CXCR4 and cancer: Among the chemokines, CXCL12, also known as stromal cell derived factor-1 (SDF-1), and its cognate receptor CXCR4 have been involved in cancer metastasis of several cancers where the CXCL12-CXCR4 axis is known to modulate phenomena such as chemotaxis, migration, proliferation, and angiogenesis [11, 12].