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Updated: Oct 1, 2026

Cell Type-specific Gene Expression Profiling in the Mouse Liver
10:06

Cell Type-specific Gene Expression Profiling in the Mouse Liver

Published on: September 17, 2019

Distinctive gene expression of receptor-type tyrosine kinase families during rat hepatocarcinogenesis

Hiroaki Kuroda1, Akira Ohtsuru, Mitsuru Futakuchi

  • 1Department of Surgery II, Nagasaki University School of Medicine, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan.

International Journal of Molecular Medicine
|April 17, 2002
PubMed

Insights

This study identifies key receptor tyrosine kinases (RTKs) involved in liver cancer development. Overexpression of c-Met, Tie-2, and Flk-1 in rat hepatoma suggests their critical roles in hepatocarcinogenesis.

Area of Science:

  • Hepatology
  • Molecular Biology
  • Cancer Research

Background:

  • Growth factor receptor tyrosine kinase (RTK) signaling is crucial for normal hepatocyte growth.
  • The specific RTKs involved in hepatocarcinogenesis remain largely undetermined.

Purpose of the Study:

  • To investigate the expression profiles of RTKs during various stages of chemically-induced rat liver carcinogenesis.
  • To identify specific RTKs that play significant roles in the development of hepatoma.

Main Methods:

  • Utilized homology cloning with degenerated primers to compare RTK gene expression in normal rat liver and diethylnitrosamine-induced hepatoma tissues.
  • Employed in situ hybridization, immunohistochemical staining, and RT-PCR to analyze cell-type-specific RTK expression during hepatocarcinogenesis.

Main Results:

  • Identified 23 different RTK genes, with Tie-2, c-Met, and Flk-1 being most abundant in hepatoma compared to normal liver.
  • Demonstrated overexpression of c-Met and Flk-1 in preneoplastic and neoplastic lesions.
  • Observed Tie-2 expression in endothelial cells and oval cells, with differential expression of its ligands (angiopoietin-1 and angiopoietin-2) in hepatoma.

Conclusions:

  • c-Met, Tie-2, and Flk-1 signaling pathways are implicated in distinct phases of chemically-induced hepatocarcinogenesis.
  • Altered RTK gene expression patterns may contribute to the epigenetic mechanisms underlying hepatoma formation.

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