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Park Y, Park K. Phytochemical Index and the Risk of Gastritis/Gastric Ulcer among Korean Adults: A Prospective Cohort Study. Nutrients 2024; 16:2514. [PMID: 39125393 PMCID: PMC11314585 DOI: 10.3390/nu16152514] [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: 06/26/2024] [Revised: 07/25/2024] [Accepted: 07/29/2024] [Indexed: 08/12/2024] Open
Abstract
Phytochemicals found in fruits, vegetables, and plant-based foods have potential protective effects against various diseases, including gastric disorders. This study aimed to analyze the longitudinal association between phytochemical intake and the risk of gastritis/gastric ulcer in Korean adults. This was a prospective cohort study, a community-based cohort conducted as part of the Korean Genome and Epidemiology Study, examining the association between phytochemical intake and the risk of gastritis/gastric ulcer in Korean adults. Dietary information was collected using a validated semi-quantitative food frequency questionnaire, and the phytochemical index (PI) was calculated. The study included 7377 Korean men and women aged 40-69 years without gastritis/gastric ulcer at baseline of the Korea Association Resource study in Korea. The incidence of gastritis/gastric ulcer was determined using a survey questionnaire administered by trained staff. Multivariate Cox proportional hazards regression was used to calculate the hazard ratio and 95% confidence interval to determine the association between PI and risk of gastritis/gastric ulcer. During the median follow-up period of 9.50 years, 729 cases were reported. The fully adjusted model showed a significantly lower risk of gastritis/gastric ulcer in the highest PI quartile compared to the lowest (hazard ratio: 0.78, 95% confidence interval: 0.61-0.98), and this association was linear (p for trend = 0.01). This research indicates that incorporating foods abundant in phytochemicals into one's diet could be associated with a reduced risk of developing gastritis/gastric ulcers. These findings underscore the importance of further investigating the role of phytochemical-rich diets in gastrointestinal health, as demonstrated in this study.
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Affiliation(s)
| | - Kyong Park
- Department of Food and Nutrition, Yeungnam University, Gyeongsan 38541, Republic of Korea;
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Chaudhuri R, Samanta A, Saha P, Ghosh S, Sinha D. The Potential of Epigallocatechin Gallate in Targeting Cancer Stem Cells: A Comprehensive Review. Curr Med Chem 2024; 31:5255-5280. [PMID: 38243984 DOI: 10.2174/0109298673281666231227053726] [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: 09/13/2023] [Revised: 11/17/2023] [Accepted: 11/30/2023] [Indexed: 01/22/2024]
Abstract
The dreadful scenario of cancer prevails due to the presence of cancer stem cells (CSCs), which contribute to tumor growth, metastasis, invasion, resistance to chemo- and radiotherapy, and recurrence. CSCs are a small subpopulation of cells within the tumor that are characterized by self-renewal capability and have the potential to manifest heterogeneous lineages of cancer cells that constitute the tumor. The major bioactive green tea polyphenol (-)-epigallocatechin gallate (EGCG) has been fruitful in downgrading cancer stemness signaling and CSC biomarkers in cancer progression. EGCG has been evidenced to maneuver extrinsic and intrinsic apoptotic pathways in order to decrease the viability of CSCs. Cancer stemness is intricately related to epithelial-mesenchymal transition (EMT), metastasis and therapy resistance, and EGCG has been evidenced to regress all these CSC-related effects. By inhibiting CSC characteristics EGCG has also been evidenced to sensitize the tumor cells to radiotherapy and chemotherapy. However, the use of EGCG in in vitro and in vivo cancer models raises concern about its bioavailability, stability and efficacy against spheroids raised from parental cells. Therefore, novel nano formulations of EGCG and adjuvant therapy of EGCG with other phytochemicals or drugs or small molecules may have a better prospect in targeting CSCs. However, extensive clinical research is still awaited to elucidate a full proof impact of EGCG in cancer therapy.
