Fig. 1: Overexpression of IL-17RB at invasive tumor margins is correlated to poor prognosis.

A Representative IHC images of PanCK (red signal), IL-17RB (green signal), and Hoechst 33342 (blue signal) expression in FFPE samples of PDAC patients. PanCK (Pan-Cytokeratin) is an epithelial marker to indicate tumor cells. Scale bar, 25 μm. B H score of IL-17RB expression levels in regions with 0–20 μm and 20–40 μm distance from the tumor–stromal interface in PDAC patients (n = 29). **, P < 0.01 (paired t-test). C, D Representative IHC images (G) and H scores (H) of IL-17RB expression in regions of invasive and noninvasive tumors. The brown signal denotes IL-17RB expression. Scale bar, 50 μm. Each dot represents the datum from one high-power field (n = 50). E, F Kaplan–Meier analysis of progression-free survival (I) and overall survival (J) in regions with 0–20 μm distance from the tumor (P = 0.046 and P = 0.053, separately, Log-rank test). IL-17RB expression levels were scored by 0 (no staining), 1+ ( < 10% among cancer cells), 2+ (10 to 50% among cancer cells, and 3+ ( ≥ 50% among cancer cells). For statistical analyses, the score of 0 and 1+ was combined as the low expression group, and the score of 2+ and 3+ was combined as the high expression group. Blue line, IL-17RB low in 0–20 μm, n = 29; Red line, IL-17RB high in 0–20 μm, n = 15. Values are expressed as mean ± SD. *, P < 0.05; **, P < 0.01; ****, P < 0.0001 (two-tailed Student’s t-test).