In pancreatic ductal adenocarcinoma, the FoxP3 expression was demonstrated in pancreatic cancer cells with tumor-infiltrating Tregs through the FoxP3/C-C motif chemokine ligand 5 (CCL5)/C-C motif chemokine receptor 5 (CCR5) pathway [27]. The gene discussed is FOXP3; the disease is pancreatic ductal adenocarcinoma.