Expression of the proliferation marker Ki67 and the apoptotic marker M30 in CTCs of patients with early breast cancer. (A) Representative image of a CTC stained positive for the proliferation marker Ki67 along with PBMCs. (B) Representative image of a CTC stained positive for the apoptotic marker M30. Cytospins were triple stained with pancytokeratin rabbit antibody/secondary anti-rabbit Alexa Fluor 555 (orange), anti-Ki67 mouse antibody/secondary anti-mouse Alexa 633 (red) and M30 mouse FITC-conjugated antibody (green). Cell nuclei were stained with DAPI (blue). Images were taken by ARIOL system (X60). ARIOL system, automated image analysis system; CTCs, circulating tumor cells; DAPI, 4’,6-diamidino-2-phenylindole; FITC, fluorescein isothiocyanate; PBMCs, peripheral blood mononuclear cells.