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Nava-Tapia DA, Román-Justo NY, Cuenca-Rojo A, Guerrero-Rivera LG, Patrón-Guerrero A, Poblete-Cruz RI, Zacapala-Gómez AE, Sotelo-Leyva C, Navarro-Tito N, Mendoza-Catalán MA. Exploring the potential of tocopherols: mechanisms of action and perspectives in the prevention and treatment of breast cancer. Med Oncol 2024; 41:208. [PMID: 39060448 DOI: 10.1007/s12032-024-02454-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2024] [Accepted: 07/16/2024] [Indexed: 07/28/2024]
Abstract
Currently, breast cancer is the most common cause of mortality caused by neoplasia in women worldwide. The unmet challenges of conventional cancer therapy are chemoresistance and lack of selectivity, which can lead to serious side effects in patients; therefore, new treatments based on natural compounds that serve as adjuvants in breast cancer therapy are urgently needed. Tocopherols are naturally occurring antioxidant compounds that have shown antitumor activity against several types of cancer, including breast cancer. This review summarizes the antitumoral activity of tocopherols, such as the antiproliferative, apoptotic, anti-invasive, and antioxidant effects of tocopherols, through different molecular mechanisms. According to the studies described, α-T, δ-T and γ-T are the most studied in breast tumor cells; however, α-T and γ-T show a more critical antitumor activity and significant potential as a complements to chemotherapeutic drugs against breast cancer, enhancing toxicity against tumor cells and preventing cytotoxicity in nontumor cells. However, the possible relationship between tocopherol intake, related to concentration, and the promotion of cancer in particular cases should not be ruled out, so additional studies are required to determine the correct dose to obtain the desired antitumor effect. Moreover, nanomicelles of D-α-tocopherol have promising potential as pharmaceutical excipients for drug delivery to improve the cytotoxicity and selectivity of first-line chemotherapeutics against breast cancer.
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Affiliation(s)
- Dania A Nava-Tapia
- Facultad de Ciencias Químico Biológicas, Autonomous University of Guerrero, Av. Lázaro Cárdenas S/N., 39090, Chilpancingo, Guerrero, Mexico
| | - Norely Y Román-Justo
- Facultad de Ciencias Químico Biológicas, Autonomous University of Guerrero, Av. Lázaro Cárdenas S/N., 39090, Chilpancingo, Guerrero, Mexico
| | - Antonio Cuenca-Rojo
- Facultad de Ciencias Químico Biológicas, Autonomous University of Guerrero, Av. Lázaro Cárdenas S/N., 39090, Chilpancingo, Guerrero, Mexico
| | - Lizeth G Guerrero-Rivera
- Facultad de Ciencias Químico Biológicas, Autonomous University of Guerrero, Av. Lázaro Cárdenas S/N., 39090, Chilpancingo, Guerrero, Mexico
| | - Annet Patrón-Guerrero
- Facultad de Ciencias Químico Biológicas, Autonomous University of Guerrero, Av. Lázaro Cárdenas S/N., 39090, Chilpancingo, Guerrero, Mexico
| | - Ruth I Poblete-Cruz
- Facultad de Ciencias Químico Biológicas, Autonomous University of Guerrero, Av. Lázaro Cárdenas S/N., 39090, Chilpancingo, Guerrero, Mexico
| | - Ana E Zacapala-Gómez
- Facultad de Ciencias Químico Biológicas, Autonomous University of Guerrero, Av. Lázaro Cárdenas S/N., 39090, Chilpancingo, Guerrero, Mexico
| | - César Sotelo-Leyva
- Facultad de Ciencias Químico Biológicas, Autonomous University of Guerrero, Av. Lázaro Cárdenas S/N., 39090, Chilpancingo, Guerrero, Mexico
| | - Napoleón Navarro-Tito
- Facultad de Ciencias Químico Biológicas, Autonomous University of Guerrero, Av. Lázaro Cárdenas S/N., 39090, Chilpancingo, Guerrero, Mexico.
| | - Miguel A Mendoza-Catalán
- Facultad de Ciencias Químico Biológicas, Autonomous University of Guerrero, Av. Lázaro Cárdenas S/N., 39090, Chilpancingo, Guerrero, Mexico.