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Affiliation(s)
- Rupa Chaudhuri
- Department of Receptor Biology and Tumor Metastasis, Chittaranjan National Cancer Institute, Kolkata, 700026, India
| | - Anurima Samanta
- Department of Receptor Biology and Tumor Metastasis, Chittaranjan National Cancer Institute, Kolkata, 700026, India
| | - Priyanka Saha
- Department of Receptor Biology and Tumor Metastasis, Chittaranjan National Cancer Institute, Kolkata, 700026, India
| | - Sukanya Ghosh
- Department of Receptor Biology and Tumor Metastasis, Chittaranjan National Cancer Institute, Kolkata, 700026, India
| | - Dona Sinha
- Department of Receptor Biology and Tumor Metastasis, Chittaranjan National Cancer Institute, Kolkata, 700026, India
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Sahadevan R, Binoy A, Vechalapu SK, Nanjan P, Sadhukhan S. In situ global proteomics profiling of EGCG targets using a cell-permeable and Click-able bioorthogonal probe. Int J Biol Macromol 2023; 237:123991. [PMID: 36907293 DOI: 10.1016/j.ijbiomac.2023.123991] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 03/01/2023] [Accepted: 03/05/2023] [Indexed: 03/12/2023]
Abstract
Despite possessing a wide spectrum of biological activities, molecular targets of EGCG remain elusive and as a result, its precise mode of action is still unknown. Herein, we have developed a novel cell-permeable and Click-able bioorthogonal probe for EGCG, YnEGCG for in situ detection and identification of its interacting proteins. The strategic structural modification on YnEGCG allowed it to retain innate biological activities of EGCG (IC50 59.52 ± 1.14 μM and 9.07 ± 0.01 μM for cell viability and radical scavenging activity, respectively). Chemoproteomics profiling identified 160 direct EGCG targets, with H:L ratio ≥ 1.10 from the list of 207 proteins, including multiple new proteins that were previously unknown. The targets were broadly distributed in various subcellular compartments suggesting a polypharmacological mode of action of EGCG. GO analysis revealed that the primary targets belonged to the enzymes that regulate key metabolic processes including glycolysis and energy homeostasis, also the cytoplasm (36 %) and mitochondria (15.6 %) contain the majority of EGCG targets. Further, we validated that EGCG interactome was closely associated with apoptosis indicating its role in inducing toxicity in cancer cells. For the first time, this in situ chemoproteomics approach could identify a direct and specific EGCG interactome under physiological conditions in an unbiased manner.
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Affiliation(s)
- Revathy Sahadevan
- Department of Chemistry, Indian Institute of Technology Palakkad, Kerala, India
| | - Anupama Binoy
- Department of Chemistry, Indian Institute of Technology Palakkad, Kerala, India
| | - Sai K Vechalapu
- Department of Chemistry, Indian Institute of Technology Kanpur, Uttar Pradesh, India
| | - Pandurangan Nanjan
- Department of Chemistry, Indian Institute of Technology Palakkad, Kerala, India
| | - Sushabhan Sadhukhan
- Department of Chemistry, Indian Institute of Technology Palakkad, Kerala, India; Physical & Chemical Biology Laboratory, Indian Institute of Technology Palakkad, Kerala, India; Department of Biological Sciences & Engineering, Indian Institute of Technology Palakkad, Kerala, India.
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Datta S, Ghosh S, Bishayee A, Sinha D. Flexion of Nrf2 by tea phytochemicals: A review on the chemopreventive and chemotherapeutic implications. Pharmacol Res 2022; 182:106319. [PMID: 35732198 DOI: 10.1016/j.phrs.2022.106319] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Revised: 06/16/2022] [Accepted: 06/16/2022] [Indexed: 01/11/2023]
Abstract
Nuclear factor erythroid 2 [NF-E2]-related factor 2 (Nrf2), the redox-sensitive transcription factor, plays a key role in stress-defense and detoxification. Nrf2 is tightly controlled by its negative regulator cum sensor Kelch-[ECH]-associated protein 1 (Keap1). Nrf2 is well known for its dual nature owing to its cancer preventive and cancer promoting abilities. Modulation of this biphasic nature of Nrf2 signaling by phytochemicals may be a potential cancer preventive and anticancer therapeutic strategy. Phytocompounds may either act as Nrf2-activator or Nrf2-inhibitor depending on their differential concentration and varied cellular environment. Tea is not just the most popular global beverage with innumerable health-benefits but has well-established chemopreventive and chemotherapeutic effects. Various types of tea infusions contain a wide range of bioactive compounds, such as polyphenolic catechins and flavonols, which are endowed with potent antioxidant properties. Despite of their rapid biotransformation and poor bioavailability, regular tea consumption is risk-reductive for several cancer forms. Tea catechins show their dual Nrf2-modulatory effect by directly acting on Nrf2-Keap1 or their upstream regulators and downstream effectors in a highly case-specific manner. In this review, we have tried to present a comprehensive evaluation of the Nrf2-mediated chemopreventive and chemotherapeutic applications of tea in various preclinical cancer models, the Nrf2-modulatory mechanisms, and the limitations which need to be addressed in future research.
