Interestingly, numerous chemokines and associated receptors, including CXCL12 and CXCR4, have been shown to exert a key role in mediating the communication between cancer cells and nonmalignant stromal cells, ultimately favoring the establishment of a permissive microenvironment for tumor development and progression [22, 30, 36]. The gene discussed is CXCL12; the disease is cancer.