[A study of progression in hepatocarcinogenesis using cell transplantation system].

It is important to distinguish a precancerous lesion and hepatocellular carcinoma (HCC) with diploidy or aneuploidy nuclear DNA pattern, not only in clinical cases but also in experimental carcinogenesis models. Using liver perfusion technique, we detected early HCC from persistent hyperplastic nodules (HN) which were induced in Wistar rats by intermittent 5-6 months administration of 2-acetylaminofluorene. This investigation was undertaken to assess both promotive and progressive effects of liver regeneration following partial hepatectomy (PH). Results are as follows: 1) Isolated hepatocytes of precancerous HN, which were transplanted into the spleen, didn't develop to HCC by 2 months after 70% PH of host liver. 2) Diced tissues of HCC, which were transplanted into the liver via portal vein, grew many metastasis in 10/10 by 7 weeks after PH, while 5/19 in control. 3) Nuclear DNA patterns of early HN-late HCC in rat liver were diploidy at the rate of more than 90% each. But it changed to aneuploidy, when inoculation of HCC for one month was repeated 7 times in the spleen.