Fig 2: Relationship between serum B7 family molecules. Spearman rank correlation between the preoperative serum levels of VEGF and B7-H4/PD-L1 in all 171 cases (A and C) and in 83 metastatic (M1) cases at nephrectomy (B and D). The preoperative serum levels of B7-H4 and PD-1 were positively associated with those of VEGF in all case and in M1 cases.

Fig 3: Preoperative serum levels between healthy volunteers and RCC patients. Preoperative serum levels of VEGF (A), B7-H4 (B) and PD-L1 (C) were higher in RCC patients than those in healthy volunteers, whereas those of PD-1 (D) were not. The median value is the central line, the box is the interquartile range, the bars are the full range, and the points are the outliers. Bold circled P values were obtained by comparing the two groups with the Mann–Whitney U-test.

Fig 4: The concentrations of sPD-1 and sPD-L1 in plasma and the concentrations of PD-1 and PD-L1 in kidney homogenate (A). Correlation was shown between sPD-1 in plasma and PD-1 in kidney homogenate (r = 0.774, p<0.001) (B), between sPD-L1 in plasma and PD-L1 in kidney homogenate (r = 0.881 p<0.001) (B) using Spearman’s test.

Fig 5: Spearman rank correlation between sIL-2R and Akt in the primary tumors and PD-L1. Spearman rank correlation between the preoperative serum sIL-2R level and the expression levels of phosphorylated Akt(Ser-473) in the primary tumors (a), and preoperative serum PD-L1 level (b)