The cellular
prion protein (PrPC) is a
glycoprotein anchored to the cell surface by
glycosylphosphatidylinositol (GPI). PrPC is expressed both in the brain and in peripheral tissues. Investigations on PrPC's functions revealed its direct involvement in neurodegenerative and
prion diseases, as well as in various physiological processes such as anti-oxidative functions,
copper homeostasis, trans-membrane signaling, and cell adhesion. Recent findings have revealed the ectopic expression of PrPC in various
cancers including gastric,
melanoma, breast, colorectal, pancreatic, as well as rare
cancers, where PrPC promotes cellular migration and invasion,
tumor growth, and
metastasis. Through its downstream signaling, PrPC has also been reported to be involved in resistance to
chemotherapy and
tumor cell apoptosis. This review summarizes the variance of expression of PrPC in different types of
cancers and discusses its roles in their development and progression, as well as its use as a potential target to treat such
cancers.