Glucose-6-phosphatase activity in regenerating cholangiole cells and hepatoma cells

Histogenesis of hepatic cancer has been analysed by observing glycogen by PAS staining and the histochemically demonstrable G-6-Pase activity on the liver of rats fed with 3'-Me-DAB or 3'-Ni-DAB. By observations on normal hepatic tissue it has been revealed that these two reactions are specific to the cytoplasm of liver parenchymal cells. Observations on the liver from the early stage of dye feeding, up to 100 days, show a marked proliferation of cholangioles in 3'-Me-DAB feeding on polished rice but only a poor reaction of cholangioles in 3'-Me-DAB feeding with synthetic diet. After 15-16 weeks of 3'-Me-DAB feeding cancer develops, a great erpart of which is consisted of cholangiocellular carcinoma and a portion, hepatocellular carcinoma. Histochemical observations on G-6-Pase and glycogen reveal that regenerating cholangiole and adenomatous tissues seem to have poles, on one side, the cells differentiate to liver parenchymal cells and on the other side, they differentiate to bile duct cells. Cancers develop mainly from these regenerating adenomatous tissues and they develop to cholangiocellular cancer or to hepatocellular cancer. The histogenesis of the latter can be traced histochemically. In the cases fed with 3'-Ni-DAB, the activity of cholangiole cells and the development of adenomatous tissue are rather poor with the delayed cancer formation. However, in these cases the majority of cancers are of hepatocellular carcinoma and the developmental mode of hepatocellular cancer can easily be traced by the G-6-Pase activity.