PLAUR and neoplasm: Abdalla et al. (2011) engineered an iron oxide nanoparticle that targeted the drug noscapine (Nos) to tumors using urokinase plasminogen activator (uPA), a natural ligand for uPA receptor (uPAR) that is highly expressed by prostate cancer cells. The uPAR-targeted Nos-loaded iron oxide nanoparticles enhance the inhibitory effect of noscapine on prostate cancer cell growth and maintain their T2 MRI contrast effect upon internalization into tumor cells (Abdalla et al., 2011).