Caucasian-American extracellular matrix molecules (ECM) enhances metastasis to lung. (a) Number of animals positive for lung metastasis per animals injected. (b) Ethidium bromide stained gel of PCR products; RNA was analyzed by quantitative real-time PCR for lung metastasis using human-specific primers to β2 microglobulin. C = control human cDNA; L = mouse lung cDNA; NTC = no template control. (c) Representative hematoxylin and eosin (H&E)-stained mouse lungs with human breast cancer cell metastasis. (d) Immunohistochemical detection of metastasized cells with the human-specific antibody COXIV (left panels) or corresponding negative controls (right panels) in mouse lung. Scale bar = 50 μM. AA = African-American, CAU = Caucasian-American.