Human papillomavirus E5 oncogene protein (HPV E5)

The HPV E5 oncogene protein is a small (about 9.4 kDa), hydrophobic transmembrane protein predominantly found in high-risk HPVs. It localizes to the endoplasmic reticulum, Golgi apparatus, and plasma membrane, where it disrupts normal cell signaling, particularly by activating epidermal growth factor receptor (EGFR) pathways and suppressing apoptosis. E5 is expressed in early stages of HPV infection and contributes to the transformation, enhanced proliferation, and immune evasion of infected cells. It is closely associated with the pathogenesis of HPV-driven cancers and precancerous conditions, particularly in tissues such as the cervix and oropharynx.

Other names

HPV E5 proteinE5 oncoproteinE5α protein (specifically for high-risk HPV types)E5A/E5B (variants in low-risk HPV types)

Indirect targeting via immune-mediated clearance (e.g., therapeutic HPV vaccines); Disruption of oncogenic signaling pathways such as EGFR, PI3K/AKT, and MAPK/ERK; Inhibition of apoptosis through degradation of death receptors (e.g., Fas, TRAIL)