Human Papillomavirus type 16 E6 and E7 oncoproteins (HPV-16 E6/E7)

Human Papillomavirus type 16 (HPV-16) E6 and E7 are the primary oncoproteins responsible for the development and maintenance of HPV-associated malignancies, such as cervical, oropharyngeal, and anal cancers [1, 3]. E6 facilitates the degradation of the tumor suppressor protein p53 by recruiting the E6AP ubiquitin ligase, while E7 binds and inactivates the retinoblastoma protein (pRb), leading to the release of E2F transcription factors and aberrant cell cycle progression [5, 8, 11]. These proteins are constitutively expressed in HPV-transformed cells but are absent in normal tissues, making them highly specific therapeutic targets [12, 18]. Therapeutic strategies targeting these oncoproteins include DNA and peptide vaccines (e.g., VGX-3100, ISA101) designed to elicit a robust E6/E7-specific T-cell response, as well as adoptive cell therapies using T cells engineered with E6- or E7-specific T-cell receptors (TCRs) [1, 12, 14]. These interventions aim to overcome the immune evasion mechanisms of HPV-positive tumors and induce a cytotoxic response capable of eradicating malignant cells [17, 23]. Small molecule inhibitors are also under investigation to directly block the oncogenic interactions of E6 and E7 with host regulatory proteins [4, 9]. Clinical success in targeting these proteins depends on the sustained expression of the oncogenes throughout disease progression and the ability to generate long-lived, antigen-specific T-cell immunity [1, 21].

Other names

HPV16 E6HPV16 E7E6 oncoproteinE7 oncoproteinHPV-16 early proteins 6 and 7HPV-16 E6/E7 antigens

Therapeutic vaccines and adoptive T-cell therapies target these oncoproteins to induce or provide a cytotoxic T-cell response that recognizes and kills HPV-16-infected malignant cells. Small molecule inhibitors are also being explored to block the interaction of E6 with p53 and E7 with pRb.