The lag time observed in plasmin generation by HDMVEC-surface bound tPA, about 20–30 min, is similar to that described for cerebral microvascular endothelial cells (Semov et al., 2005), but much longer than for pancreatic or breast cancer cells (Diaz et al., 2004; Sharma et al., 2010). The gene discussed is PLG; the disease is breast cancer.