The epithelial-mesenchymal transition (EMT) is regulated by oncoviruses in cancer

The epithelial-mesenchymal transition (EMT), defined as transdifferentiation of epithelial cells into mesenchymal cells, is critical for embryonic development, wound healing, tissue regeneration, organ fibrosis, and cancer progression. Recently, the role of EMT in carcinogenesis has attracted much attention. Oncoviruses, including human papillomaviruses (HPVs), Epstein-Barr virus (EBV), and hepatitis B and C viruses (HBVs, HCVs), are known to be involved in the etiology of cancer and have been found to play important roles in cancer metastasis, especially in the EMT process. The HPV encoded oncoproteins E6 and E7 (E6/E7), EBV latent membrane protein-1 and -2A, EBV nuclear antigen, HBV-encoded X antigen, and nonstructural HCV protein 5A are all involved in the regulation of EMT. This review primarily focuses on the role of oncoviruses and their encoded proteins or signaling pathways in the EMT process. Understanding their roles will help us in the development of effective strategies for prevention and treatment of virus-related cancers.-Chen, X., Bode, A. M., Dong, Z., Cao, Y. The epithelial-mesenchymal transition (EMT) is regulated by oncoviruses in cancer.