51
|
Aggarwal BB, Sundaram C, Prasad S, Kannappan R. Tocotrienols, the vitamin E of the 21st century: its potential against cancer and other chronic diseases. Biochem Pharmacol 2010; 80:1613-31. [PMID: 20696139 DOI: 10.1016/j.bcp.2010.07.043] [Citation(s) in RCA: 341] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2010] [Revised: 07/12/2010] [Accepted: 07/27/2010] [Indexed: 02/07/2023]
Abstract
Initially discovered in 1938 as a "fertility factor," vitamin E now refers to eight different isoforms that belong to two categories, four saturated analogues (α, β, γ, and δ) called tocopherols and four unsaturated analogues referred to as tocotrienols. While the tocopherols have been investigated extensively, little is known about the tocotrienols. Very limited studies suggest that both the molecular and therapeutic targets of the tocotrienols are distinct from those of the tocopherols. For instance, suppression of inflammatory transcription factor NF-κB, which is closely linked to tumorigenesis and inhibition of HMG-CoA reductase, mammalian DNA polymerases and certain protein tyrosine kinases, is unique to the tocotrienols. This review examines in detail the molecular targets of the tocotrienols and their roles in cancer, bone resorption, diabetes, and cardiovascular and neurological diseases at both preclinical and clinical levels. As disappointment with the therapeutic value of the tocopherols grows, the potential of these novel vitamin E analogues awaits further investigation.
Collapse
Affiliation(s)
- Bharat B Aggarwal
- Cytokine Research Laboratory, Department of Experimental Therapeutics, The University of Texas, M.D. Anderson Cancer Center, 1515 Holcombe Boulevard, Box 143, Houston, TX 77030, USA.
| | | | | | | |
Collapse
|
52
|
Kannappan R, Ravindran J, Prasad S, Sung B, Yadav VR, Reuter S, Chaturvedi MM, Aggarwal BB. γ-Tocotrienol Promotes TRAIL-Induced Apoptosis through Reactive Oxygen Species/Extracellular Signal-Regulated Kinase/p53–Mediated Upregulation of Death Receptors. Mol Cancer Ther 2010; 9:2196-207. [DOI: 10.1158/1535-7163.mct-10-0277] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
53
|
Liu M, Liu RH, Song BB, Li CF, Lin LQ, Zhang CP, Zhao JL, Liu JR. Antiangiogenetic Effects of 4 Varieties of Grapes In Vitro. J Food Sci 2010; 75:T99-104. [PMID: 20722961 DOI: 10.1111/j.1750-3841.2010.01662.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Ming Liu
- Treatment Center of Oncology, Fourth Hospital of Harbin Medical Univ., Harbin, P.R. China.
| | | | | | | | | | | | | | | |
Collapse
|
54
|
Bi S, Liu JR, Li Y, Wang Q, Liu HK, Yan YG, Chen BQ, Sun WG. gamma-Tocotrienol modulates the paracrine secretion of VEGF induced by cobalt(II) chloride via ERK signaling pathway in gastric adenocarcinoma SGC-7901 cell line. Toxicology 2010; 274:27-33. [PMID: 20452389 DOI: 10.1016/j.tox.2010.05.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2010] [Revised: 05/02/2010] [Accepted: 05/04/2010] [Indexed: 11/26/2022]
Abstract
Hypoxia is a common characteristic feature of solid tumors, and carcinoma cells are known to secrete many growth factors. These growth factors, such as vascular endothelial growth factor (VEGF), play a major role in the regulation of tumor angiogenesis and metastasis. In this study, the effect of gamma-tocotrienol, a natural product commonly found in palm oil and rice bran, on the accumulation of HIF-1alpha protein and the paracrine secretion of VEGF in human gastric adenocarcinoma SGC-7901 cell line induced by cobalt(II) chloride (as a hypoxia mimic) was investigated. These results showed that cobalt(II) chloride induced the high expression of VEGF in SGC-7901 cells at dose of 150 micromol/L for 24h. Both basal level and cobalt(II) chloride-induced HIF-1alpha protein accumulation and VEGF paracrine secretion were inhibited in SGC-7901 cells treated with gamma-tocotrienol at 60 micromol/L treatment for 24 h. U0126, a MEK1/2 inhibitor, decreased the expression of HIF-1alpha protein and the paracrine secretion of VEGF under normoxic and hypoxic conditions. In this study, gamma-tocotrienol also significantly inhibited the hypoxia-stimulated expression of phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2). The mechanism seems to involve in inhibiting hypoxia-mediated activation of p-ERK1/2, it leads to a marked decrease in hypoxia-induced HIF-1alpha protein accumulation and VEGF secretion. These data suggest that HIF-1alpha/VEGF could be a promising target for gamma-tocotrienol in an effective method of chemoprevention and chemotherapy in human gastric cancer.