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Affiliation(s)
- Suchisnigdha Datta
- Department of Receptor Biology and Tumor Metastasis, Chittaranjan National Cancer Institute, Kolkata - 700 026, West Bengal, India
| | - Sukanya Ghosh
- Department of Receptor Biology and Tumor Metastasis, Chittaranjan National Cancer Institute, Kolkata - 700 026, West Bengal, India
| | - Anupam Bishayee
- College of Osteopathic Medicine, Lake Erie College of Osteopathic Medicine, Bradenton, FL 34211, USA.
| | - Dona Sinha
- Department of Receptor Biology and Tumor Metastasis, Chittaranjan National Cancer Institute, Kolkata - 700 026, West Bengal, India.
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Lee TG, Kim Y, Jung W, Kim MK, Chong Y. An Amide Analog of (−)‐Epigallocatechin Gallate Shows Preferential Cytotoxicity toward
Triple‐Negative
Breast Cancer Cells. B KOREAN CHEM SOC 2020. [DOI: 10.1002/bkcs.12007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Tae Gum Lee
- Department of Bioscience and Biotechnology, Bio/Molecular Informatics CenterKonkuk University 120 Neungdong‐ro, Gwangjin‐gu, Seoul 05029 South Korea
| | - Yulim Kim
- Department of Bioscience and Biotechnology, Bio/Molecular Informatics CenterKonkuk University 120 Neungdong‐ro, Gwangjin‐gu, Seoul 05029 South Korea
| | - Woong Jung
- Department of Emergency MedicineKyung Hee University Hospital at Gangdong Seoul 134‐727 South Korea
| | - Mi Kyoung Kim
- Department of Bioscience and Biotechnology, Bio/Molecular Informatics CenterKonkuk University 120 Neungdong‐ro, Gwangjin‐gu, Seoul 05029 South Korea
| | - Youhoon Chong
- Department of Bioscience and Biotechnology, Bio/Molecular Informatics CenterKonkuk University 120 Neungdong‐ro, Gwangjin‐gu, Seoul 05029 South Korea
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Filippini T, Malavolti M, Borrelli F, Izzo AA, Fairweather-Tait SJ, Horneber M, Vinceti M. Green tea (Camellia sinensis) for the prevention of cancer. Cochrane Database Syst Rev 2020; 3:CD005004. [PMID: 32118296 PMCID: PMC7059963 DOI: 10.1002/14651858.cd005004.pub3] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND This review is an update of a previously published review in the Cochrane Database of Systematic Reviews (2009, Issue 3).Tea is one of the most commonly consumed beverages worldwide. Teas from the plant Camellia sinensis can be grouped into green, black and oolong tea, and drinking habits vary cross-culturally. C sinensis contains polyphenols, one subgroup being catechins. Catechins are powerful antioxidants, and laboratory studies have suggested that these compounds may inhibit cancer cell proliferation. Some experimental and nonexperimental epidemiological studies have suggested that green tea may have cancer-preventative effects. OBJECTIVES To assess possible associations between green tea consumption and the risk of cancer incidence and mortality as primary outcomes, and safety data and quality of life as secondary outcomes. SEARCH METHODS We searched eligible studies up to January 2019 in CENTRAL, MEDLINE, Embase, ClinicalTrials.gov, and reference lists of previous reviews and included studies. SELECTION CRITERIA We included all epidemiological studies, experimental (i.e. randomised controlled trials (RCTs)) and nonexperimental (non-randomised studies, i.e. observational studies with both cohort and case-control design) that investigated the association of green tea consumption with cancer risk or quality of life, or both. DATA COLLECTION AND ANALYSIS Two or more review authors independently applied the study criteria, extracted data and assessed methodological quality of studies. We summarised the results according to diagnosis of cancer type. MAIN RESULTS In this review update, we included in total 142 completed studies (11 experimental and 131 nonexperimental) and two ongoing studies. This is an additional 10 experimental and 85 nonexperimental studies from those included in the previous version of the review. Eleven experimental studies allocated a total of 1795 participants to either green tea extract or placebo, all demonstrating an overall high methodological quality based on 'Risk of bias' assessment. For incident prostate cancer, the summary risk ratio (RR) in the green tea-supplemented participants was 0.50 (95% confidence interval (CI) 0.18 to 1.36), based on three studies and involving 201 participants (low-certainty evidence). The summary RR for gynaecological cancer was 1.50 (95% CI 0.41 to 5.48; 2 studies, 1157 participants; low-certainty evidence). No evidence of effect of non-melanoma skin cancer emerged (summary RR 1.00, 95% CI 0.06 to 15.92; 1 study, 1075 participants; low-certainty evidence). In addition, adverse effects of green tea extract intake were reported, including gastrointestinal disorders, elevation of liver enzymes, and, more rarely, insomnia, raised blood pressure and skin/subcutaneous reactions. Consumption of green tea extracts induced a slight improvement in quality of life, compared with placebo, based on three experimental studies. In nonexperimental studies, we included over 1,100,000 participants from 46 cohort