MMP12 and neoplasm: MMP12 is a member of the matrix metalloproteinase (MMP) family, whose members are well known for their essential roles in tumor invasiveness and multidrug resistance.34 Interestingly, a recently study pointed out that knocking out MMP12 caused the accumulation of macrophages in the TME,35 indicating that knocking out MMP12 may enhance chemoradiotherapy resistance in a macrophage-mediated way.