YPEL1 is a nuclear protein that is suggested to be involved in mesenchymal to epithelial-like transition during tissue development. Recently we have identified YPEL1 as a gene whose expression is deregulation in perineural invasive pancreatic cancer cells. In this study we assessed the expression of YPEL1 in normal and diseased pancreatic tissues and pancreatic cancer cell lines. Quantitative real time polymerase chain reaction was used to analyze the expression of YPEL1 mRNA in nine cultured pancreatic cancer cell lines and pancreatic bulk tissues of the normal pancreas (n=19), chronic pancreatitis (n=19) and pancreatic adenocarcinoma tissues (n=31). Quantitative real time polymerase chain reaction analysis revealed a significant down-regulation of YPEL1 mRNA expression in pancreatic adenocarcinoma tissues compared to normal tissues (54.1+/-5.2 vs. 85.8+/-14.1 copies/10,000 copies cpb) and low expression of this gene indicated a tendency for better survival of pancreatic cancer patients (16 vs. 13 months; p=0.17). Expression of YPEL1 mRNA was present in all tested pancreatic cancer cell lines with comparably low to moderate expression levels of 4.3 - 88.0 copies/10,000 copies cpb. Reduced expression of YPEL1 in pancreatic cancer might be related to perineural invasion. and prognosis. YPEL1 might be an important factor during the development and malignant transformation of tissues. Further studies are required to better assess the role of human YPEL1 in pancreatic cancer pathogenesis.