Association of high-risk human papillomavirus and breast cancer: a UK based study

Infection by human papillomaviruses (HPVs) has been implicated in the aetiology of a variety of cancers. Studies evaluating the presence of HPVs in breast cancer (BC) have generated considerable controversy. To date, most studies have focused on the presence of viral DNA in BC; however, there are important gaps in evidencing the role of HPV persistence in the invasiveness of BC. In view of the above, the investigation of HR-HPVs as promoting factors for breast cancer remains unclear. While these studies have been conducted in several countries, none, on the presence and biological activity of high risk (HR) HPV in BC has been done in the UK. Hence, this study aimed to investigate these gaps by screening a total of 110 fresh breast tissue specimens from UK patients for the presence of twelve HR-HPV types DNA using PCR and Sanger sequencing. Samples positive for HPV-DNA were screened for viral oncoprotein expression using western blot, dot blot and IHC. In addition, the presence of Koilocytes were investigated in samples tested positive for HPV. Data obtained showed the presence of HR-HPVs in 42% of breast tissues of which the viral activity was only confirmed in a number of pre-cancerous and some invasive carcinomas. These findings, the first to report in the UK, suggest that the presence and expression of viral oncoprotein in pre-cancerous and invasive cases may propose a role for HR-HPVs in the development of some types of BC.