ERVW-1 and brain cancer: Additionally, human cytomegalovirus—a betaherpesvirus implied to be present with high prevalence in many brain cancers [254,255,256,257,258]—was shown to induce upregulation of HERV-W alongside HERV-T, HERV-F, ERV-9, HERV-K (HML-2 to 4 and HML-7 to 8), and HERV-L elements in GliNS1 cells [259].