MRC1 and central nervous system cancer: Spatially, our data showed different preferences of glioma-associated macrophages for the perivascular (Mrc1/Cd206+ macrophages) and hypoxic (Msr1/Cd204+ macrophages) niche based on marker gene expression profiles, implying differential activation of tumor-supportive gene programs in the tumor microenvironment; a notion also supported by previous studies4,24,101.