Figure 1.

HDAC Inhibition Increased JAM-1 Levels and Enhanced Reolysin Replication

The expression of the reovirus entry receptor JAM-1 and Reolysin (Reo) replication was assessed following administration of AR-42 (10 μM) or SAHA (20 μM) followed by Reolysin (10 MOI) for the indicated time point on SCC74-A (human) or MTE (murine) squamous carcinoma cell lines. (A) Flow cytometric analysis of SCC74-A (left) and MTE (right) JAM-1 cell surface expression following AR-42 or SAHA and/or Reolysin for 48 hr. Data shown are the mean fluorescence intensity (MFI) of cells, with n ≥ 2 per group ± SD. (B) Human red fluorescent protein (RFP)-expressing SCC74-A cells were assayed for the Reolysin capsid protein (green) following Reolysin plus AR-42 or SAHA treatment for 48 hr followed by immunohistochemistry. (C) SCC-74A cells were treated with Reolysin plus AR-42 or SAHA and supernatants were analyzed for reovirus replication using L929 cells using crystal violet staining in a standard plaque-forming unit (PFU) assay after 7 days. Representative images (left) of clear plaques obtained and quantification (right) of reovirus titers. *p < 0.001 (differences of combination-treated cells versus all other treatment groups). Data are representative of at least three independent experiments.