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Jia M, Pang S, Liu X, Mao Y, Wu C, Zhang H. Effect of dietary phytochemicals on the progression of breast cancer metastasis based on the in vivo detection of circulating tumor cells. J Funct Foods 2020. [DOI: 10.1016/j.jff.2019.103752] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Pan H, Wang F, Rankin GO, Rojanasakul Y, Tu Y, Chen YC. Inhibitory effect of black tea pigments, theaflavin‑3/3'-gallate against cisplatin-resistant ovarian cancer cells by inducing apoptosis and G1 cell cycle arrest. Int J Oncol 2017; 51:1508-1520. [PMID: 29048667 PMCID: PMC5642389 DOI: 10.3892/ijo.2017.4145] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 09/26/2017] [Indexed: 12/26/2022] Open
Abstract
Adverse side effects and acquired resistance to conventional chemotherapy based on platinum drive the exploration of other selective anticancer drugs. Theaflavin-3-gallate (TF2a) and theaflavin-3′-gallate (TF2b), theaflavin monomers in black tea, exhibited a potent growth inhibitory effect on cisplatin-resistant ovarian cancer A2780/CP70 cells and were less cytotoxic to normal ovarian IOSE-364 cell line. Flow cytometry analysis and western blotting indicated that TF2a and TF2b induced apoptosis and G1 cell cycle arrest in ovarian cancer A2780/CP70 cells. Hoechst 33342 staining was used to confirm the apoptotic effect. Downregulation of CDK2 and CDK4 for TF2a and CDK2 and cyclin E1 for TF2b led to the accumulation of cells in G1 phase. TF2a and TF2b induced apoptosis and G1 through p53-dependent pathways. TF2a and TF2b induced DNA damage through ATM/Chk/p53 pathway. TF2a and TF2b also induced inhibition of A2780/CP70 cells through Akt and MAPK pathways. The results of this study implied that TF2a and TF2b might help prevent and treat platinum-resistant ovarian cancer.
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Affiliation(s)
- Haibo Pan
- Department of Tea Science, Zhejiang University, Hangzhou, Zhejiang, P.R. China
| | - Fang Wang
- Department of Tea Science, Wuyi University, Wuyishan, Fujian, P.R. China
| | - Gary O Rankin
- Department of Biomedical Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV, USA
| | - Yon Rojanasakul
- Department of Pharmaceutical Sciences, West Virginia University, Morgantown, WV, USA
| | - Youying Tu
- Department of Tea Science, Zhejiang University, Hangzhou, Zhejiang, P.R. China
| | - Yi Charlie Chen
- College of Science, Technology and Mathematics, Alderson Broaddus University, Philippi, WV, USA
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Abstract
Four tocopherols are available in nature and are absorbed with the diet, but only one RRR-α-tocopherol satisfies the criteria of being a vitamin. The biological activity of the different tocopherols studied in the rat by the resorption-gestation test has been inconsistently extrapolated to human beings where the tocopherols have no influence on a successful pregnancy. Diminution of RRR-α-tocopherol intake results in diseases characterized by ataxia, whose pathogenetic mechanism, despite vigorous claims, has not been clarified. The calculation of the Daily Reference Intake (DRI), necessary to prevent disease, is based on an obsolete test, the peroxide-induced erythrocyte hemolysis, called the gold standard, but of highly questioned validity. If many epidemiological studies have given positive results, showing prevention by high vitamin E containing diets of cardiovascular events, neurodegenerative disease, macular degeneration and cancer, the clinical confirmatory intervention studies were mostly negative. On the positive side, besides preventing vitamin E deficiency diseases, vitamin E has shown efficacy as anti-inflammatory and immune boosting compound. It has also shown some efficacy in protecting against nonalcoholic hepato-steatosis. At a molecular level, vitamin E and some of its metabolites have shown capacity of regulating cell signaling and modulating gene transcription.
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Affiliation(s)
- Angelo Azzi
- Vascular Biology Laboratory, JM USDA-HNRCA at Tufts University, Boston, MA 02111, USA.
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Tu Y, Kim E, Gao Y, Rankin GO, Li B, Chen YC. Theaflavin-3, 3'-digallate induces apoptosis and G2 cell cycle arrest through the Akt/MDM2/p53 pathway in cisplatin-resistant ovarian cancer A2780/CP70 cells. Int J Oncol 2016; 48:2657-65. [PMID: 27082635 PMCID: PMC4863729 DOI: 10.3892/ijo.2016.3472] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Accepted: 02/11/2016] [Indexed: 01/07/2023] Open
Abstract
Ovarian cancer is the most lethal gynecological cancer among women worldwide. Adverse side effects and acquired resistance to conventional platinum based chemotherapy are major impediments in ovarian cancer treatment, and drive the development of more selective anticancer drugs that target cancer-specific defects. In this study, theaflavin-3, 3′-digallate (TF3), the major theaflavin monomer in black tea, exhibited a potent growth inhibitory effect on the cisplatin-resistant ovarian cancer A2780/CP70 cells (IC50, 23.81 μM), and was less cytotoxic to a normal ovarian IOSE-364 cells (IC50, 59.58 μM) than to the cancer cells. Flow cytometry analysis indicated that TF3 induced preferential apoptosis and G2 cell cycle arrest in A2780/CP70 cells with respect to IOSE-364 cells. TF3 induced apoptosis through both the intrinsic and extrinsic apoptotic pathways, and caused G2 cell cycle arrest via cyclin B1 in A2780/CP70 cells. The p53 protein played an important role in TF3-induced apoptosis and G2 cell cycle arrest. TF3 might upregulate the p53 expression via the Akt/MDM2 pathway. Our findings help elucidate the mechanisms by which TF3 may contribute to the prevention and treatment of platinum-resistant ovarian cancer.
