Figure 4.

Tumor‐associated macrophages are inversely correlated with pancreatic ductal adenocarcinoma (PDAC) cells harboring high 15‐hydroxyprostaglandin dehydrogenase (15‐PGDH) expression. A,B, Representative immunohistochemical (IHC) staining of 15‐PGDH (upper panel) and CD163 (lower panel) expression in high 15‐PGDH (A) and low 15‐PGDH (B) serial PDAC specimens. Scale bar = 200 μm. C, Graph showing Pearson's correlation between the expression of 15‐PGDH and the number of CD163‐positive cells in 107 PDAC patients. D, Schematic representation of the findings of this study. IL‐1βR, interleukin‐1β receptor