Golgi phosphoprotein 2 (GOLPH2, also known as GP73 or GOLM1) is a resident Golgi type-II membrane protein. It is predominantly expressed in the epithelial cells of many human tissues. GOLPH2 traffics through endosomes and can be secreted into the circulation. Its expression is upregulated in a number of tumors and GOLPH2 could be a promising serum marker for hepatocellular carcinoma.