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Affiliation(s)
- Youying Tu
- Department of Tea Science, Zhejiang University, Hangzhou, Zhejiang 310058, P.R. China
| | - Eunhye Kim
- Department of Tea Science, Zhejiang University, Hangzhou, Zhejiang 310058, P.R. China
| | - Ying Gao
- Department of Tea Science, Zhejiang University, Hangzhou, Zhejiang 310058, P.R. China
| | - Gary O Rankin
- Department of Pharmacology, Physiology and Toxicology, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV 25755, USA
| | - Bo Li
- Department of Tea Science, Zhejiang University, Hangzhou, Zhejiang 310058, P.R. China
| | - Yi Charlie Chen
- Department of Tea Science, Zhejiang University, Hangzhou, Zhejiang 310058, P.R. China
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Wang C, Li C, Leslie CA, Sun Q, Guo X, Yang K. Molecular cloning and heterologous expression analysis of JrVTE1 gene from walnut ( Juglans regia). MOLECULAR BREEDING : NEW STRATEGIES IN PLANT IMPROVEMENT 2015; 35:222. [PMID: 26612974 PMCID: PMC4648991 DOI: 10.1007/s11032-015-0414-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 11/09/2015] [Indexed: 06/05/2023]
Abstract
Tocopherol cyclase (VTE1) plays a key role in promoting the production of γ-tocopherol and improving total tocopherol content in photosynthetic organisms. Walnut is an important source of tocopherols in the human diet, and γ-tocopherol is the major tocopherol compound in walnut kernels. In this study, a full-length cDNA of the VTE1 gene was isolated from walnut using RT-PCR and RACE, and designated as JrVTE1. The full-length cDNA of the JrVTE1 gene contained a 1353-bp open-reading frame encoding a 451-amino-acid protein with a calculated molecular weight of 49.5 kDa. The deduced JrVTE1 protein had a considerable homology with other plant VTE1s and belonged to the tocopherol cyclase family. Functional characterization of JrVTE1 by heterologous expression was carried out in E. coli BL21 (DE3) and microshoot lines of the fruit trees jujube (Zizyphus jujuba var. spinosa) and pear (Pyrus communis) cultivar 'Old Home'. JrVTE1 in E. coli expressed as a 50 kDa protein, as expected. One or two copies of the transferred JrVTE1 gene were detected in the genomes of representative transgenic lines (from the initial transgenic plants) of jujube and pear by gel blots analysis. Over-expression of JrVTE1 in jujube and pear resulted in an accumulation of tocopherol and a shift in tocopherol composition in leaf, root and stem tissues. In the transgenic jujube, the total tocopherol content increased by 29.8 μg/g in the stems of line J3, 43.7 and 22.5 μg/g in the roots and leaves of line J1, respectively, whereas in the transgenic pear it increased by 47.3 μg/g in the leaf of line P3, and 16.7 and 10.4 μg/g in roots and stems of line P9, respectively. In the examined tissues of transgenic plants, the highest accumulation rate was the γ-tocopherol. These results indicate that JrVTE1 is one of the rate-limiting enzymes for tocopherol production and could be used to improve the tocopherol content of tree crops through genetic engineering.
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Affiliation(s)
- Cancan Wang
- />College of Forestry, Shandong Agricultural University, Taian, 271018 Shandong Province People’s Republic of China
- />Shandong Taishan Forest Ecosystem Research Station, Taian, 271018 People’s Republic of China
| | - Chuanrong Li
- />College of Forestry, Shandong Agricultural University, Taian, 271018 Shandong Province People’s Republic of China
- />Shandong Taishan Forest Ecosystem Research Station, Taian, 271018 People’s Republic of China
| | - Charles A. Leslie
- />Department of Plant Sciences, University of California-Davis, Davis, CA 95616 USA
| | - Qingrong Sun
- />Shandong Institute of Pomology, Taian, 271018 Shandong Province People’s Republic of China
| | - Xianfeng Guo
- />College of Forestry, Shandong Agricultural University, Taian, 271018 Shandong Province People’s Republic of China
| | - Keqiang Yang
- />College of Forestry, Shandong Agricultural University, Taian, 271018 Shandong Province People’s Republic of China
- />Shandong Taishan Forest Ecosystem Research Station, Taian, 271018 People’s Republic of China
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Li B, Gao Y, Rankin GO, Rojanasakul Y, Cutler SJ, Tu Y, Chen YC. Chaetoglobosin K induces apoptosis and G2 cell cycle arrest through p53-dependent pathway in cisplatin-resistant ovarian cancer cells. Cancer Lett 2014; 356:418-33. [PMID: 25304379 DOI: 10.1016/j.canlet.2014.09.023] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Revised: 07/26/2014] [Accepted: 09/15/2014] [Indexed: 11/16/2022]
Abstract
Adverse side effects and acquired resistance to conventional platinum based chemotherapy have become major impediments in ovarian cancer treatment, and drive the development of more selective anticancer drugs. Chaetoglobosin K (ChK) was shown to have a more potent growth inhibitory effect than cisplatin on two cisplatin-resistant ovarian cancer cell lines, OVCAR-3 and A2780/CP70, and was less cytotoxic to a normal ovarian cell line, IOSE-364, than to the cancer cell lines. Hoechst 33342 staining and Flow cytometry analysis indicated that ChK induced preferential apoptosis and G2 cell cycle arrest in both ovarian cancer cells with respect to the normal ovarian cells. ChK induced apoptosis through a p53-dependent caspase-8 activation extrinsic pathway, and caused G2 cell cycle arrest via cyclin B1 by increasing p53 expression and p38 phosphorylation in OVCAR-3 and A2780/CP70 cells. DR5 and p21 might play an important role in determining the sensitivity of normal and malignant ovarian cells to ChK. Based on these results, ChK would be a potential compound for treating platinum-resistant ovarian cancer.
