This process can affect through two mechanisms: first, by direct stimulation of SDF1a to cancer cells that will induce growth and motility to avoid apoptosis and, second, by influencing the microenvironment, among them, by attracting EPC that induces angiogenesis so that cancer cells can intravasate more easily (Asri et al., 2016). The gene discussed is CXCL12; the disease is cancer.