Journal: Molecular Therapy Oncolytics

Article Title: Oncolytic herpes virus G47Δ works synergistically with CTLA-4 inhibition via dynamic intratumoral immune modulation

doi: 10.1016/j.omto.2021.05.004

Figure Lengend Snippet: Efficacy of G47Δ in combination with CTLA-4 or PD-1 inhibition in a murine subcutaneous AKR tumor model (A−D) Effects of G47Δ or CTLA-4 inhibition, either alone or in combination, on tumor growth in the murine subcutaneous AKR tumor model. (A) Experimental design. C57BL/6 mice harboring unilateral subcutaneous AKR tumors were given intratumoral injections with G47Δ (5 × 10 6 PFUs on days 0 and 3) or mock in combination with intraperitoneal injections with the anti-CTLA-4 antibody (25 μg on days 0, 3, and 6) as indicated. (B) Delayed tumor growth was observed with either G47Δ (p < 0.05) or CTLA-4 inhibition (p < 0.01) alone, but the combination treatment was associated with a significant decrease in tumor growth compared with each monotherapy (versus G47Δ, p < 0.001; versus αCTLA-4, p < 0.01). The results are presented as the mean ± SEM (n = 8 per group). (C) Individual tumor growth curves of AKR tumors. The combination therapy achieved a cure in 5/8 animals. (D) Kaplan-Meier survival curves. The combination therapy resulted in significantly prolonged survival (p < 0.001 versus control; G47Δ, p < 0.01 versus αCTLA-4). (E−H) Efficacies of G47Δ and PD-1 inhibition, either alone or in combination, in the murine subcutaneous AKR tumor model. (E) Experimental design. C57BL/6 mice harboring subcutaneous AKR tumors were treated with G47Δ (5 × 10 6 PFUs) or mock together with intraperitoneal injections with the anti-PD-1 antibody (100 μg) as indicated. (F) Tumor growth was significantly inhibited by the anti-PD-1 antibody alone (versus control, p < 0.001). The efficacy of G47Δ combined with systemic PD-1 inhibition was equivalent to that of PD-1 inhibition alone. The results are presented as the mean ± SEM (n = 7 per group). (G) Individual tumor growth curves. The combination therapy did not yield a cure. (H) Kaplan-Meier survival curves. One-way ANOVA followed by Dunnett’s test was used for the comparisons of tumor growth. For survival analysis, the log-rank test followed by Holm’s sequential Bonferroni corrections was used to determine statistical significance (∗p < 0.05; ∗∗p < 0.01; ∗∗∗p < 0.001; ns, not significant).

Article Snippet: Hepa1-6, a murine hepatoma cell line derived from a C57BL/6 mouse, was obtained from Japanese Collection of Research Bioresources (Osaka, Japan).

Techniques: Inhibition

Journal: Molecular Therapy Oncolytics

Article Title: Oncolytic herpes virus G47Δ works synergistically with CTLA-4 inhibition via dynamic intratumoral immune modulation

doi: 10.1016/j.omto.2021.05.004

Figure Lengend Snippet: Tumor-infiltrating lymphocytes in subcutaneous AKR tumors treated with the combination of G47Δ and CTLA-4 inhibition C57BL/6 mice harboring subcutaneous AKR tumors were treated according to the schedule shown in Figure 2 A. Tumor-infiltrating immune cells were analyzed by flow cytometry 7 days after the initial treatments. Comparisons of absolute numbers of (A) CD3 cells, (B) CD4 + T cells, (C) CD8 + T cells, and (D) Tregs (CD4 + Foxp3 + ) per gram of tumor tissue. (E) The percentage of Tregs, gated on CD4 + T cells. (F) The ratio of CD8 + T cells to Tregs. (G) The percentage of CD3, CD8 + , CD4 + , and Tregs gated on CD45 cells. Results are representative of two independent experiments with 7 animals per group, and bars represent the SEM. One-way ANOVA followed by Dunnett’s test was used to determine statistical significance (∗p < 0.05; ∗∗p < 0.01; ∗∗∗p < 0.001; ns, not significant).

Article Snippet: Hepa1-6, a murine hepatoma cell line derived from a C57BL/6 mouse, was obtained from Japanese Collection of Research Bioresources (Osaka, Japan).

Techniques: Inhibition, Flow Cytometry

Journal: Molecular Therapy Oncolytics

Article Title: Oncolytic herpes virus G47Δ works synergistically with CTLA-4 inhibition via dynamic intratumoral immune modulation

doi: 10.1016/j.omto.2021.05.004

Figure Lengend Snippet: Intratumoral immune-related gene-expression changes in subcutaneous AKR tumors 7 days after the initial treatments Gene expression analyses from AKR tumors, focusing on selected mRNAs related to inflammation, lymphocytes, activation markers, exhaustion signatures, and apoptosis. C57BL/6 mice harboring subcutaneous AKR tumors were treated with intratumoral inoculations with G47Δ (5 × 10 6 PFUs) and intraperitoneal injections with an anti-CTLA-4 antibody (25 μg). The tumor tissues were harvested 7 days after the initial treatments, total RNA was extracted, cDNA was reverse transcribed, and gene expression analysis was performed using qPCR analysis. The details of the gene symbols are presented in . The fold change in expression of the indicated genes (A) with G47Δ treatment over control, (B) with CTLA-4 inhibition over control, (C) with the combination therapy over control, and (D) the combination therapy over CTLA-4 inhibition. The bar represents mean fold change + SEM (n = 6). The yellow bars represent mRNAs that were significantly upregulated (p < 0.05, fold change ≥ 2) as compared with the reference group. The blue bars show mRNAs that were significantly downregulated (p < 0.05, fold change < 0.5) as compared with the reference group. The expression data were normalized to the geometric mean of three housekeeping genes ( Actb , Gapdh , and Hprt1 ). One-way ANOVA followed by Dunnett’s test was used to determine statistical significance. All experiments were performed twice, with six samples for each group.

Article Snippet: Hepa1-6, a murine hepatoma cell line derived from a C57BL/6 mouse, was obtained from Japanese Collection of Research Bioresources (Osaka, Japan).

Techniques: Expressing, Activation Assay, Inhibition