PU-H71 inhibits NF-κB with minimal lytic reactivation. (A) Immunoblot analysis of BC3 cells treated with 2 µM PU-H71 at the indicated time points shows that vFLIP is eliminated by 48 hours, whereas there is no consistent decrease in vCyclin, LANA, or vIL-6, as determined by quantification of band intensity and normalized to β-actin and untreated control cells a time 0 (shown below each immunoblot lane). (B) Immunoblot analysis for the panel of viral genes indicated was done using additional PEL cell lines, treated with 2 μM PU-H71 for 24 hours. (C) JSC-1 cells were treated with TPA or PU-H71, and the percentages of green fluorescent protein (GFP)⁺ and RFP⁺ cells determined by counting under a fluorescent microscope. (D) Expression levels of latent (LANA, vFLIP, vIL-6) and lytic (ORF50, ORF59, and K8.1) transcripts was studied by quantitative reverse-transcription polymerase chain reaction analysis of extracts from BC3 cells treated with PU-H71 for the indicated time points. The experiment was performed 3 times in triplicate, and representative results are shown. A variable but global decrease of these transcripts was observed (for analysis of other cell lines, see supplemental Figure 7A). (E) Expression of lytic genes induced by TPA was inhibited by PU-H71, as shown after treatment with the compounds for 24 hours.