Identification of Integration Sites of Mouse Mammary Tumor Virus in Blood Samples from Breast Cancer Patients

Abstract

Breast Cancer is the most common form of cancer diagnosed in women. Many factors are involved in mammary tumorigenesis; genetic and epigenetic factors. Viruses have also been implicated to play a role in Breast cancer. Mouse mammary tumor virus (MMTV) is an established cause of mammary tumors in mice but its role in human breast cancer is still to be understood. MMTV has been detected in human breast cancer samples but the establishment of a causal role is controversial. This study presents the hypothesis that integration of a virus may present with a good understanding of how MMTV might play a role in oncogenesis. Detection of 630 bp of MMTV LTR sequences in 40% of blood samples of invasive ductal carcinoma and identification of seven distinct integration sites lends support to the idea of a viral link to breast cancer. Our data suggests that integration in the genome might give cells a distinct advantage for survival of transformed cells. Although it is still not very clear, but there exists a possibility that an MMTV-like virus is implicated in human breast cancer.