Western blot analysis of CXCr4 protein expression in high CXCR4 expressing Ewing sarcoma cell line IARC-EW3, medium CXCR4 expressing breast cancer cell line MDA-MB-468 and low CXCR4 expressing Ewing cell line IARC-EW7 (supplementary results [10]) using two N-terminal antibodies (Ab2074 and NBP1–76867) and one C-terminal antibody (UMB2). Here, CXCR4 is linked to breast cancer.