Mast cell-derived AREG enhances the immunosuppressive capacity of regulatory T (Treg) cells, except for AREG expressed by cancer cells in specific cases, which produce acquired resistance to anti-EGFR therapies (e.g., cetuximab), and sensitivity to cetuximab depends on high expression of both EREG and AREG [50, 51]. Here, EREG is linked to cancer.