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Affiliation(s)
- Bo Li
- College of Science, Technology and Mathematics, Alderson Broaddus University, Philippi, WV 26416, USA; Department of Tea Science, Zhejiang University, Hangzhou 310058, China
| | - Ying Gao
- College of Science, Technology and Mathematics, Alderson Broaddus University, Philippi, WV 26416, USA; Department of Tea Science, Zhejiang University, Hangzhou 310058, China
| | - Gary O Rankin
- Department of Pharmacology, Physiology and Toxicology, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV 25755, USA
| | - Yon Rojanasakul
- Department of Pharmaceutical Science, West Virginia University, Morgantown, WV 26506, USA
| | - Stephen J Cutler
- Department of Medicinal Chemistry, University of Mississippi, University, MS 38677, USA
| | - Youying Tu
- Department of Tea Science, Zhejiang University, Hangzhou 310058, China.
| | - Yi Charlie Chen
- College of Science, Technology and Mathematics, Alderson Broaddus University, Philippi, WV 26416, USA.
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Engin KN, Erdem-Kuruca S, Akgün-Dar K, Çetin B, Karadenizli S, Gürel E, Yemisci B, Bilgiç S, Arslan M. The Evaluation of Human Tenon’s Fibroblasts and Endothelial Cell Responses to Antifibrotics Alone and in Combination with α-Tocopherol. Curr Eye Res 2014; 40:19-29. [DOI: 10.3109/02713683.2014.909496] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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9
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Synthesis and screening of novel vitamin E derivatives for anticancer functions. Eur J Med Chem 2012; 58:72-83. [DOI: 10.1016/j.ejmech.2012.09.045] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Revised: 09/24/2012] [Accepted: 09/27/2012] [Indexed: 12/24/2022]
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Gopalan A, Yu W, Jiang Q, Jang Y, Sanders BG, Kline K. Involvement of de novo ceramide synthesis in gamma-tocopherol and gamma-tocotrienol-induced apoptosis in human breast cancer cells. Mol Nutr Food Res 2012; 56:1803-11. [PMID: 23065795 DOI: 10.1002/mnfr.201200350] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2012] [Revised: 08/11/2012] [Accepted: 08/24/2012] [Indexed: 11/11/2022]
Abstract
SCOPE This study further examines mechanisms involved in the pro-apoptotic action of gamma-tocopherol (γT) and gamma-tocotrienol (γT3) in human breast cancer cell lines. METHODS AND RESULTS γT upregulates phospho-JNK (pJNK), CCAAT/enhancer-binding protein homologous protein (CHOP), and death receptor-5 (DR5) protein expression as detected by Western blot assays. siRNA knockdown of JNK, CHOP, or DR5 shows that γT-induced apoptosis is JNK/CHOP/DR5 signaling dependent, which is similar to γT3-mediated apoptotic signaling. Furthermore, both γT and γT3 induce increased levels of cellular ceramides and dihydroceramides as determined by LC-MS/MS analyses. Inhibition of de novo ceramide synthesis using chemical inhibitors blocked the ability of γT and γT3 to induce apoptosis as detected by Annexin V-FITC/PI assay and to activate JNK/CHOP/DR5 pro-apoptotic signaling thereby demonstrating the involvement of de novo ceramide synthesis in γT- and γT3-induced apoptosis. CONCLUSION Taken together, data show that both γT and γT3 induce apoptosis via de novo ceramide synthesis dependent activation of JNK/CHOP/DR5 pro-apoptotic signaling.
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Affiliation(s)
- Archana Gopalan
- Department of Nutritional Sciences, University of Texas at Austin, Austin, TX 78712, USA
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Gamma Tocopherol and Lovastatin Additively Induced Apoptosis in Human Colorectal Carcinoma Cell Line (HT29). Jundishapur J Nat Pharm Prod 2012. [DOI: 10.5812/jjnpp.4860] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Zeidooni L, Rezaei M, Hashemi Tabar M. Gamma Tocopherol and Lovastatin Additively Induced Apoptosis in Human Colorectal Carcinoma Cell Line (HT29). Jundishapur J Nat Pharm Prod 2012. [DOI: 10.17795/jjnpp-4860] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Farooqi AA, Bhatti S, Ismail M. TRAIL and vitamins: opting for keys to castle of cancer proteome instead of open sesame. Cancer Cell Int 2012; 12:22. [PMID: 22672528 PMCID: PMC3502079 DOI: 10.1186/1475-2867-12-22] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Accepted: 04/26/2012] [Indexed: 12/18/2022] Open
Abstract
Cancer is a multifaceted molecular disorder that is modulated by a combination of genetic, metabolic and signal transduction aberrations, which severely impair the normal homeostasis of cell growth and death. Accumulating findings highlight the fact that different genetic alterations, such as mutations in tumor suppressor genes, might be related to distinct and differential sensitivity to targeted therapies. It is becoming increasingly apparent that a multipronged approach that addresses genetic milieu (alterations in upstream and/or parallel pathways) eventually determines the response of individual tumors to therapy. Cancerous cells often acquire the ability to evade death by attenuating cell death pathways that normally function to eliminate damaged and harmful cells. Therefore impaired cell death nanomachinery and withdrawal of death receptors from cell surface are some of major determinants for the development of chemotherapeutic resistance encountered during treatment. It is therefore essential to emphasize underlying factors which predispose cells to refractoriness against TRAIL mediated cell death pathway and the relevant regulatory components involved. We bring to limelight the strategies to re-sensitize TRAIL resistant cells via vitamins to induce apoptosis.
