PF4V1 and neoplasm: CXCL4L1 and CXCL10 are able to activate tumor cell-bound CXCR3-A, while CXCL9 and CXCL11 mainly act via the immune system45, 46 CXCR3-B, as previously mentioned, seems to be present in the tumor vasculature and has mainly an inhibitory effect.