Effects of C/EBPβ knock-down on EBV lytic gene expression and replication by bortezomib. C/EBPβ knock-down was performed in EBV+ Akata cells using an inducible vector in which the shRNAmir is only expressed in the presence of doxycycline (DOX). To induce shRNAmir expression, 1 μg/mL doxycycline was added to cells for 72 hours. Cells were treated with 20nM bortezomib (BZ) and harvested after 24 hours. RNA was isolated and subjected to real-time qPCR with primers for C/EBPβ (A) and ZTA (B). Primers to β-actin were used as an internal control. (C) Nuclear protein extracts were prepared and subjected to Western blot analysis. Blots were probed for C/EBPβ and ZTA. Blots were also probed for β-actin as a loading control. (D) Viral DNA was isolated and EBV viral load was measured using real-time PCR. Primers to the EBV BamW region were used to quantify EBV copy number. Primers to β-actin were used as an internal control. Error bars indicate SEM.