studies and 85 case-control studies, which were on average of intermediate to high methodological quality based on Newcastle-Ottawa Scale 'Risk of bias' assessment. When comparing the highest intake of green tea with the lowest, we found a lower overall cancer incidence (summary RR 0.83, 95% CI 0.65 to 1.07), based on three studies, involving 52,479 participants (low-certainty evidence). Conversely, we found no association between green tea consumption and cancer-related mortality (summary RR 0.99, 95% CI 0.91 to 1.07), based on eight studies and 504,366 participants (low-certainty evidence). For most of the site-specific cancers we observed a decreased RR in the highest category of green tea consumption compared with the lowest one. After stratifying the analysis according to study design, we found strongly conflicting results for some cancer sites: oesophageal, prostate and urinary tract cancer, and leukaemia showed an increased RR in cohort studies and a decreased RR or no difference in case-control studies. AUTHORS' CONCLUSIONS Overall, findings from experimental and nonexperimental epidemiological studies yielded inconsistent results, thus providing limited evidence for the beneficial effect of green tea consumption on the overall risk of cancer or on specific cancer sites. Some evidence of a beneficial effect of green tea at some cancer sites emerged from the RCTs and from case-control studies, but their methodological limitations, such as the low number and size of the studies, and the inconsistencies with the results of cohort studies, limit the interpretability of the RR estimates. The studies also indicated the occurrence of several side effects associated with high intakes of green tea. In addition, the majority of included studies were carried out in Asian populations characterised by a high intake of green tea, thus limiting the generalisability of the findings to other populations. Well conducted and adequately powered RCTs would be needed to draw conclusions on the possible beneficial effects of green tea consumption on cancer risk.
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Affiliation(s)
- Tommaso Filippini
- University of Modena and Reggio Emilia, Research Center in Environmental, Nutritional and Genetic Epidemiology (CREAGEN), Department of Biomedical, Metabolic and Neural Sciences, Via Campi 287, Modena, Italy, 41125
| | - Marcella Malavolti
- University of Modena and Reggio Emilia, Research Center in Environmental, Nutritional and Genetic Epidemiology (CREAGEN), Department of Biomedical, Metabolic and Neural Sciences, Via Campi 287, Modena, Italy, 41125
| | - Francesca Borrelli
- University of Naples 'Federico II', Department of Pharmacy, School of Medicine and Surgery, Via D Montesano 49, Naples, Italy, 80131
| | - Angelo A Izzo
- University of Naples 'Federico II', Department of Pharmacy, School of Medicine and Surgery, Via D Montesano 49, Naples, Italy, 80131
| | | | - Markus Horneber
- Paracelsus Medical University, Klinikum Nuremberg, Department of Internal Medicine, Division of Oncology and Hematology, Prof.-Ernst-Nathan-Str. 1, Nuremberg, Germany, D-90419
| | - Marco Vinceti
- University of Modena and Reggio Emilia, Research Center in Environmental, Nutritional and Genetic Epidemiology (CREAGEN), Department of Biomedical, Metabolic and Neural Sciences, Via Campi 287, Modena, Italy, 41125
- Boston University School of Public Health, Department of Epidemiology, 715 Albany Street, Boston, USA, MA 02118
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An Improved Weighted Partial Least Squares Method Coupled with Near Infrared Spectroscopy for Rapid Determination of Multiple Components and Anti-Oxidant Activity of Pu-Erh Tea. Molecules 2018; 23:molecules23051058. [PMID: 29724034 PMCID: PMC6102534 DOI: 10.3390/molecules23051058] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Revised: 04/24/2018] [Accepted: 04/25/2018] [Indexed: 01/11/2023] Open
Abstract
Background: Pu-erh tea is a unique microbially fermented tea, which distinctive chemical constituents and activities are worthy of systematic study. Near infrared spectroscopy (NIR) coupled with suitable chemometrics approaches can rapidly and accurately quantitatively analyze multiple compounds in samples. Methods: In this study, an improved weighted partial least squares (PLS) algorithm combined with near infrared spectroscopy (NIR) was used to construct a fast calibration model for determining four main components, i.e., tea polyphenols, tea polysaccharide, total flavonoids, theanine content, and further determine the total antioxidant capacity of pu-erh tea. Results: The final correlation coefficients R square for tea polyphenols, tea polysaccharide, total flavonoids content, theanine content, and total antioxidant capacity were 0.8288, 0.8403, 0.8415, 0.8537 and 0.8682, respectively. Conclusions: The current study provided a comprehensive study of four main ingredients and activity of pu-erh tea, and demonstrated that NIR spectroscopy technology coupled with multivariate calibration analysis could be successfully applied to pu-erh tea quality assessment.
