[Flow cytometric techniques for measurement of proliferating cell nuclear antigen (PCNA)]

Flow cytometric techniques have been developed for measurement of proliferating cell nuclear antigen (PCNA), which allows studies on the proliferative capacity of cells and tissues. PCNA-DNA dual staining procedures, for both fixed and unfixed cells, and analytical method by FCM are presented. We recommend performing either the fixed or unfixed method. Our studies using the MCF7 human breast adenocarcinoma cell line and the A549 human lung squamous cell carcinoma cell line, in the exponential growth phase, revealed that both ethanol and acetone were satisfactory fixatives, in contrast to methanol and paraformaldehyde, and PI with a concentration of 25 micrograms/ml was most suitable compared with 50 and 100 micrograms/ml.