We focused on miR-146a, which can directly target CXCR4 and is strongly involved both in myelopoiesis and in acute myeloid leukaemia 37–40; interestingly, in melanoma cells, miR-146a targets the heterogeneous nuclear ribonucleoprotein C1/C2 (hnRNPC), a mRNA-binding protein which, in turn, is able to regulate the expression of uPA and its receptor 54,55. The gene discussed is PLAU; the disease is melanoma.