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Rogers J, Perkins I, van Olphen A, Burdash N, Klein TW, Friedman H. Epigallocatechin Gallate Modulates Cytokine Production by Bone Marrow-Derived Dendritic Cells Stimulated with Lipopolysaccharide or Muramyldipeptide, or Infected with Legionella pneumophila. Exp Biol Med (Maywood) 2016; 230:645-51. [PMID: 16179732 DOI: 10.1177/153537020523000906] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The primary polyphenol in green tea extract is the catechin epigallocatechin gallate (EGCG). Various studies have shown significant suppressive effects of catechin on mammalian cells, either tumor or normal cells, including lymphoid cells. Previous studies from this laboratory reported that EGCG has marked suppressive activity on murine macrophages infected with the intracellular bacterium Legionella pneumophila (Lp), an effect mediated by enhanced production of both tumor necrosis factor-α (TNF-α) and γ-interferon (IFN-γ). In the present study, primary murine bone marrow (BM)-derived dendritic cells (DCs), a phagocytic monocytic cell essential for innate immunity to intracellular microorganisms, such as Lp, were stimulated in vitro with the microbial stimulant lipopolysaccharide (LPS) from gram-negative bacteria, the cell wall component from gram-positive bacteria muramyldipeptide (MDP) or infected with Lp. Production of the T helper cell (Th1)-activating cytokine, interleukin-12 (IL-12) and the proinflammatory cytokine, tumor necrosis factor-α (TNF-α), produced mainly by phagocytic cells and important for antimicrobial immunity, was determined in cell culture supernatants by enzyme-linked immunosorbent assay (ELISA). Treatment of the cells with EGCG inhibited, in a dose-dependent manner, production of IL-12. In contrast, enhanced production of TNF-α occurred in a dose-dependent manner in the DC cultures stimulated with either soluble bacterial product or infected with Lp. Thus, the results of this study show that the EGCG catechin has a marked effect in modulating production of these immunoregulatory cytokines in stimulated DCs, which are important for antimicrobial immunity, especially innate immunity. Further studies are necessary to characterize the physiologic function of the effect of EGCG on TNF-α and IL-12 during Lp infection, and the mechanisms involved.
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Affiliation(s)
- James Rogers
- Department of Medical Microbiology and Immunology, University of South Florida, Tampa, FL 33612, USA
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Bioguided Fraction and Isolation of the Antitumor Components from Phyllanthus niruri L. BIOMED RESEARCH INTERNATIONAL 2016; 2016:9729275. [PMID: 27777954 PMCID: PMC5061927 DOI: 10.1155/2016/9729275] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 08/18/2016] [Accepted: 08/29/2016] [Indexed: 01/11/2023]
Abstract
Phyllanthus niruri L., a well-known medicinal plant, has been used as a folk antitumor remedy in the worldwide scale. However, the antitumor components in P. niruri have not been reported. In order to verify the antitumor components of P. niruri and the plants which have the high content of these components, we isolated the antitumor components with bioguided fraction and isolation, by different chromatographic methods from the ethyl acetate fraction of P. niruri., and identified them as ethyl brevifolincarboxylate and corilagin by 1H-NMR, 13C-NMR, 2D-NMR, and mass spectrometric analyses. Cell cytotoxicity assays showed that corilagin has broad-spectrum antitumor activity, a better antitumor potential, and lower toxicity in normal cells. Besides, the coefficient of drug interaction (CDI) of 10 μM corilagin and 20 μM cDDP reached up to 0.77, which means corilagin can promote the antitumor activity of cDDP. Furthermore, by the extensive screening among 10 species of plants reported to contain corilagin, we found that Dimocarpus longan Lour. has the maximum content of corilagin. In conclusion, corilagin is the major active antitumor composition in P. niruri. L. on HCC cells and has high content in D. longan.
