α‐SMA was a biomarker for cancer associated fibroblasts that contribute to tumor progression by promoting angiogenesis and remodeling the extracellular matrix.[28, 29] Tumor‐associated fibroblasts and macrophages (human CD68+ or mouse F4/80+) play a major role in the maintenance of immunosuppressive microenvironment in pancreatic cancer (Figure 2A,B).[30, 31] Particularly, the levels of CAFs in the tumor are negatively correlated with clinical outcomes of patients with PDA (Figure S1C, Supporting Information). Here, CD68 is linked to Patent ductus arteriosus.