k-type human endogenous retroviral elements in human melanoma

Liliana Rincon,1 Michael P Sedrak,1 Huijian Sun,2 Gregorio Garza,3 Brent Kelly,4 Jianli Dong11Department of Pathology, 2School of Medicine, University of Texas Medical Branch, TX, USA; 3Ciencias de la Salud, Universidad de Monterrey, Nuevo León, Mexico; 4Department of Dermatology, University of Texas Medical Branch, TX, USAAbstract: Human endogenous retroviral elements (HERVs) are thought to be germline-integrated genetic remnants of exogenous retroviral infections. HERVs comprise approximately 5%–8% of the human genome. Although all HERV genomes are highly defective, some, especially the K type (HERV-K), have the potential to be expressed and have biological activities. HERV-K expression has been detected in human melanomas. There are also reports on the regulation and potential activities of HERV-K in melanoma cells. Although a causal link between the activation of HERV-K and melanoma development has yet to be determined, existing data support the further research efforts in this area. In this review, we summarize the published studies on the expression, regulation, and activity of HERV-K in human melanoma.Keywords: HERV, HERV-K, melanoma development