In vitro and in vivo effects of G47Δ in murine carcinomas
(A) Cytopathic effects of G47Δ in vitro. Murine cancer cells were infected with G47Δ (AKR, HNM007, MOI of 0.1 [●] or 1 [○]; SCCVII, MOI of 0.01 [▲] or 0.1 [●]) or mock. Cell viability was expressed as a percentage of the mock-infected controls. G47Δ exhibited a good cytopathic effect in AKR and HNM007 cell lines at an MOI of 1.0 and in SCCVII at an MOI of 0.1. Data are presented as the mean of triplicates ± SD. (B) Virus yields of G47Δ in vitro. Murine cancer cells were infected with G47Δ at an MOI of 0.1, and recovered virus yields were determined at 24 and 48 h after infection. All murine cancer cell lines tested supported the replication of G47Δ to a certain extent. The results are presented as the mean of triplicates ± SD. (C) Four syngeneic murine subcutaneous tumor models (AKR [upper left], HNM007 [upper right], SCCVII [lower left], and B16-F10 [lower right]) were used. Established tumors, 5–6 mm in diameter, were inoculated with G47Δ (2 × 105 for SCCVII and 5 × 106 PFUs for others) or mock on days 0 and 3. The G47Δ treatment significantly inhibited the growth of subcutaneous tumors compared with the mock treatment in all models. The results are presented as the mean ± SEM (n = 7). One-way ANOVA followed by Dunnett’s test was used to determine statistical significance (∗p < 0.05; ∗∗p < 0.01; ∗∗∗p < 0.001).