Fig. 1: Expression levels of the Notch signal-related genes in diethylnitrosamine (DEN)-induced murine hepatocellular carcinoma (HCC).

a A macroscopic picture of liver tumors developed 10 months after the administration of DEN. Arrows indicate the tumors observed on the liver surface. b DEN-induced HCC tissues were analyzed by immunofluorescent double-staining with anti-Hes1 (green) and anti-Hnf4α (magenta) antibodies together with 4′,6-diamidino-2-phenylindole (DAPI) nuclear staining (blue). Scale bar, 50 μm. c, d Total RNA isolated from the non-tumorous region (NT) and HCC was subjected to quantitative reverse-transcription (RT)-PCR analysis to detect the expression levels of Hes1 (c), Delta-like 1 (Dll1), Delta-like 4 (Dll4), Jagged-1 (Jag1), and Jagged-2 (Jag2) (d). The values represent the mean ± standard deviation (SD) from five samples and are expressed relative to the mean value in NT (set as 1.0). e Correlations between the amounts of Hes1 mRNAs and Dll4 or Jag1 mRNAs were analyzed using DEN-induced HCC samples obtained from eight male mice.