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: Overall survival in all 181 cases. This survival curve is based on the median values of preoperative serum levels of B7 family molecules in all 181 cases. The cases were divided into two groups at this level – high and low expression. P value was analyzed by log-rank test. The patients with higher preoperative serum levels of PD-L1 (A), B7-H4 (B) and VEGF (C) had poorer overall survival.