Collapse
Affiliation(s)
- Sheng Bi
- Central Laboratory, The First Affiliated Hospital of Harbin Medical University, 23 YouZheng Street, NanGang District, Harbin 150001, People's Republic of China
| | | | | | | | | | | | | | | |
Collapse
|
55
|
Ju J, Picinich SC, Yang Z, Zhao Y, Suh N, Kong AN, Yang CS. Cancer-preventive activities of tocopherols and tocotrienols. Carcinogenesis 2010; 31:533-42. [PMID: 19748925 PMCID: PMC2860705 DOI: 10.1093/carcin/bgp205] [Citation(s) in RCA: 167] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2009] [Revised: 07/31/2009] [Accepted: 08/10/2009] [Indexed: 02/07/2023] Open
Abstract
The cancer-preventive activity of vitamin E has been studied. Whereas some epidemiological studies have suggested a protective effect of vitamin E against cancer formation, many large-scale intervention studies with alpha-tocopherol (usually large doses) have not demonstrated a cancer-preventive effect. Studies on alpha-tocopherol in animal models also have not demonstrated robust cancer prevention effects. One possible explanation for the lack of demonstrable cancer-preventive effects is that high doses of alpha-tocopherol decrease the blood and tissue levels of delta-tocopherols. It has been suggested that gamma-tocopherol, due to its strong anti-inflammatory and other activities, may be the more effective form of vitamin E in cancer prevention. Our recent results have demonstrated that a gamma-tocopherol-rich mixture of tocopherols inhibits colon, prostate, mammary and lung tumorigenesis in animal models, suggesting that this mixture may have a high potential for applications in the prevention of human cancer. In this review, we discuss biochemical properties of tocopherols, results of possible cancer-preventive effects in humans and animal models and possible mechanisms involved in the inhibition of carcinogenesis. Based on this information, we propose that a gamma-tocopherol-rich mixture of tocopherols is a very promising cancer-preventive agent and warrants extensive future research.
Collapse
Affiliation(s)
- Jihyeung Ju
- Department of Chemical Biology
- Department of Pharmaceutics
- Center for Cancer Prevention Research, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
- Cancer Institute of New Jersey, New Brunswick, NJ 08901, USA
- Present address: Department of Food and Nutrition, College of Human Ecology, Chungbuk National University, 410 Sungbong-Ro, Heungduk-Gu, Cheongju 361-763, Korea
| | - Sonia C. Picinich
- Department of Chemical Biology
- Department of Pharmaceutics
- Center for Cancer Prevention Research, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
- Cancer Institute of New Jersey, New Brunswick, NJ 08901, USA
| | - Zhihong Yang
- Department of Chemical Biology
- Department of Pharmaceutics
- Center for Cancer Prevention Research, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
- Cancer Institute of New Jersey, New Brunswick, NJ 08901, USA
| | - Yang Zhao
- Department of Chemical Biology
- Department of Pharmaceutics
- Center for Cancer Prevention Research, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
- Cancer Institute of New Jersey, New Brunswick, NJ 08901, USA
| | - Nanjoo Suh
- Department of Chemical Biology
- Department of Pharmaceutics
- Center for Cancer Prevention Research, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
- Cancer Institute of New Jersey, New Brunswick, NJ 08901, USA
| | - Ah-Ng Kong
- Department of Chemical Biology
- Department of Pharmaceutics
- Center for Cancer Prevention Research, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
- Cancer Institute of New Jersey, New Brunswick, NJ 08901, USA
| | - Chung S. Yang
- Department of Chemical Biology
- Department of Pharmaceutics
- Center for Cancer Prevention Research, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
- Cancer Institute of New Jersey, New Brunswick, NJ 08901, USA
| |
Collapse
|
56
|
