An in vitro model of human pancreas carcinogenesis: effects of nitroso compounds.

It has been possible to maintain adult human pancreas in organ culture in a chemically defined medium. Under these conditions, all cell types demonstrated at least a limited ability to proliferate. This in vitro model was employed to study the effects of three nitroso compounds, DMNA, MNU, and BHP, on adult human pancreas. The major effects of three nitroso compounds, DMNA, MNU, and BHP, on adult human pancreas. The major effects of these compounds in cytotoxicity, proliferation, and oncogenicity was evaluated morphologically. DMNA and MNU were both carcinogenic but with varying rapidity of induction. MNU produced greater necrosis but gave more rapid induction. BHP produced cytotoxicity sufficient to prevent any rating of its oncogenic potential. Morphologically malignant tissue were tested for growth potential in nude mice. All nude mice developed multiple subcutaneous tumor nodules within eight weeks after inoculation. The tumor nodules ranged morphologically from undifferentiated scirrhous carcinoma to well-differentiated papillary adenocarcinoma.