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Affiliation(s)
- Ammad Ahmad Farooqi
- Lab for Translational Oncology and Personalized Medicine, Rashid Latif Medical College (RLMC), 35 km Ferozepur Road, Lahore, Pakistan.
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Wong RSY, Radhakrishnan AK, Ibrahim TAT, Cheong SK. δ- and γ-tocotrienols induce classical ultrastructural apoptotic changes in human T lymphoblastic leukemic cells. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2012; 18:462-469. [PMID: 22640960 DOI: 10.1017/s1431927612000177] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Tocotrienols are isomers of the vitamin E family, which have been reported to exert cytotoxic effects in various cancer cells. Although there have been some reports on the effects of tocotrienols in leukemic cells, ultrastructural evidence of tocotrienol-induced apoptotic cell death in leukemic cells is lacking. The present study investigated the effects of three isomers of tocotrienols (alpha, delta, and gamma) on a human T lymphoblastic leukemic cell line (CEM-SS). Cell viability assays showed that all three isomers had cytotoxic effects (p < 0.05) on CEM-SS cells with delta-tocotrienol being the most potent. Transmission electron microscopy showed that the cytotoxic effects by delta- and gamma-tocotrienols were through the induction of an apoptotic pathway as demonstrated by the classical ultrastructural apoptotic changes characterized by peripheral nuclear chromatin condensation and nuclear fragmentation. These findings were confirmed biochemically by the demonstration of phosphatidylserine externalization via flow cytometry analysis. This is the first study showing classical ultrastructural apoptotic changes induced by delta- and gamma-tocotrienols in human T lymphoblastic leukemic cells.
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Affiliation(s)
- Rebecca S Y Wong
- Division of Human Biology, School of Medical and Health Sciences, International Medical University, Malaysia No 126, Jalan Jalil Perkasa 19, Bukit Jalil, 57000 Kuala Lumpur, Malaysia. mail:
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15
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Zeidooni L, Rezaei M, Hashemi Tabar M. Gamma Tocopherol and Lovastatin Additively Induced Apoptosis in Human Colorectal Carcinoma Cell Line (HT29). Jundishapur J Nat Pharm Prod 2012; 7:153-8. [PMID: 24624174 PMCID: PMC3941870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Revised: 06/13/2012] [Accepted: 07/23/2012] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Programmed cell death (apoptosis) is a physiological process needed to remove unwanted or damaged cells. It has been hypothesized that any failure of programmed cell death leads to the development of neoplasm. Identifying new agents which induce apoptosis in tumor cells is of great significance in treatment of neoplasms. Numerous studies suggest that exposure of tumor cells to statins and gamma tocopherol can lead to cell death. OBJECTIVES The aim of this study was to evaluate the cell death induced by gamma tocopherol and lovastatin in human colorectal carcinoma cell line (HT29) using flow cytometry. MATERIAL AND METHODS HT29 cells were grown in DMEM medium, exposed to different concentrations of lovastatin (10,20,40,100μM ) and gamma tocopherol (25,50,100,200μM) for 48 and 72 hours, individually and in combination (100μM both, 48 h). Phenotype of apoptosis was determined by means of flow cytometry. RESULTS All Concentrations of lovastatin (10, 20, 40, 100 μM) and gamma tocopherol (25, 50, 100, 200 μM) induced an apoptotic response in HT29 cells. In combination, a significant increase in apoptosis phenotype was also demonstrated (P < 0.05). CONCLUSIONS This study showed that lovastatin when combined with gamma tocopherol, could induce apoptosis in HT29 cells more potently than each agent alone, which uncovers the significance of targeting the proliferative signaling in different points of the pathway.
