Loss of imprinting of IGF2 as an epigenetic marker for the risk of human cancer

Issue title: Epigenetic Markers

Article type: Research Article

Authors: Cui, Hengmi

Affiliations: Division of Molecular Medicine, Department of Medicine, Johns Hopkins University School of Medicine, 1064 Ross/720 Rutland Avenue, Baltimore, MD 21205, USA

Note: [] Corresponding author. Tel.: +1 410 502 4081; Fax: +1 410 614 9819; E-mail: [email protected]

Abstract: IGF2 is the first gene discovered to be imprinted and expressed exclusively from the paternal allele in both human and mouse. IGF2 is also the first imprinted gene displaying loss of imprinting (LOI) or aberrant imprinting in human cancers. Evidently, LOI or reactivation of the maternal allele of IGF2 is associated with an increase of IGF2 expression that may subsequently play an important role in the onset of human cancers. The most important discovery was the association of LOI of IGF2 with the risk of developing human colorectal cancer. LOI occurs not only in colon cancer tissues, but also in matched normal tissues and peripheral blood cells. A pilot study indicated a significant relationship between LOI of IGF2 and family history as well as personal history of colorectal cancer, suggesting that LOI of IGF2 might be a valuable biomolecular marker of predicting an individual's risk for colon cancer. A recent epigenetic progenitor model suggested that human cancers might have a common basis that involves an epigenetic disruption of progenitor cells mediated by "tumor progenitor genes" and proposed that non-neoplastic but epigenetically disrupted progenitor cells might be an important target for cancer risk assessment and prevention.

Keywords: IGF2, loss of imprinting, cancer, biomarker

Journal: Disease Markers, vol. 23, no. 1-2, pp. 105-112, 2007