The Effect of Partial Hepatectomy and/or Splenectomy on the Appearance of Phenotypic Expressions of γ-Glutamyltranspeptidase and C-Myc Oncoprotein During Hepatocarcinogenesis in Rats

We examined the effect of partial hepatectomy (PH) and/or splenectomy (SPX) during diethyl-nitrosamine-induced hepatocarcinogenesis in rats by sequential, quantitative analysis of γ-glutamyl-transpeptidase (GGT)-positive hepatocellular foci. Immunohistochemical expression of c-myc protein which is known to be closely related to cellular proliferation was additionally investigated along with cellular glycogen-storage abnormality. GGT-positive foci increased in number in a group of PH compared with non-PH groups, but they were most pronounced in a group of PH plus SPX at the experimental weeks of 36. c-myc-positive foci, which first appeared in groups of PH and PH plus SPX at 24 weeks, were found to be restricted to glycogen-deficient foci; 81% of glycogen-deficient foci were c-myc positive. The data suggest that PH or PH plus SPX which is performed in the process of hepatocarcinogenesis has a potential to significant enhancement of the (pre-) neoplastic progression.