Serum VCAM-1 levels were observed to correlate with micro vessel density in breast cancer, suggesting that serum VCAM-1 is a surrogate angiogenesis marker.21 Furthermore, VEGF has been shown to upregulate VCAM-1 expression in endothelial cells.22,23 Additionally, there is an interaction between VCAM-1 and α4β1 integrin during angiogenesis. The gene discussed is VCAM1; the disease is breast cancer.