The levels of uPAR and CXCR4 increase also in haematological malignancies; their expression in acute myeloid leukaemia (AML) varies according to the subtype, with lower expression in undifferentiated (M0) and higher expression in myelomonocytic (M4/5) AML 21,22,25. The gene discussed is CXCR4; the disease is acute myeloid leukemia.