cancer Stem Cell Markers in Clinical Pancreatic Cancer: Impact of CD44 + /CD24 + /EPCAM+ Expression on Histology and Prognosis

Abstract

ABSTRACT Purpose Emerging evidence suggests that the capability of a tumor to grow and propagate is dependent on a small subset of cells within it, termed cancer stem cells (CSCs). In pancreatic cancer, CD44 + /CD24 + /EpCAM+ cells have been reported to be CSCs; however, the histological and clinical importance of these cells has not yet been investigated. Here we clarified the characteristics of CD44 + /CD24 + /EpCAM+ cells in clinical specimens of pancreatic cancer using immunohistochemical assay. Materials and methods We used surgical specimens of pancreatic ductal adenocarcinoma from 30 patients. In view of tumor heterogeneity, we randomly selected 10 high-power fields per case, and triple-positive CD44 + /CD24 + /EpCAM+ expression was identified using our scoring system. The distribution, histological characteristics, and prognostic importance of CD44 + /CD24 + /EpCAM+ cells were then analyzed. Results Among a total of 300 assessed fields, 41 (14%) were evaluated as triple-positive. The distribution of CD44 + /CD24 + /EpCAM+ cells varied widely among the 30 cases examined, and CD44 + /CD24 + /EpCAM+ expression was correlated with poor glandular differentiation and high proliferation (high Ki-67 labeling). Analysis of the three markers individually showed that CD44 and CD24 were also correlated with poor differentiation and high proliferation, while EpCAM was not. Survival analysis showed that CD44 + /CD24 + /EpCAM+ expression was not correlated with patient outcome; however, CD44 and CD24 each appeared to be correlated with poor prognosis. Conclusion In pancreatic cancer, CD44 + /CD24 + /EpCAM+ cells overlapped with poorly differentiated cells and possess high proliferative potential. In particular, double-positive CD44 + /CD24+ cells seem to have relevance when considering clinical aspects. Disclosure All authors have declared no conflicts of interest.