Analysis of Epstein-Barr virus reservoirs in paired blood and breast cancer primary biopsy specimens by real time PCR

R Serene Perkins¹^,2^,3^,4, Katherine Sahm⁵, Cindy Marando¹^,2, Diana Dickson-Witmer⁵, Gregory R Pahnke⁵, Mark Mitchell⁵, Nicholas J Petrelli⁵, Irving M Berkowitz⁵, Patricia Soteropoulos⁶, Virginie M Aris⁶, Stephen P Dunn²^,3 and Leslie J Krueger¹

¹Molecular Genetics, Cellular and Tissue Transplantation, Nemours Biomedical Research, Rockland Road, Wilmington, DE 19803, USA

²Department of Surgery of the Alfred I duPont Hospital for Children, Rockland Road, Wilmington, DE 19803, USA

³Thomas Jefferson University, Jefferson Medical College, Department of Surgery, Walnut Street, Philadelphia, PA 19107, USA

⁴Oregon Health and Science University, Department of Surgery, Portland, OR 97239-3098, USA

⁵Helen F Graham Cancer Center, Christiana Care Health System, Ogletown Stanton Road, Newark, Delaware 19713, USA

⁶Center for Applied Genomics, Public Health Research Institute, Warren Street, Newark, NJ 07103, USA

author email corresponding author email

Breast Cancer Research 2006, 8:R70doi:10.1186/bcr1627


Published:	12 December 2006

Abstract

Introduction

Epstein-Barr virus (EBV) is present in over 90% of the world's population. This infection is considered benign, even though in limited cases EBV is associated with infectious and neoplastic conditions. Over the past decade, the EBV association with breast cancer has been constantly debated. Adding to this clinical and biological uncertainty, different techniques gave contradictory results for the presence of EBV in breast carcinoma specimens. In this study, minor groove binding (MGB)-TaqMan real time PCR was used to detect the presence of EBV DNA in both peripheral blood and tumor samples of selected patients.

Methods

Peripheral blood and breast carcinoma specimens from 24 patients were collected. DNA was extracted and then amplified by MGB-TaqMan real time PCR.

Results

Of 24 breast tumor specimens, 11 (46%) were positive for EBV DNA. Of these 11 breast tumor specimens, 7 (64%) were also positive for EBV DNA in the peripheral blood, while 4 (36%) were positive for EBV DNA in the tumor, but negative in the blood.

Conclusion

EBV was found at extremely low levels, with a mean of 0.00004 EBV genomes per cell (range 0.00014 to 0.00001 EBV genomes per cell). Furthermore, our finding of the presence of EBV in the tumor specimens coupled to the absence of detection of EBV genomic DNA in the peripheral blood is consistent with the epithelial nature of the virus. Because of the low levels of viral DNA in tumor tissue, further studies are needed to assess the biological input of EBV in breast cancer.