Epigenetic alterations in intraductal papillary mucinous neoplasms of the pancreas.

Intraductal papillary mucinous neoplasm (IPMN), an increasingly recognized cystic neoplasm of the pancreas with a broad spectrum of malignant potential, has been considered a precursor to infiltrating ductal adenocarcinoma. Because of its unique clinical, radiological, pathological, and molecular features, IPMN has attracted considerable interest among clinicians and researchers. Although some genetic alterations have been described in IPMNs, the molecular features that characterize the evolution and progression of these neoplasms are largely unknown. Recent studies have shown that aberrant methylation of the promoter cytosine-phospho-guanine (CpG) island is a common mechanism associated with the silencing of tumor-suppressor and cancer-related genes in IPMNs. Importantly, the prevalence of such methylation increases along with the grade of neoplasia, suggesting that these epigenetic events may contribute to the progression of IPMNs. Further studies of epigenetic alterations in IPMN will shed light on the molecular pathogenesis of this unique neoplasm and lead to the identification of epigenetic markers that can be applied in the clinical setting.