Tocotrienol-rich mixture inhibits cell proliferation and induces apoptosis via down-regulation of the Notch-1/NF-κB pathways in NSCLC cells
Lichchavi D Rajasinghe, Smiti V Gupta Department of Nutrition and Food Science, Wayne State University, Detroit, MI, USA Abstract: Lung cancer is one of the leading causes of cancer deaths. Non-small cell lung cancer (NSCLC), with a 5-year survival rate of 5% at stage IIIB, accounts for 80%...
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| Format: | Article |
| Language: | English |
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Dove Medical Press
2017-12-01
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| Series: | Nutrition and Dietary Supplements |
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| Online Access: | https://www.dovepress.com/tocotrienol-rich-mixture-inhibits-cell-proliferation-and-induces-apopt-peer-reviewed-article-NDS |
| _version_ | 1811264785009868800 |
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| author | Rajasinghe LD Gupta SV |
| author_facet | Rajasinghe LD Gupta SV |
| author_sort | Rajasinghe LD |
| collection | DOAJ |
| description | Lichchavi D Rajasinghe, Smiti V Gupta Department of Nutrition and Food Science, Wayne State University, Detroit, MI, USA Abstract: Lung cancer is one of the leading causes of cancer deaths. Non-small cell lung cancer (NSCLC), with a 5-year survival rate of 5% at stage IIIB, accounts for 80%–85% of all lung cancers. Aberrant Notch-1 expressions have been reported in lung cancer patients and could potentially be a beneficial molecular/therapeutic target against NSCLC. Tocotrienols, isomers of vitamin E, have been shown to exhibit antitumor activity via inhibition of different signaling pathways in tumor cells. Previously, we reported that delta-tocotrienol downregulates Notch-1 via NF-κB. However, the pure isomers are presently not available in quantities required for animal or clinical studies. Therefore, the objective of this study was to investigate the interactions and effects of commercially available tocotrienols (a mixture of isomers) on the Notch-1 pathway in NSCLC, adenocarcinoma (A549) and squamous cell lung cancer (H520) cell lines. A dose-dependent decrease in all growth, cell migration, and tumor invasiveness was observed in both cancer cell lines with the addition of tocotrienols. A significant induction of apoptosis was also observed using Annexin V stain in flow cytometry analysis. Since tocotrienols significantly affected proliferation, apoptosis, migration, and invasiveness, reverse transcription polymerase chain reaction and Western blot analysis were used to explore the molecular mechanisms responsible for the regulations by testing the expression of Notch-1 and its downstream genes. A dose-dependent decrease in expression of proteins was observed in Notch-1, Hes-1, Survivin, and Bcl-XL. In addition, we found a mechanism linking the NF-κB pathway and Notch-1 down-regulation from NF-κB DNA-binding activities. Thus, our data suggest that commercially available tocotrienols inhibits cell growth, migration, and tumor cell invasiveness via downregulation of Notch 1 and NF-κB while inducing apoptosis. Hence, these commercially available tocotrienol-rich mixture could potentially be an effective supplementation for lung cancer prevention. Keywords: vitamin E, lung cancer, tocotrienol, NF-KB, apoptosis, proliferation, Notch |
| first_indexed | 2024-04-12T20:10:35Z |
| format | Article |
| id | doaj.art-c35d46af1d624345a3571a5ecaa1d890 |
| institution | Directory Open Access Journal |
| issn | 1179-1489 |
| language | English |
| last_indexed | 2024-04-12T20:10:35Z |
| publishDate | 2017-12-01 |
| publisher | Dove Medical Press |
| record_format | Article |
| series | Nutrition and Dietary Supplements |
