DNA methylation and the Epstein-Barr virus

EBV is a ubiquitous herpesvirus associated with a variety of lymphoid and e pithelial tumors. In healthy lymphocytes and In tumors immune surveillance is evaded by suppression of a family of immunodominant viral antigens. Meth ylation of a viral promoter plays a crucial role in this suppression. Methy lation of the viral genome in the latent statu over evolutionary time is be lieved to account for CPG suppression that distinguishes this virus from mo ss other large DNA viruses. Pharmacologiv manipulation of methylation may o ffer an opportunity to unmask viral antigens and expose tumors to immune su rveillance.