An essential initial step in cancer cell invasion is the interaction of tumour cells with extracellular matrix (ECM) components and basement membranes, specifically the degradation of the ECM by MMPs, such as MMP‐3, proteolytically cleaved, and activated by MMP‐2, MMP‐3, MMP‐13 and plasmin, which facilitates tumour cell dissemination 14, 25, 27. This evidence concerns the gene PLG and cancer.