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Updated: Apr 19, 2026
06:54
Studying TGF-β Signaling and TGF-β-induced Epithelial-to-mesenchymal Transition in Breast Cancer and Normal Cells
Published on: October 27, 2020
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MAPK inhibitors differently modulate TGF-β/Smad signaling in HepG2 cells
1Department of Pharmacology and Institute of Natural Medicine, Anhui Medical University, Hefei, 230032, China.
Summary
Mitogen-activated protein kinase (MAPK) pathways crosstalk with TGF-β/Smad signaling, promoting liver cancer. Inhibiting JNK/p38 pathways suppressed hepatocellular carcinoma cell proliferation and invasion by blocking key Smad signaling components.
Area of Science:
- Cell Biology
- Molecular Biology
- Cancer Research
Background:
- Mitogen-activated protein kinase (MAPK) pathways are implicated in cellular processes.
- The interplay between MAPK and Transforming Growth Factor-beta (TGF-β)/Smad signaling is crucial in hepatocarcinogenesis.
- Understanding these crosstalk mechanisms is vital for developing targeted therapies for liver cancer.
Purpose of the Study:
- To investigate the crosstalk between MAPK and TGF-β/Smad signaling in hepatocarcinogenesis.
- To determine the role of specific MAPK pathways (JNK, p38, ERK) in liver cancer progression.
- To evaluate the effects of MAPK inhibitors on hepatocellular carcinoma (HCC) cell proliferation and invasion.
Main Methods:
- Hepatocellular carcinoma was induced in rats using diethylnitrosamine (DEN).
- HepG2 cells were treated with specific MAPK inhibitors (SP600125, SB203580, PD98059) to antagonize TGF-β1 signaling.
- Cell proliferation, invasion, protein expression (Smad2/3, Smad4, Smad7), and PAI-1 mRNA transcription were assessed.
Main Results:
- MAPK inhibitors suppressed hepatocellular carcinoma cell invasion.
- SP600125 and SB203580 inhibited cell proliferation, while PD98059 did not.
- SP600125 and SB203580 blocked specific Smad phosphorylation and Smad2/3/4 complex formation, restoring Smad7 expression.
- All MAPK inhibitors repressed PAI-1 mRNA transcription, with PD98059's mechanism remaining unclear.
Conclusions:
- MAPK pathways, particularly JNK and p38, are key mediators in TGF-β1-induced hepatocarcinogenesis.
- Targeting JNK and p38 signaling effectively inhibits HCC cell proliferation and invasion.
- These findings highlight the therapeutic potential of MAPK inhibitors in liver cancer treatment.
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