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Affiliation(s)
- Leila Zeidooni
- Department of Toxicology, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, IR Iran
| | - Mohsen Rezaei
- Department of Toxicology, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, IR Iran,Corresponding author: Mohsen Rezaei, Department of Toxicology, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, IR Iran, Tel: +98-6113738380,
| | - Mahmood Hashemi Tabar
- Department of Cellular and Molecular Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, IR Iran
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Zheng X, Cui XX, Khor TO, Huang Y, DiPaola RS, Goodin S, Lee MJ, Yang CS, Kong AN, Allan H. C. Inhibitory Effect of a γ-Tocopherol-Rich Mixture of Tocopherols on the Formation and Growth of LNCaP Prostate Tumors in Immunodeficient Mice. Cancers (Basel) 2011; 3:3762-72. [PMID: 24213110 PMCID: PMC3763395 DOI: 10.3390/cancers3043762] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2011] [Revised: 09/15/2011] [Accepted: 09/15/2011] [Indexed: 01/11/2023] Open
Abstract
In the present study, we determined the effects of a γ-tocopherol-rich mixture of tocopherols (γ-TmT) on the growth and apoptosis of cultured human prostate cancer LNCaP cells. We also determined the effects of dietary γ-TmT on the formation and growth of LNCaP tumors in immunodeficient mice. In the in vitro study, we found that the activity of γ-TmT was stronger than α-tocopherol for inhibiting the growth and stimulating apoptosis in LNCaP cells. In the animal study, treatment of severe combined immunodeficient (SCID) mice with dietary γ-TmT inhibited the formation and growth of LNCaP xenograft tumors in a dose-dependent manner. Mechanistic studies showed that γ-TmT administration inhibited proliferation as reflected by decreased mitosis and stimulated apoptosis as reflected by increased caspase-3 (active form) expression in LNCaP tumors. In addition, dietary administration of γ-TmT increased the levels of α-, γ- and δ- tocopherol in plasma, and increased levels of γ- and δ- tocopherol were also observed in the prostate and in tumors. The present study demonstrated that γ-TmT had strong anticancer activity both in vitro and in vivo. Additional studies are needed to determine the potential preventive effect of γ-TmT for prostate cancer in humans.
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Affiliation(s)
- Xi Zheng
- Susan Lehman Cullman Laboratory for Cancer Research, Department of Chemical Biology, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, 164 Frelinghuysen Road, Piscataway, NJ 08854, USA; E-Mails: (X.-X.C.); (M.J.L.); (C.S.Y.); (A.H.C.)
- Cancer Institute of New Jersey, New Brunswick, NJ 08903, USA; E-Mails: (R.S.D.); (S.G.); (A.-N. K.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +1-732-445-4940; Fax: +1-732-445-0687
| | - Xiao-Xing Cui
- Susan Lehman Cullman Laboratory for Cancer Research, Department of Chemical Biology, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, 164 Frelinghuysen Road, Piscataway, NJ 08854, USA; E-Mails: (X.-X.C.); (M.J.L.); (C.S.Y.); (A.H.C.)
| | - Tin Oo Khor
- Department of Pharmaceutics, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA; E-Mails: (T.O.K.); (Y.H.)
| | - Ying Huang
- Department of Pharmaceutics, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA; E-Mails: (T.O.K.); (Y.H.)
| | - Robert S DiPaola
- Cancer Institute of New Jersey, New Brunswick, NJ 08903, USA; E-Mails: (R.S.D.); (S.G.); (A.-N. K.)
| | - Susan Goodin
- Cancer Institute of New Jersey, New Brunswick, NJ 08903, USA; E-Mails: (R.S.D.); (S.G.); (A.-N. K.)
| | - Mao-Jung Lee
- Susan Lehman Cullman Laboratory for Cancer Research, Department of Chemical Biology, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, 164 Frelinghuysen Road, Piscataway, NJ 08854, USA; E-Mails: (X.-X.C.); (M.J.L.); (C.S.Y.); (A.H.C.)
| | - Chung S Yang
- Susan Lehman Cullman Laboratory for Cancer Research, Department of Chemical Biology, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, 164 Frelinghuysen Road, Piscataway, NJ 08854, USA; E-Mails: (X.-X.C.); (M.J.L.); (C.S.Y.); (A.H.C.)
- Cancer Institute of New Jersey, New Brunswick, NJ 08903, USA; E-Mails: (R.S.D.); (S.G.); (A.-N. K.)
| | - Ah-Ng Kong
- Cancer Institute of New Jersey, New Brunswick, NJ 08903, USA; E-Mails: (R.S.D.); (S.G.); (A.-N. K.)
- Department of Pharmaceutics, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA; E-Mails: (T.O.K.); (Y.H.)
| | - Conney Allan H.
- Susan Lehman Cullman Laboratory for Cancer Research, Department of Chemical Biology, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, 164 Frelinghuysen Road, Piscataway, NJ 08854, USA; E-Mails: (X.-X.C.); (M.J.L.); (C.S.Y.); (A.H.C.)
- Cancer Institute of New Jersey, New Brunswick, NJ 08903, USA; E-Mails: (R.S.D.); (S.G.); (A.-N. K.)
