Fig 2.

VPA cotherapy attenuates the inflammatory transcriptome following oHSV therapy. (a and b) Human U87dEGFR cells (10⁵) were implanted intracranially into athymic mice brains and allowed to grow for 9 days. rQNestin34.5 (10⁴ PFU/3 μl vehicle) was then stereotactically inoculated, using the same coordinates. For VPA-treated mice, two VPA treatments were performed at 12-h intervals the day before oHSV inoculation. At 24 (a) or 72 (b) h later, mice were sacrificed for mRNA isolation of the tumor-bearing hemisphere. Following mRNA conversion to cDNA, the expression of 84 mouse inflammatory genes was analyzed by quantitative RT-PCR and presented as a volcano plot of VPA-induced changes in expression of each inflammatory cytokine and receptor. This plot arranges genes along dimensions of biologic and statistical significance. The x axis indicates the log₂ fold difference in gene expression for tumor tissue treated with VPA plus oHSV versus oHSV alone, and the y axis indicates P values obtained from the gene-specific t test on a negative log scale. The vertical line indicates no change relative to the control. The horizontal line indicates the threshold for a P value of 0.05 for the t test. Each point represents the mean value of the change in expression of an individual chemokine or chemokine receptor gene in tumors treated with VPA plus oHSV relative to tumors treated with oHSV alone. (c and d) Athymic mice were implanted with tumor, treated with VPA, and inoculated with rQNestin34.5 as described for panel a. Mice were sacrificed 24 h later for mRNA isolation and then cDNA synthesis or for protein extraction of the tumor-bearing hemisphere. The expression of IFN-γ was evaluated by real-time PCR (c) or ELISA (d), and two-sample t tests with Bonferroni adjustments were used to compare fold differences in expression levels. *, P < 0.05; **, P < 0.01; ***, P < 0.001. Error bars represent ± standard deviation.