In consideration of the role of uPA/uPAR/plasmin system-mediated MMPs activation in tumour migration and invasion, we attempted to investigate the influence of MIF silencing and overexpressing on the levels of uPAR, a plasma membrane GPI-anchored protein, that binds with high-affinity and activates the serine protease uPA, thus regulating MMPs activity. The gene discussed is PLAUR; the disease is neoplasm.