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Sirt3, mitochondrial ROS, ageing, and carcinogenesis
Seong-Hoon Park1, Ozkan Ozden, Haiyan Jiang
1Department of Cancer Biology, Pediatrics, and Radiation Oncology, Vanderbilt University Medical Center, Nashville, TN 37232, USA; E-Mails: romad96@gmail.com (S.-H.P.); ozkan.ozden@vanderbilt.edu (O.O.); haiyan.jiang@vanderbilt.edu (H.J.); yong.cha@vanderbilt.edu (Y.I.C.); daniel.pennington@vanderbilt.edu (J.D.P.); david.gius@vanderbilt.edu (D.G.).
International Journal of Molecular Sciences
|October 22, 2011
Summary
Cancer risk increases with age, linked to mitochondrial function. Sirtuin 3 (SIRT3) acts as a mitochondrial tumor suppressor, potentially impacting aging and breast cancer by regulating reactive oxygen species (ROS).
Area of Science:
- Gerontology and Cancer Etiology
- Mitochondrial Biology and Metabolism
Background:
- Malignancy rates rise exponentially with age, suggesting a link between aging and cancer mechanisms.
- Mitochondrial dysfunction, indicated by increased reactive oxygen species (ROS), is common in both aging and cancer.
Purpose of the Study:
- To explore the hypothesis that Sirtuin 3 (SIRT3) functions as a mitochondrial fidelity protein.
- To investigate SIRT3's role in modulating ROS metabolism, thereby influencing aging and carcinogenesis.
- To review potential links between mitochondrial ROS, aging, and phenotypes supporting estrogen/progesterone receptor-positive breast cancer.
Main Methods:
- Review of existing literature on longevity genes, Sirtuins, mitochondrial metabolism, and cancer.
- Analysis of the proposed function of SIRT3 as a mitochondrial tumor suppressor.
- Examination of the relationship between mitochondrial ROS/superoxide levels and carcinogenesis.
Main Results:
- Sirtuin proteins, particularly mitochondrial ones, are implicated in longevity and carcinogenesis.
- SIRT3 is identified as a mitochondrial-localized tumor suppressor.
- Modulation of ROS metabolism by SIRT3 is hypothesized to govern aging and cancer.
Conclusions:
- SIRT3 plays a critical role in maintaining mitochondrial integrity and function.
- SIRT3's tumor-suppressive activity is linked to its regulation of mitochondrial ROS.
- Understanding SIRT3's function may reveal new therapeutic targets for age-related diseases and breast cancer.
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