HPV-associated oncogenesis in head and neck cancer
Vjekoslav Tomaić, Nina Milutin Gašperov, Ivan Sabol, Magdalena Grce
More than 200 human papillomaviruses (HPVs) infect human epithelial cells, and out of them alpha and beta types have been the most extensively investigated and analysed. Alpha HPVs primarily infect mucosal epithelia and only a small proportion of them is associated with more than 600,000 cancers per year worldwide at various anatomical sites, especially anogenital and head-and-neck region. Of these the central disease is cervical cancer, which is the leading cause of cancer-related deaths in women in numerous parts of the world. HPVs encode two oncoproteins, E6 and E7, which are directly involved in the development of HPV-mediated malignancies. They do this in cooperation by targeting various cellular pathways involved in the regulation of cell cycle control, of apoptosis and of cell polarity control networks. In this review, the biological consequences of HPV manipulating of various cellular proteins at diverse anatomical sites in the development of HPV-induced carcinogenesis are depicted, with focus on head and neck cancer.