ANXA5 and leukemia: The effects of melittin on CCRF CEM and K-562 cells apoptosis were investigated by using the flow cytometry method using simultaneous staining with propidium iodide and Annexin V. By using the double-staining flow cytometry method, we observed that incubation of leukaemia cells with melittin results in a dose- and time-dependent increase of Annexin V fluorescence which was related to the apoptosis process of cells.