It has been described that stromal cells, from different tumors, are able to synthetize mRNA for diverse molecules, for example collagenase, matrix metalloproteases and proteases, such as plasmin, all responsible of the early stages of tumor growth through the degradation of the extracellular matrix components (ECM) that is one of the mechanisms that neoplastic cells use to invade the interstitial tissue [39]. Here, PLG is linked to neoplasm.