CXCR4 and neoplasm: CXCL12 (SDF-1α)/CXCR4 signaling is upregulated in radiation-induced EndoMT in tumor vasculature where it is required for tumor-associated macrophage recruitment (Choi et al., 2018), and knockdown of either of CXCL12’s receptors, CXCR4 and CXCR7, disrupts angiogenic sprouting in vitro (Hultgren et al., 2020).