Fig. 6

GDNPs inhibit melanoma tumor growth in vivo. a Schematic of the B16F10 melanoma model and GDNPs/vehicle treatment regimen. At the end of the experiments, mice were sacrificed, and the anticancer effects in each group were evaluated and compared (n = 8). b Tumor growth profiles in different treatment groups (n = 8). c Tumor weights at the end of the experiment were compared (n = 8). d Body weight changes in different treatment groups. Mouse body weight was normalized to that at the time of implantation (n = 8). e Flow cytometry analysis and quantification of M1 (CD86^hi) and M2 (CD206^hi) cell populations in TAMs at day 21 post-implantation (n = 5). Representative flow cytometry analysis and quantification of CD11b⁺ F4/80⁺ (TAM) cell populations in tumors at day 21 post-implantation; expression of CD206^hi (M2) and CD86^hi (M1) in CD11b⁺ F4/80⁺ cell populations. The histogram bars show the percentage and mean fluorescence intensity (MFI) change in each cell population (M2 and M1) in GDNP-treated groups compared to the PBS-treated controls. f Representative immunofluorescence staining for F4/80 (red), CD206 (green) and CD86 (blue) of B16F10 tumor sections obtained at 21 days post-implantation (Scale bar = 100 μm). g The number of positive cells in 10 randomly selected fields of view (FOV) were counted and quantified for 3 tumors per group. h The percentages of T cells and NK cells in total CD45⁺ TILs. i Quantification by flow cytometry of ratio of CD8⁺/Treg in CD45⁺ TILs in B16F10 tumors at day 14 with GDNPs treatment. j Tumor tissues were excised, fixed and sectioned. H&E staining of tumor tissues from each group was used to evaluate the death of tumor cells (Scale bar = 100/20 μm). k B16F10-bearing C57BL/6 mice were treated with GDNPs in the presence or absence of clodronate liposomes, which deplete macrophages (n = 5). Mice in the control group were treated with liposomes containing PBS. Immunofluorescence staining for F4/80 (red) and DAPI (blue) of tumor sections obtained 21 days post-implantation of cancer cells with and without GDNPs and/or clodronate liposome treatment (Scale bar = 100 μm). l Serial tumor volume measurements up to day 20 after tumor implantation in mice treated with GDNPs in the presence or absence of clodronate liposomes (n = 5). All results represent the mean ± SEM. Two-way ANOVA (b, d, l) and Student’s t test (c, e, g, h, i) were used to compare results of different experimental groups for statistically significant difference (*P < 0.05, **P < 0.01, ****P < 0.0001)