Development of screening systems for drugs against human papillomavirus-associated cervical cancer: based on E6-E6AP binding.

Human papillomavirus (HPV) E6 protein forms a ternary complex with the cell-cycle regulator p53 and the E6-associated protein (E6AP) known as an E3 ubiquitin protein ligase, leading to the degradation of p53 via the ubiquitination pathway. As an attempt to employ interaction between HPV viral oncogene E6 and a cellular protein E6AP for in vitro screening system of drugs against HPV infection, we primarily investigated the E6AP-E6 binding through pull down assay and enzyme-linked immunosorbent assay (ELISA). E6AP immobilized on the resin produced specifically complexes with bacterially expressed E6 in a dose-dependent manner, as determined by immunoblot analysis. This result was collinear with that shown in ELISA, which is a useful system for mass-screening potential drugs with rapidity and cheapness. Screening system based on the interaction between E6AP and E6 may be a promising system in the development of drugs against cervical cancer caused by HPV infection.