Since, activation of MMPs by plasminogen occurs through uPA-dependent plasmin generation (Ramos-DeSimone et al, 1999), it can be suggested that enhanced expression of uPAR is critical for sustaining basal level of activated Erk requisite for the secretion of pro-MMPs and plasminogen-mediated activation of the proteinases in colon cancer cells. This evidence concerns the gene PLAUR and malignant colon neoplasm.