Owing to their great anti-tumor and anti-metastatic potential, CXCR4 antagonists have been tested clinically in multiple cancers, such as acute myeloid leukemia (AML), glioblastoma (GBM), breast, pancreatic and prostate cancers [198], and the preliminary results are promising. The gene discussed is CXCR4; the disease is acute myeloid leukemia.