Inflammatory and Non-inflammatory Breast Cancer: A Potential Role for Detection of Multiple Viral DNAs in Disease Progression

Inflammatory breast cancer (IBC) is the most lethal form of breast cancer. Multiple viral infections in IBC tissues were found to be associated with disease pathogenesis. The aim of the present study was to correlate the incidence of viral DNA with breast cancer progression. Overall, 135 women diagnosed with breast cancer were enrolled in this study. Using polymerase chain reaction and sequencing assays, we determined the incidence of human papillomavirus types 16 and 18 (HPV-16 and -18), human cytomegalovirus (HCMV), Epstein-Barr virus, human herpes simplex virus type 1 and 2, and human herpes virus type 8 (HHV-8) in breast carcinoma tissue biopsies. We also assessed the expression of the cell proliferation marker Ki-67 by immunohistochemistry in association with the incidence of viral DNA. HCMV and HPV-16 were the most detected viral DNAs in breast carcinoma tissues; however, the frequency of HCMV and HHV-8 DNA were significantly higher in IBC than non-IBC tissues. Moreover, the prevalence of multiple viral DNAs was higher in IBC than non-IBC tissues. The incidence of multiple viral DNAs positively correlates with tumor size and number of metastatic lymph nodes in both non-IBC and IBC patients. The expression of Ki-67 was found to be significantly higher in both non-IBC and IBC tissues in which multiple viral DNAs were detected. The incidence of multiple viral DNAs in IBC tissues was higher compared with non-IBC tissues. The present results suggest the possibility of a functional relationship between the presence of multiple viral DNAs and disease pathogenesis.