MMP14 and glioma: It has been proposed that macrophages/microglia directly affect glioma cell migration through the ECM by secreting MMPs and that they indirectly affect it by promoting the activation of pro-MMP secreted in the microenvironment by glioma cells by means of membrane-type metalloproteases (MT-MMP), which has been proven to be overexpressed in tumor-associated microglia.