MMP9 and cancer: Moreover, loss of Nrf1α also up-regulated transcriptional (and translational) expression of genes encoding matrix metallopeptidase 9 (MMP9) and membrane-type MMP17 in Nrf1α−/− cells (Figs 12c and 13b8); both were hence postulated to increase the breakdown of both extracellular matrix proteins (and pro-proteins) between cells insomuch as to induce cancer cell growth, invasion and metastasis, as described by79.