MMP2 and lung cancer: MMP2 is directly activated by MT1-MMP, functioning in most cases as its effector, as is the case in invasion of GSCs, and it has been previously shown to protect lung cancer cells from radiation.31 However, in our system, MMP2 depletion did not affect the response to radiation in either GSC line (Supplementary Figure 7), nor did it increase DNA damage, alone or after radiation, as indicated by unchanged γH2AX foci and tail moment from a comet assay (Supplementary Figure 16F–I), suggesting MT1-MMP controls DNA damage responses (DDR) independently of MMP2.