Epstein-Barr virus (EBV) is a member of the herpesvirus family and one of the most common human viruses. The virus can be found all over the world, and most people become infected with EBV sometime during their lives. In the United States, as many as 95% of adults between 35 and 40 years of age have been infected with EBV. Infections usually cause no symptoms or are indistinguishable from the other mild, brief illnesses of childhood. When infection with EBV occurs during adolescence or young adulthood, it causes infectious mononucleosis.
Epstein-Barr virus has been previously linked to skin and gastric cancer, Hodgkin's lymphoma, as well as cancer of the salivary glands and thymus. New studies have detected EBV in breast cancer specimens and have prompted researchers to examine the effect of infection with EBV on anticancer drug treatment.
Researchers from France and Japan report that presence of Epstein-Barr virus in the breast cancer tissue and tumor cells may impact the efficiency of chemotherapeutic drug treatment. They report their findings in the January 2006 issue of the Journal of Virology.
In the study, the researchers examined biopsy specimens of breast cancer tissue for the presence of EBV, which was identified in about half of the specimens. However they found that, the viral load was highly variable among different tumor specimens. These findings indicate that EBV may not be the cause of breast cancer, but it may lead to tumor progression. Researchers also studied the EBV infected cells in the laboratory and found that the tumor cells containing EBV are more resistant to chemotherapy drugs.like taxol. They found that this resistance is due to overexpression of a gene called the multidrug resistance gene (MDRI).
The researchers say that even if a small number of breast cancer cells are EBV infected, the impact of EBV infection on the efficiency of anticancer treatment might very significant and more research is needed in this direction. |
