Association of Epstein-Barr virus infection and breast carcinoma

A controversy regarding the association of Epstein-Barr virus (EBV) with breast carcinomas has recently been reported in the literature. The present study was carried out in an attempt to determine whether there is a relationship between latent infection with EBV and breast carcinomas in Jordanian females.

Extraction of DNA from the archive samples of breast carcinoma cases embedded in paraffin wax was performed and the extracted DNA was subjected to polymerase chain reaction amplification to detect the EBV genome using four sets of primers for EBER 2, BNLF-1, EBNA 2, and Gp220. Immunohistochemistry study was performed on sections of 4 µm which were cut from paraffin blocks of tumor and control groups. Monoclonal antibody against EBNA-1 was applied to all slides to identify the EBV-infected tumor cells. Detection was performed using the Dako envision dual link system.

DNA was successfully extracted from 92 paraffin embedded samples of breast carcinoma patients, and from 49 normal samples. The extracted DNA was confirmed by using glyceraldehyde-3-phosphate-dehydrogenase (GAPDH) primers. Twenty-four out of 92 breast carcinoma specimens was found to be infected with EBV as compared to 3 out of 49 control group specimens, which represented a statistically significant difference (p-value using χ(2) = 0.008). Immunohistochemically, 24 (26%) of the 92 studied samples were found to be positive, showing EBNA-1 granular nuclear staining in tumor epithelial cells.

These findings suggest an association between EBV infection and breast carcinoma development.