Fig 3.

Inhibitors of cell cycle progression were tested for effects on the antiviral activity of compound PA25. (A) W12E cells were treated with 250 nM nocodazole (Noc; Sigma catalog no. M1404) with or without 1 μM PA25 (n = 6). (B) W12E cells were treated for 24 h with 2 mM hydroxyurea (HU) with or without 1 μM PA25. HU had a small effect on HPV16 episome levels that was not statistically significant. HU did not block PA25 activity. (C) Effects of 4 μM aphidicolin (Aph) on W12E cell episomes in the presence of increasing amounts of PA25 or 0.1% DMSO control for 48 h. **, aphidicolin versus DMSO control (n = 12 samples from 3 independent experiments); *, aphidicolin plus PA25 versus PA25 alone (n = 6); P = <0.01. (D) HPV18 and HPV31 genomes are also lost following aphidicolin treatment. HPV31 or HPV18 episome-maintaining cell lines were treated for 48 h with 4 μM aphidicolin and episomes quantified by real-time PCR (n = 6; *, P = <0.01).