CXCL16 and cancer: Here we demonstrate that the C–X–C motif chemokine ligand 16 (CXCL16)/C–X–C chemokine receptor type 6 (CXCR6) axis plays a critical role in recruiting TNFR2+ Treg cells to MPE, with cancer-associated fibroblasts serving as the primary source of CXCL16.