Reconstitution of the malignant phenotype of genitourinary cancer in gradient culture

Summary The diagnosis of cancer is made on histologic examination by recognizing the characteristics of the malignant phenotype, i.e. abnormal cells in abnormal groupings, often in abnormal locations. Histophysiologic gradient culture reconstitutes conditions that meet the spatial imperatives of tissues in nature. A variety of carcinomas arise in the genitourinary system involving both glandular and stratified epithelium. To be considered here are the contrasting polarizations of proliferation of normal and neoplastic rat urothelium, the continuity of sheets of epithelium in nature, the poorly understood stable and unstable interepithelial boundaries, and the formation of organoid endocrinelike tissue in histophysiologic gradient culture of normal human amnion epithelium. This work was supported by research grant CA-14137 from the National Cancer Institute, Bethesda, MD, grant 1793 from the Council for Tobacco Research, and grants from the American Fund for Alternatives to Animal Research.