[Study of flow cytometric bromodeoxyuridine (BrdU)/DNA analysis using human solid tumors]

In spite of the development of a staining principle and the method for simultaneous flow cytometric bromodeoxyuridine (BrdU)/DNA analysis, this technic was seldom used clinically, because, it can not be applied for the study of solid tumors. In this paper, we described a new method to overcome this problem by combining proteolytic enzyme digestion with previously reported immunofluorescent procedure. The difficulty of two-color analysis in solid tumors using previously reported method came from the non-specific staining of resulted cells which have Fc receptors on each cell surface and hence the gaps between S- and G1- or G2M-phase were unclear. By combining proteolytic enzyme digestion, the normal cell population can be excluded easily and the gaps between these phases be clearly distinguished, therefore the results obtained by this new method seemed to be more precise. This new method can be applied for solid tumor studies and the development for clinical application is expected.