Bellezza I, Grottelli S, Gatticchi L, Mierla AL, Minelli A. α-Tocopheryl succinate pre-treatment attenuates quinone toxicity in prostate cancer PC3 cells.
Gene 2014;
539:1-7. [PMID:
24530478 DOI:
10.1016/j.gene.2014.02.009]
[Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 02/03/2014] [Accepted: 02/06/2014] [Indexed: 12/18/2022]
Abstract
UNLABELLED
α-Tocopheryl succinate is one of the most effective analogues of vitamin E for inhibiting cell proliferation and inducing cell death in a variety of cancerous cell lines while sparing normal cells or tissues. αTocopheryl succinate inhibits oxidative phosphorylation at the level of mitochondrial complexes I and II, thus enhancing reactive oxygen species generation which, in turn, induces the expression of Nrf2-driven antioxidant/detoxifying genes. The cytoprotective role of Nrf2 downstream genes/proteins prompted us to investigate whether and how α-tocopheryl succinate increases resistance of PC3 prostate cancer cells to pro-oxidant damage. A 4h α-tocopheryl succinate pre-treatment increases glutathione intracellular content, indicating that the vitamin E derivative is capable of training the cells to react to an oxidative insult. We found that α-tocopheryl succinate pre-treatment does not enhance paraquat-/hydroquinone-induced cytotoxicity whereas it exhibits an additional/synergistic effect on H₂O₂₋/docetaxel-induced cytotoxicity. While glutathione and heme oxygenase-1 are not involved in α-tocopheryl succinate-induced adaptive response to paraquat,
NAD(P)H
quinone oxidoreductase seems to be responsible, at least in part, for the lack of the additional response. Silencing the gene and/or the inhibition of
NAD(P)H
quinone oxidoreductase activity counteracts the α-tocopheryl succinate-induced adaptive response. In conclusion, the adaptive response to α-tocopheryl succinate shows that the activation of Nrf2 can promote the survival of cancer cells in an unfavourable environment.
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