Expression of clusterin in human pancreatic cancer.

Abstract

Clusterin, also known as apolipoprotein J, has been implicated in numerous processes, including active cell death. Clusterin is reported to be overexpressed in breast and prostate cancers. However, its expression in pancreatic cancer is yet to be reported. To examine clusterin expression and apoptosis in 52 pancreatic tissues, including specimens from 33 cases of pancreatic cancer, by immunohistochemistry. Clusterin was expressed in 49% (16) of 33 cases of pancreatic cancer, 50% (13) of 26 cases of chronic pancreatitis, and 67% (4) of 6 cases of mucinous cystadenoma. It was not expressed in normal pancreas. Clusterin mRNA was also expressed in the pancreatic cancer cell lines. Clusterin was significantly more highly expressed at stage I and II (well-differentiated and moderately differentiated cancers). Clusterin and apoptosis were localized in the same cells in pancreatic cancer. However, clusterin expression was not significantly associated with apoptosis in any pancreatic disease. Clusterin-positive patients with pancreatic cancer survived significantly longer. These results suggest that clusterin expression is induced in pancreatic cancer as well as chronic pancreatitis and that downregulation of clusterin may be involved in the progression of pancreatic cancer.