Figure 4.

3M‐052 antimetastatic effects require intact immunity. (a) NSG mice were injected with 1 × 10⁵ 4T1.2 cells into the 4th mammary fat pad, and palpable tumors were i.t. injected with vehicle or 3M‐052 on day 6 post‐inoculation. Primary tumors were resected on day 13 and were assessed for (b) weight (mg); (c) number of CD11b⁺Ly6G⁺ cells and macrophage phenotype; and (d) MHC‐I (H2‐K^d) expression of various cell types by flow cytometry. (e) Lungs were taken at endpoint for H&E staining to assess metastatic burden; tumor regions are denoted by dotted line and ‘T’ (4× and 20× magnification, scale bars = 200 µm, representative images shown). (f) Kaplan–Meier survival curve comparing metastasis‐free survival. MΦ: macrophage. MFI: mean fluorescence intensity. Data representative of one experiment. All data n = 5 mice/group except (e) n = 3 mice/group. Statistical analysis was performed by (b–d) the Student's two‐tailed t‐test and (f) the Mantel–Cox log‐rank test. Error bars are SEM. *P < 0.05; **P < 0.01; ***P < 0.001; and ****P < 0.0001.