A 35-year-old woman is diagnosed with cervical intraepithelial neoplasia grade 3 (CIN 3) caused by high-risk HPV types. Which viral oncoproteins are primarily responsible for malignant transformation by degrading p53 and retinoblastoma protein respectively?
- A E1 and E2
- B E6 and E7 ✓
- C L1 and L2
- D E4 and E5
Correct answer: B. E6 and E7
Explanation
High-risk HPV types (16, 18) produce E6 and E7 oncoproteins. E6 binds and degrades p53 via ubiquitination, while E7 binds and inactivates the retinoblastoma (Rb) protein, releasing E2F transcription factors. This disrupts cell cycle control and leads to malignant transformation. L1 and L2 are capsid proteins. E1 and E2 are involved in viral replication.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.