In addition, CXCL11 is capable of promoting immunosuppressive indoleamine 2,3-dioxygenase (IDO) expression in human basal cell carcinoma and enhancing keratinocyte proliferation, thus potentially reducing the anti-tumor activity of any infiltrating CXCR3+ effector T cells (138, 139). Here, CXCR3 is linked to basal cell carcinoma.