Fig. 4: Upregulated sGpnmb expression is responsible for ICI resistance in RenCa tumor model.

a–d P0 (a) or P4 cells (b, c) were implanted subcutaneously (s.c.) into mice (n = 5) and treated with control, anti-Gpnmb (αGpnmb) or anti-PD1 (αPD1) mAb. Tumor volume is measured. Blue arrows show the date of blood drawn. P4 tumor weights in each treatment group were measured at the endpoint (c) (mean ± SEM, n = 5). d Blood samples collected from mice (b) were determined for sGPNMB and plotted against days after implantation. e Survival rate (%) of P4 tumor-bearing mice (n = 10) treated with control, anti-PD1 or anti-Gpnmb Ab, until day 60; p value compared to PD1 treatment group. f, g Total cells were prepared from Ab-treated tumors and sorted into CD45⁺ fraction in flow cytometry, followed by determination of % leukocyte subtype among CD45⁺ cells. Representative dot plots are shown, with % positivity (f). Data are summarized in a graph (g) (mean ± SEM, n = 5). h–j RenCa parental cells transfected with Tet-Off-controlled sGpnmb gene were implanted subcutaneously (s.c.) into mice treated with doxycycline (Dox). On day 6, all mice were sorted into two groups. Dox-continued and Dox-discontinued (PBS-injected) and treated with anti-PD1 or control (Ctrl) Ab (h). Tumor volume is measured (i). On day 24, tumors were excised and measured (j) (mean ± SEM, n = 5). Data shown are representative of at least two independent experiments. P values are compared to control group using two-way ANOVA.