Pathogenic role of Epstein-Barr virus in human cancer.

Epstein-Barr virus (EBV) is detected in several human cancers, such as Burkitt's lymphoma (BL), nasopharyngeal carcinoma, gastric cancer, and peripheral T-cell lymphoma. However, the role of EBV in the development of these cancers is still controversial. During cultivation of the EBV-positive BL line Akata, we found that EBV DNA is lost from some of the cells. Isolation of EBV-positive and -negative cell clones with the same origin made it possible to examine the effects of EBV in BL cells. The results indicate that malignant phenotypes of BL, such as the growth in low serum, anchorage-independent growth, and tumorigenicity in nude mice, are dependent on the presence of EBV genomes and underline the oncogenic function of EBV in human cancer.