HPV

Question 1

How does HPV infection predispose to cervical dysplasia and CIN?

Answer 1

Viral genome integration (in infection with HPV 16 or 18) can disrupt the E2 gene
Causes overexpression of E6 and E7 oncoproteins
E6 binds p53, leading to apoptosis resistance, loss of cell cycle arrest and therefore genomic instability (DNA damage goes unrepaired)
E7 binds Rb tumour suppressor, disrupting cell cycle arrest
p16 is increased to compensate but is not sufficient to prevent neoplastic effects