Promotion of Tumorigenesis and Clinical Implications of Viral Infection in Breast Cancer

Abstract

The prevalence of breast cancer is rising worldwide. The main cause of death from breast cancer is distant metastasis, which occurs within 3 years after diagnosis in 10-15% of patients. The initiation and progression of breast cancer have been related to both external and internal factors, including viral infection. Human cytomegalovirus infection (HCMV) is common in breast cancer and metastases, and high tumor levels of HCMV appear to worsen outcomes. HCMV can increase the malignant behavior of tumor cells by modulating multiple cellular regulatory and signaling pathways and enhance the proliferation, survival, invasion, motility, and adhesion of tumor cells. Although HCMV seems to have an oncomodulatory role in breast cancer, definitive evidence for a causal role is lacking, and further studies are needed. The current review will discuss evidence that links viral infections to breast cancer.

Association of Epstein–Barr Virus and Cytomegalovirus Infections with Esophageal Carcinoma

“…CMV is a member of herpesviridae family and infects a major part of the human population with lifelong persistence (14). CMV replicates in a spectrum of human cells, especially endothelial cells and macrophages, and may produce latency infection (15). Regarding the possible mechanisms involved in CMV carcinogenesis, it has been reported that immediate-early protein (IE) 86 prevents the inhibitory functions of pRb, resulting in the release of E2F and induction of cell cycle (16).…”