Moreover, using a multimodal single-cell analysis of the tumor microenvironment, Guldner et al. identified a heterogeneous, but spatially defined CNS myeloid response during brain metastasis growth, mostly promoted by microglia with a typical signature in which the homeostatic markers CX3CR1 and TMEM119 are downregulated. The gene discussed is TMEM119; the disease is neoplasm.