In vitro studies using pancreatic cancer cell lines have shown that the knockdown of uPA reduces cancer cell migration, invasion and viability (130).Multiple in vivo studies have shown that inhibiting uPA with antibodies, uPA-directed prodrugs or radioisotopes and small molecule inhibitors alone or in combination with other drugs can block cancer growth, invasion and metastasis in prostate and breast cancer (131–135). Here, PLAU is linked to breast cancer.