Alkaline phosphatase as a marker of transformation in adult mouse bladder epithelium after in vitro exposure to 7,12-dimethylbenz(a)anthracene.

Abstract Loss of alkaline phosphatase from bladder epithelium has been suggested as a specific preneoplastic change induced by chemical carcinogens in rats (Stiller and Rauscher 1971; Kunze and Schauer 1971; Kunze et al. 1975), and mice (Highman et al. 1975). Using an in vitro bladder epithelial cell transformation system established by treating primary cultures of mouse bladder epithelium from young adult and old donors with 7,12-dimethylbenz-(a) anthracene (DMBA) (Summerhayes and Franks in press) and electron microscope cytochemistry, the localisation of alkaline phosphatase was compared in normal mouse bladder, in epithelial cell cultures before and after transformation with DMBA and in tumours derived from implants of these cells in syngeneic mice.