CXCL12 and acute myeloid leukemia: found that patients with increased CXCR4 expression in the CD34+ subset of cells had significantly reduced chances of survival and a higher probability of relapse, suggesting that the Stromal Cell-Derived Factor-1(SDF-1)/CXCR4 axis may influence responsiveness to therapy and contribute to an unfavorable prognosis of AML (27).