Fig. 4

Effects of combinatorial treatments on tumor growth. a Mice bearing 4 T1 orthotopic xenografts were injected intravenously with PDGFRβ Gint4.T aptamer (at day 0, 2, 4, 7 and 9) and intraperitoneally with anti-mPD-L1 mAb (at day 0, 4 and 9), alone and in combination. Mice treated with Scr aptamer were used as the control group (Ctrl). Tumor growth was monitored by calipers over time and experimental raw data (expressed as fold increase) were interpolated with no curve fitting or regression analysis. Treatment schedule is shown. Day 0 marks the start of treatments. ^# P < 0.05 relative to Ctrl; one-way ANOVA followed by Tukey’s multiple comparison test; ^* P < 0.05. b Mice body weight was measured at the indicated days and the mean weight of each group is shown. a-b The mean ± SEM (n = 5) were calculated for all the groups. c Shown are images from one representative tumor sample for each treatment group stained with Ki-67 antibody. Ki-67 proliferation index was calculated as percentage of Ki-67 positive cells/total cell count for 5 randomly selected 40 × microscopic fields considering the Ctrl-group as 100%. Magnification 40 ×, scale bar = 50 μm. d-e Left, lysates from recovered tumors were immunoblotted with the indicated antibodies. Equal loading was confirmed by immunoblot with anti-vinculin antibody. One representative tumor sample per group is shown. Molecular weights of indicated proteins are reported. Middle and Right, quantification of immunoblot analysis for p-Akt, p-ERK1/2, PDGFRβ and PD-L1 normalized to the loading control vinculin. Bars depict mean ± SD (five mice for each group). c-e ^#### P < 0.0001, ^### P < 0.001, ^## P < 0.01 relative to Ctrl;^** P < 0.01; ^* P < 0.05; one-way ANOVA followed by Tukey’s multiple comparison test