Abstract
Transforming growth factor-β (TGF-β) has been shown to induce apoptosis on normal hepatocytes and hepatoma cells both in vitro and in vivo. However, how the TGF-β induces apoptosis is still not clear. We examined the expression of anti-apoptosis proteins and sensitivity to TGF-β in three well differentiated human hepatoma cell lines. Two TGF-β sensitive cell lines Hep3B and HuH7 totally lacked Bcl-2. In contrast, the TGF-β resistant HepG2 cells expressed a substantial amount of Bcl-2. All three cell lines expressed equal amounts of Bcl-X(L), Bcl-X(s) and Bax. Overexpression of Bcl-2 in Hep3B and HuH7 cells protected them from TGF-β-induced apoptosis. TGF-β treatment increased intracellular peroxide production and suppressed the expression of glutathione-S-transferase in the Hep3B cells, and these effects were partially suppressed by the overexpression of Bcl-2. These results suggest that Bcl-2 may protect cell from TGF-β-F-induced apoptosis by interfering TGF-β generated signals leading to induce reactive oxygen species production.
Original language | English |
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Pages (from-to) | 185-191 |
Number of pages | 7 |
Journal | Journal of Biomedical Science |
Volume | 5 |
Issue number | 3 |
DOIs | |
State | Published - 1998 |
Externally published | Yes |
Keywords
- Antioxidative enzyme
- Apoptosis
- Bcl-2
- Reactive oxygen species
- TGF-β