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Li GX, Lee MJ, Liu AB, Yang Z, Lin Y, Shih WJ, Yang CS. δ-tocopherol is more active than α - or γ -tocopherol in inhibiting lung tumorigenesis in vivo. Cancer Prev Res (Phila) 2011; 4:404-13. [PMID: 21372040 DOI: 10.1158/1940-6207.capr-10-0130] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
In contrast to strong epidemiologic, preclinical, and secondary clinical evidence for vitamin E (tocopherols) in reducing cancer risk, large-scale clinical cancer-prevention trials of α-tocopherol have been negative. This vexing contrast helped spur substantial preclinical efforts to better understand and improve the antineoplastic activity of tocopherol through, for example, the study of different tocopherol forms. We previously showed that the γ-tocopherol-rich mixture (γ-TmT) effectively inhibited colon and lung carcinogenesis and the growth of transplanted lung-cancer cells in mice. We designed this study to determine the relative activities of different forms of tocopherol in a xenograft model, comparing the anticancer activities of δ-tocopherol with those of α- and γ-tocopherols. We subcutaneously injected human lung cancer H1299 cells into NCr nu/nu mice, which then received α-, γ-, or δ-tocopherol or γ-TmT in the diet (each at 0.17% and 0.3%) for 49 days. δ-Tocopherol inhibited tumor growth most strongly. γ-Tocopherol and γ-TmT (at 0.3%) also inhibited growth significantly, but α-tocopherol did not. δ-Tocopherol also effectively decreased oxidative DNA damage and nitrotyrosine formation and enhanced apoptosis in tumor cells; again, γ-tocopherol also was active in these regards but less so, and α-tocopherol was not. Each supplemented diet increased serum levels of its tocopherol - up to 45 μmol/L for α-tocopherol, 9.7 μmol/L for γ-tocopherol, and 1.2 μmol/L for δ-tocopherol; dietary γ- or δ-tocopherol, however, decreased serum α-tocopherol levels, and dietary α-tocopherol decreased serum levels of γ-tocopherol. Each dietary tocopherol also increased its corresponding side-chain-degradation metabolites, with concentrations of δ-tocopherol metabolites greater than γ-tocopherol and far greater than α-tocopherol metabolites in serum and tumors. This study is the first in vivo assessment of δ-tocopherol in tumorigenesis and shows that δ-tocopherol is more active than α- or γ-tocopherol in inhibiting tumor growth, possibly through trapping reactive oxygen and nitrogen species and inducing apoptosis; δ-tocopherol metabolites could contribute significantly to these results.
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Affiliation(s)
- Guang-Xun Li
- Department of Chemical Biology and Center for Cancer Prevention Research, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
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Zhang X, Peng X, Yu W, Hou S, Zhao Y, Zhang Z, Huang X, Wu K. Alpha-tocopheryl succinate enhances doxorubicin-induced apoptosis in human gastric cancer cells via promotion of doxorubicin influx and suppression of doxorubicin efflux. Cancer Lett 2011; 307:174-81. [PMID: 21536373 DOI: 10.1016/j.canlet.2011.04.001] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2010] [Revised: 03/30/2011] [Accepted: 04/06/2011] [Indexed: 12/11/2022]
Abstract
Doxorubicin (DOXO), a chemotherapy drug, is widely used in clinic for treating a variety of cancers. However, the treatment eventfully fails due to drug resistance and toxicity. Therefore, a combination strategy is needed to increase efficacy and reduce toxicity of DOXO. alpha-tocopheryl succinate (α-TOS) exhibits anticancer actions in vitro and in vivo. Here, we reported that combination of DOXO+α-TOS cooperatively acted to induce apoptosis in SGC-7901 cells. α-TOS enhanced cellular level of DOXO via promotion of DOXO influx and suppression of DOXO efflux. DOXO induced MDR1 mRNA and protein expression and α-TOS inhibited this event, indicating that α-TOS suppressed DOXO efflux via inhibition of MDR1. Furthermore, combination of DOXO+α-TOS induced increased levels of Fas and Bax protein expression and cleavage of caspase-8 and caspase-9, suggesting that combination treatment induced Fas/caspase-8 and Bax mediated mitochondria dependent apoptosis. Taken together, our results demonstrated that α-TOS enhanced DOXO anticancer efficiency via promotion of DOXO influx and suppression of MDR-1 mediated DOXO efflux.
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Affiliation(s)
- Xuguang Zhang
- Department of Nutrition and Food, Harbin Medical University, Harbin, China
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19
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Yu W, Tiwary R, Li J, Park SK, Jia L, Xiong A, Simmons-Menchaca M, Sanders BG, Kline K. α-TEA induces apoptosis of human breast cancer cells via activation of TRAIL/DR5 death receptor pathway. Mol Carcinog 2010; 49:964-73. [PMID: 20886583 DOI: 10.1002/mc.20681] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Vitamin E derivative RRR-α-tocopherol ether-linked acetic acid analog (α-TEA) induces apoptosis in MCF-7 and HCC-1954 human breast cancer cells in a dose- and time-dependent manner. α-TEA induces increased levels of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and death receptor-5 (DR5) and decreased levels of antiapoptotic factor, cellular FLICE-like inhibitory protein (c-FLIP L). DR5/TRAIL induced apoptosis involves downregulation of c-FLIP (L), caspase-8 activation, activated proapoptotic mediators tBid and Bax, mitochondrial permeability transition, and activation of caspase-9. siRNA knockdown of either DR5 or TRAIL blocks the ability of α-TEA to enhance DR5 protein levels, downregulate c-FLIP(L) protein levels and induce apoptosis. Combination of α-TEA + TRAIL acts cooperatively to induce apoptosis, and increase DR5 and decrease c-FLIP (L) protein levels. siRNA knockdown of c-FLIP produces a low level of spontaneous apoptosis and enhances α-TEA- and TRAIL-induced apoptosis. Taken together, these studies show that α-TEA induces TRAIL/DR5 mitochondria-dependent apoptosis in human breast cancer cells, and that TRAIL/DR5-dependent increases in DR5 and decreases in c-FLIP expression are triggered by TRAIL or α-TEA treatments.
