CXCR4 and neoplasm: Interestingly, the CXCR4 antagonist Plerixafor (also known as AMD3100) is already Food and Drugs Administration-approved for stem cell mobilization in several tumors, including non-Hodgkin’s lymphoma and multiple myeloma (36, 37) and its systemic administration has been reported to inhibit growth of intracranial glioblastoma and medulloblastoma xenografts by increasing apoptosis and decreasing the proliferation of tumor cells (38).