Park SK, Sanders BG, Kline K. Tocotrienols induce apoptosis in breast cancer cell lines via an endoplasmic reticulum stress-dependent increase in extrinsic death receptor signaling. Breast Cancer Res Treat 2010; 124:361-75. [PMID: 20157774 DOI: 10.1007/s10549-010-0786-2] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2010] [Accepted: 02/04/2010] [Indexed: 01/20/2023]
Abstract
Tocotrienols are naturally occurring forms of vitamin E based on their structural similarity. This study focused on investigating anticancer effects of tocotrienols and the mechanisms of apoptosis induction by tocotrienols in vivo and in vitro. Dietary delivery of γ-tocotrienol (γ-T3) suppressed tumor growth in a syngeneic implantation mouse mammary cancer model by inhibiting cell proliferation and inducing apoptosis. In cell culture studies, γ-T3 inhibited colony formation of a mouse mammary cancer cell line and human breast cancer cell lines. The anti-proliferative effects of tocotrienols were highly correlated with an increase in apoptosis based on Annexin V assessment. Treatment of human MDA-MB-231 and MCF-7 cells with γ-T3 induced cleavages of PARP as well as caspase-8, -9, and -3. Additional analyses showed that γ-T3 activated c-Jun NH(2)-terminal kinase (JNK) and p38 MAPK, and upregulated death receptor 5 (DR5) and C/EBP homologous protein (CHOP), an endoplasmic reticulum (ER) stress marker. Silencing either JNK or p38 MAPK reduced the increase in DR5 and CHOP and partially blocked γ-T3-induced apoptosis. Both DR5 and CHOP upregulation were required for γ-T3-induced apoptosis, and DR5 was transcriptionally regulated by CHOP after γ-T3 treatment. Moreover, γ-T3 increased the level of other ER-stress markers. Taken together, these results suggest that upregulation of DR5 by γ-T3 treatment is dependent on JNK and p38 MAPK activation which is mediated by ER-stress.
Collapse
Affiliation(s)
- Sook Kyung Park
- Institute of Cellular and Molecular Biology/A5000, The University of Texas at Austin, Austin, TX 78712, USA
| | | | | |
Collapse
|
57
|
Wu SJ, Ng LT. Tocotrienols Inhibited Growth and Induced Apoptosis in Human HeLa Cells Through the Cell Cycle Signaling Pathway. Integr Cancer Ther 2010; 9:66-72. [DOI: 10.1177/1534735409357757] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Tocotrienols of palm oil have been shown to possess potent neuroprotective, antioxidative, anticancer, and cholesterol-lowering activities. In this study, the authors examined the antiproliferative effects of α-, γ- and δ-tocotrienols (αT3, γT3, and δT3), and α-tocopherol (αT) in human cervical carcinoma (HeLa) cells. Their mechanism(s) of action on cell cycle signaling pathway were also investigated. Results showed that the antiproliferative effect of αT3 (IC50: 3.19 ± 0.05 µM) and γT3 (IC 50: 2.85 ± 0.07 µM) was more potent than δT3 (IC 50: >100 µM) and αT (IC50: 69.46 ± 3.01 µM). Both αT3 and γT3 also demonstrated a dose-dependent and time-dependent induction of cell death.They caused cell cycle arrest at G2/M phase and triggered apoptosis as displayed by the externalization of annexin V—targeted phosphatidylserine and accumulation of sub-G1 peak. At a concentration of 3 µM, αT3 downregulated the expression of cyclin D3, p16, and CDK6, while having no effect on cyclin D1, p15, p21, p27, and CDK4 expression. However, γT3 showed no effect on these proteins. The induction of HeLa cell apoptosis by αT3 and γT3 appeared to be associated with the expression of IL-6, but not the other cytokines (IFN-γ, IL-2, and IL-10).Taken together, the results suggest that αT3 and γT3 are more effective than δT3 and αT in inhibiting HeLa cell proliferation, and their mode of action could be through the upregulation of IL-6, and the downregulation of cyclin D3, p16, and CDK6 expression in the cell cycle signaling pathway.
Collapse
Affiliation(s)
- Shu-Jing Wu
- Chia-Nan University of Pharmacy and Science, Tainan, Taiwan
| | | |
Collapse
|
58
|
Endoplasmic reticulum stress mediates γ-tocotrienol-induced apoptosis in mammary tumor cells. Apoptosis 2009; 14:1366-77. [DOI: 10.1007/s10495-009-0406-y] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|