Figure 4.
Repeated intratumoral oHSV administration improved mice survival
(A) Using a modified Winn assay, cohorts of Balb/C mice were randomized into 3 cohorts and implanted with 1×105 DBT tumor cells that had been mock or oHSV infected (R3616 or C134) at an MOI of 1 for 1 h prior to implantation. One week later, the respective mice cohorts were saline or oHSV re-treated (1×107 PFU of R3616 or C134) and survival of mice was monitored. (B) DBT cells were either pretreated with Mitomycin C (Mito-C) or oHSV (R3616 or C134: MOI 1) before intracerebral implantation in Balb/C mice. Seven days later, the Mito-C tumor bearing cohort was treated with saline and the oHSV treated cohorts was re-treated with their respective oHSV (R3616 or C134 1×107 PFU). After 50d, an age matched DBT-naïve cohort and the long-term survivors (both oHSV-treated and Mito-C tumor implanted mice) were then challenged with 1×106 DBT tumors in flank and tumor growth monitored. Results show that C134 long-term survivors resist tumor re-challenge at a distant site better than naïve (***P = .0004, C134 vs. Naïve Mock) or tumor antigen experienced mice (**P = .0095: C134 vs. Mito-C) based upon one way ANOVA (Kruskal-Wallis with Dunn's correction for multiple comparisons).