IL4I1 and colorectal carcinoma: Most importantly, interleukin-4-induced-1 (IL4I1) and indoleamine 2 3-dioxygenase 1 (IDO1) are upregulated in subclonal ANK1 mutation CRC patients (Fig. 4D), which could inhibit T cell activation by inhibition of effector cell proliferation and immunoregulation mediated by Treg cells induction [25].