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20
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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]
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21
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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.
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Affiliation(s)
- Sook Kyung Park
- Institute of Cellular and Molecular Biology/A5000, The University of Texas at Austin, Austin, TX 78712, USA
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22
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Yu W, Jia L, Park SK, Li J, Gopalan A, Simmons-Menchaca M, Sanders BG, Kline K. Anticancer actions of natural and synthetic vitamin E forms: RRR-alpha-tocopherol blocks the anticancer actions of gamma-tocopherol. Mol Nutr Food Res 2009; 53:1573-81. [PMID: 19842103 PMCID: PMC3008344 DOI: 10.1002/mnfr.200900011] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Two naturally occurring dietary sources of vitamin E (i.e. RRR-alpha-tocopherol (alphaT) and RRR-gamma-tocopherol (gammaT)), the manufactured synthetic form of vitamin E, all-racemic-alpha-tocopherol (all-rac-alphaT), as well as a potent antitumor analog of vitamin E, RRR-alpha-tocopherol ether-linked acetic acid analog (alpha-TEA), were assessed for anticancer actions. Data showed that gammaT, all-rac-alphaT, and alpha-TEA but not alphaT or alphaT+gammaT significantly inhibited tumor burden of human MDA-MB-231 cells in nude mice. Immunohistochemical analyses of tumor tissue showed that all-rac-alphaT and alpha-TEA increased apoptosis and decreased proliferation in tumor cells while gammaT was associated with increased tumor cell apoptosis only. In vitro data showed alpha-TEA and gammaT but not all-rac-alphaT or alphaT to inhibit colony formation and induce apoptosis. Anticancer actions of alpha-TEA and gammaT involved death receptor 5 protein upregulation, Survivin protein downregulation and poly (ADP-ribose) polymerase cleavage, all of which were blocked by co-treatment with alphaT. In summary, both gammaT and alpha-TEA exhibited promising anticancer properties in vivo and in vitro, whereas all-rac-alphaT exhibited promising anticancer properties in vivo only. Importantly, alphaT not only failed to exhibit anticancer properties but it also reduced anticancer actions of gammaT in vivo and gammaT and alpha-TEA in vitro.
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Affiliation(s)
- Weiping Yu
- Department of Nutritional Sciences/A2703, University of Texas at Austin, Austin, TX, USA
- School of Biological Sciences, University of Texas at Austin, Austin, TX, USA
| | - Li Jia
- School of Biological Sciences, University of Texas at Austin, Austin, TX, USA
| | - Sook-Kyung Park
- School of Biological Sciences, University of Texas at Austin, Austin, TX, USA
| | - Jing Li
- School of Biological Sciences, University of Texas at Austin, Austin, TX, USA
| | - Archana Gopalan
- Department of Nutritional Sciences/A2703, University of Texas at Austin, Austin, TX, USA
| | | | - Bob G. Sanders
- School of Biological Sciences, University of Texas at Austin, Austin, TX, USA
| | - Kimberly Kline
- Department of Nutritional Sciences/A2703, University of Texas at Austin, Austin, TX, USA
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Sanguinarine induces apoptosis in A549 human lung cancer cells primarily via cellular glutathione depletion. Toxicol In Vitro 2008; 23:281-7. [PMID: 19135517 DOI: 10.1016/j.tiv.2008.12.013] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2008] [Revised: 10/23/2008] [Accepted: 12/09/2008] [Indexed: 12/14/2022]
Abstract
Sanguinarine is a plant-derived benzophenanthridine alkaloid and has been shown to possess anti-tumor activities against various cancer cells. In this study, we investigated whether sanguinarine induces apoptosis in A549 human lung cancer cells. Treatment of A549 cells with sanguinarine induced apoptosis in a dose- and time-dependent manner. Treatment with sanguinarine led to activation of caspases and MAPKs as well as increased MKP-1 expression. Importantly, pretreatment with z-VAD-fmk, a pan caspase inhibitor suppressed the sanguinarine-induced apoptosis in A549 cells. Moreover, pretreatment with NAC, a sulfhydryl group-containing reducing agent strongly suppressed the apoptotic response and caspase activation to sanguinarine. However, the sanguinarine-mediated cytotoxicity in A549 cells was not protected by pharmacological inhibition of MAPKs or MKP-1 siRNA-mediated knockdown of MKP-1. These results collectively suggest that sanguinarine induces apoptosis in A549 cells through cellular glutathione depletion and the subsequent caspase activation.
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Novel anthraquinone derivatives: Synthesis via click chemistry approach and their induction of apoptosis in BGC gastric cancer cells via reactive oxygen species(ROS)-dependent mitochondrial pathway. Bioorg Med Chem Lett 2008; 18:6505-8. [DOI: 10.1016/j.bmcl.2008.10.047] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2008] [Revised: 09/25/2008] [Accepted: 10/10/2008] [Indexed: 11/17/2022]
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