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Human endogenous retrovirus K and cancer: Innocent bystander or tumorigenic accomplice?

ABSTRACT: Harbored as relics of ancient germline infections, human endogenous retroviruses (HERVs) now constitute up to 8% of our genome. A proportion of this sequence has been co-opted for molecular and cellular processes, beneficial to human physiology, such as the fusogenic activity of the envelope protein, a vital component of placentogenesis. However, the discovery of high levels of HERV-K mRNA and protein and even virions in a wide array of cancers has revealed that HERV-K may be playing a more sinister role-a role as an etiological agent in cancer itself. Whether the presence of this retroviral material is simply an epiphenomenon, or an actual causative factor, is a hotly debated topic. This review will summarize the current state of knowledge regarding HERV-K and cancer and attempt to outline the potential mechanisms by which HERV-K could be involved in the onset and promotion of carcinogenesis.

SUBMITTER: Downey RF

PROVIDER: S-EPMC6264888 | biostudies-other | 2015 Sep

REPOSITORIES: biostudies-other

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Human endogenous retrovirus K and cancer: Innocent bystander or tumorigenic accomplice?

Downey Ronan F RF Sullivan Francis J FJ Wang-Johanning Feng F Ambs Stefan S Giles Francis J FJ Glynn Sharon A SA

International journal of cancer 20140617 6

Harbored as relics of ancient germline infections, human endogenous retroviruses (HERVs) now constitute up to 8% of our genome. A proportion of this sequence has been co-opted for molecular and cellular processes, beneficial to human physiology, such as the fusogenic activity of the envelope protein, a vital component of placentogenesis. However, the discovery of high levels of HERV-K mRNA and protein and even virions in a wide array of cancers has revealed that HERV-K may be playing a more sini ...[more]

PMID: 24890612

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