The oncogenic potential of Epstein-Barr virus

Epstein-Barr (EB) virus is a herpesvirus which is the causative agent of infectious mononucleosis. It can also be classified as a human DNA tumor virus as it is also etiologically associated with the development of Burkitt's lymphoma (BL) and nasopharyngeal carcinoma. EB virus involvement in these human tumors is suggested by seroepidemiological studies and the detection of virus DNA and proteins in tumor biopsies. Furthermore, EB virus can be detected in lymphoproliferations and malignant tumors arising from immunosuppressed individuals which further emphasizes its oncogenic potential. EB virus immortalizes B lymphocytes in vitro giving rise to continuously proliferating lymphoblastoid cell lines (LCL). These LCL are not tumorigenic, which suggests that cellular infection by virus alone is not sufficient for full tumorigenicity. This has led to the development of a multistep scenario for the development of BL where EB virus, in conjunction with other suggested cofactors, is necessary to induce the tumorigenic phenotype.