Preferential expression of cartilage oligomeric matrix protein in degenerating acinar cells in chronic pancreatitis and in chronic pancreatitis-like lesions

OBJECTIVES: To study cartilage oligomeric matrix protein (COMP) mRNA and protein expression in normal pancreas, chronic pancreatitis (CP), and pancreatic cancer tissues. METHODS: Tissues from 15 cases of normal pancreas, 14 cases of chronic pancreatitis and 14 cases of pancreatic cancer were analyzed by Northern blot, Western blot, in situ hybridization and immunohistochemistry. RESULTS: COMP mRNA signals and immunoreactivity were strongly present in the cytoplasm of degenerating acinar cells in CP tissues as well as in CP-like lesions in pancreatic cancer tissues. In contrast, COMP expression was weak to absent in the cytoplasm of cancer cells in pancreatic cancer tissues, and in ductal cells and islet cells in normal pancreatic tissues. CONCLUSION: COMP is preferentially expressed in degenerating acinar cells in CP and in CP-like areas in pancreatic cancer, suggesting a potential role of this molecular in acinar cell dysfunction in CP.