Detection of HPV, EBV, MMTV- like DNA Sequences in Breast Cancer Patients

Abstract

Breast cancer is known to affect every ninth women in Pakistan. Besides, genetic predisposition being a leading cause of this carcinoma, the oncogenic potential of Mouse mammary tumor virus (MMTV), Human Papilloma Virus (HPV), and Epstein Barr Virus (EBV) is also a reported cause behind the cancer. MMTV has a significant role as it is speculated to be a causative agent to breast cancer. On the contrary, HPV and EBV are not known to be directly causing the cancer. However, these viruses, upon integration, result in the down regulation of tumor suppressor genes whereas in the up regulation of proto oncogenes, thus causing breast carcinoma. The direct role of viruses in the disease is still a debatable argument. The study was therefore designed by keeping this in mind and therefore both tissue and blood samples of the patients were analyzed for the presence of the aforementioned viruses, to ensure credibility of the results. Mean Mono-infection of these viruses was observed in 39 % cases and co-infection of MMTV, EBV and HPV was 32 %, suggesting that co-infection as well as mono infection of EBV, MMTV LTR and HPV is significantly associated with studied samples of breast carcinoma. The coinfection of EBV is also observed to play a significant role in cancer metastasis through lymph node, however, no significant association of these viruses was found with tumor grade, breast cancer types and age of patients. A limitation of the study was its lesser sample size; however, further studies in this area encompassing a larger sample size will help us analyze the prevalence of these viruses in a better way.