Huang et al. demonstrated that angiopoietin 2 (Angpt2), MMP3, and MMP10 expressed by melanoma cells increase vascular instability in the lungs, and knock down of these genes significantly decreases the ability of MDA-MB-231 breast cancer cells to metastasize (Huang et al., 2009) (Figure 2C). The gene discussed is ANGPT2; the disease is breast carcinoma.