| spelling | doaj.art-c35d46af1d624345a3571a5ecaa1d8902022-12-22T03:18:16ZengDove Medical PressNutrition and Dietary Supplements1179-14892017-12-01Volume 910311436019Tocotrienol-rich mixture inhibits cell proliferation and induces apoptosis via down-regulation of the Notch-1/NF-κB pathways in NSCLC cellsRajasinghe LDGupta SVLichchavi D Rajasinghe, Smiti V Gupta Department of Nutrition and Food Science, Wayne State University, Detroit, MI, USA Abstract: Lung cancer is one of the leading causes of cancer deaths. Non-small cell lung cancer (NSCLC), with a 5-year survival rate of 5% at stage IIIB, accounts for 80%–85% of all lung cancers. Aberrant Notch-1 expressions have been reported in lung cancer patients and could potentially be a beneficial molecular/therapeutic target against NSCLC. Tocotrienols, isomers of vitamin E, have been shown to exhibit antitumor activity via inhibition of different signaling pathways in tumor cells. Previously, we reported that delta-tocotrienol downregulates Notch-1 via NF-κB. However, the pure isomers are presently not available in quantities required for animal or clinical studies. Therefore, the objective of this study was to investigate the interactions and effects of commercially available tocotrienols (a mixture of isomers) on the Notch-1 pathway in NSCLC, adenocarcinoma (A549) and squamous cell lung cancer (H520) cell lines. A dose-dependent decrease in all growth, cell migration, and tumor invasiveness was observed in both cancer cell lines with the addition of tocotrienols. A significant induction of apoptosis was also observed using Annexin V stain in flow cytometry analysis. Since tocotrienols significantly affected proliferation, apoptosis, migration, and invasiveness, reverse transcription polymerase chain reaction and Western blot analysis were used to explore the molecular mechanisms responsible for the regulations by testing the expression of Notch-1 and its downstream genes. A dose-dependent decrease in expression of proteins was observed in Notch-1, Hes-1, Survivin, and Bcl-XL. In addition, we found a mechanism linking the NF-κB pathway and Notch-1 down-regulation from NF-κB DNA-binding activities. Thus, our data suggest that commercially available tocotrienols inhibits cell growth, migration, and tumor cell invasiveness via downregulation of Notch 1 and NF-κB while inducing apoptosis. Hence, these commercially available tocotrienol-rich mixture could potentially be an effective supplementation for lung cancer prevention. Keywords: vitamin E, lung cancer, tocotrienol, NF-KB, apoptosis, proliferation, Notch https://www.dovepress.com/tocotrienol-rich-mixture-inhibits-cell-proliferation-and-induces-apopt-peer-reviewed-article-NDSTocotrienolsVitamin EProliferationApoptosisNF- κBNotch |
| spellingShingle | Rajasinghe LD Gupta SV Tocotrienol-rich mixture inhibits cell proliferation and induces apoptosis via down-regulation of the Notch-1/NF-κB pathways in NSCLC cells Nutrition and Dietary Supplements Tocotrienols Vitamin E Proliferation Apoptosis NF- κB Notch |
| title | Tocotrienol-rich mixture inhibits cell proliferation and induces apoptosis via down-regulation of the Notch-1/NF-κB pathways in NSCLC cells |
| title_full | Tocotrienol-rich mixture inhibits cell proliferation and induces apoptosis via down-regulation of the Notch-1/NF-κB pathways in NSCLC cells |
| title_fullStr | Tocotrienol-rich mixture inhibits cell proliferation and induces apoptosis via down-regulation of the Notch-1/NF-κB pathways in NSCLC cells |
| title_full_unstemmed | Tocotrienol-rich mixture inhibits cell proliferation and induces apoptosis via down-regulation of the Notch-1/NF-κB pathways in NSCLC cells |
| title_short | Tocotrienol-rich mixture inhibits cell proliferation and induces apoptosis via down-regulation of the Notch-1/NF-κB pathways in NSCLC cells |
| title_sort | tocotrienol rich mixture inhibits cell proliferation and induces apoptosis via down regulation of the notch 1 nf kappa b pathways in nsclc cells |
| topic | Tocotrienols Vitamin E Proliferation Apoptosis NF- κB Notch |
| url | https://www.dovepress.com/tocotrienol-rich-mixture-inhibits-cell-proliferation-and-induces-apopt-peer-reviewed-article-NDS |
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