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Granja A, Pinheiro M, Reis S. Epigallocatechin Gallate Nanodelivery Systems for Cancer Therapy. Nutrients 2016; 8:nu8050307. [PMID: 27213442 PMCID: PMC4882719 DOI: 10.3390/nu8050307] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 05/10/2016] [Accepted: 05/12/2016] [Indexed: 12/31/2022] Open
Abstract
Cancer is one of the leading causes of morbidity and mortality all over the world. Conventional treatments, such as chemotherapy, are generally expensive, highly toxic and lack efficiency. Cancer chemoprevention using phytochemicals is emerging as a promising approach for the treatment of early carcinogenic processes. (−)-Epigallocatechin-3-gallate (EGCG) is the major bioactive constituent in green tea with numerous health benefits including anti-cancer activity, which has been intensively studied. Besides its potential for chemoprevention, EGCG has also been shown to synergize with common anti-cancer agents, which makes it a suitable adjuvant in chemotherapy. However, limitations in terms of stability and bioavailability have hampered its application in clinical settings. Nanotechnology may have an important role in improving the pharmacokinetic and pharmacodynamics of EGCG. Indeed, several studies have already reported the use of nanoparticles as delivery vehicles of EGCG for cancer therapy. The aim of this article is to discuss the EGCG molecule and its associated health benefits, particularly its anti-cancer activity and provide an overview of the studies that have employed nanotechnology strategies to enhance EGCG’s properties and potentiate its anti-tumoral activity.
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Affiliation(s)
- Andreia Granja
- UCIBIO/REQUIMTE, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal.
| | - Marina Pinheiro
- UCIBIO/REQUIMTE, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal.
| | - Salette Reis
- UCIBIO/REQUIMTE, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal.
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Ronholm J, Lau F, Banerjee SK. Emerging Seafood Preservation Techniques to Extend Freshness and Minimize Vibrio Contamination. Front Microbiol 2016; 7:350. [PMID: 27047466 PMCID: PMC4801881 DOI: 10.3389/fmicb.2016.00350] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Accepted: 03/07/2016] [Indexed: 01/21/2023] Open
Abstract
Globally, the popularity of seafood consumption is increasing exponentially. To meet the demands of a growing market, the seafood industry has increasingly been innovating ways to keep their products fresh and safe while increasing production. Marine environments harbor several species of indigenous microorganisms, some of which, including Vibrio spp., may be harmful to humans, and all of which are part of the natural microbiota of the seafood. After harvest, seafood products are often shipped over large geographic distances, sometimes for prolonged periods, during which the food must stay fresh and pathogen proliferation must be minimized. Upon arrival there is often a strong desire, arising from both culinary and nutritional considerations, to consume seafood products raw, or minimally cooked. This supply chain along with popular preferences have increased challenges for the seafood industry. This has resulted in a desire to develop methodologies that reduce pathogenic and spoilage organisms in seafood items to comply with regulations and result in minimal changes to the taste, texture, and nutritional content of the final product. This mini-review discusses and compares several emerging technologies, such as treatment with plant derived natural compounds, phage lysis, high-pressure processing, and irradiation for their ability to control pathogenic vibrios, limit the growth of spoilage organisms, and keep the desired organoleptic properties of the seafood product intact.
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Affiliation(s)
- Jennifer Ronholm
- Microbiology Research Division, Bureau of Microbial Hazards, Food Directorate, Health Products and Food Branch, Health Canada Ottawa, ON, Canada
| | - Fiona Lau
- Microbiology Research Division, Bureau of Microbial Hazards, Food Directorate, Health Products and Food Branch, Health CanadaOttawa, ON, Canada; University of OttawaOttawa, ON, Canada
| | - Swapan K Banerjee
- Microbiology Research Division, Bureau of Microbial Hazards, Food Directorate, Health Products and Food Branch, Health Canada Ottawa, ON, Canada
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Sagar M, Pathak RK, Pandey RK, Singh DB, Pandey N, Gupta MK. Binding affinity analysis and ADMET prediction of epigallocatechine gallate (EGCG) derivatives for AP-1 protein: a drug target for liver cancer. ACTA ACUST UNITED AC 2014. [DOI: 10.1007/s13721-014-0066-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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13
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Ko MJ, Cheigh CI, Chung MS. Optimization of subcritical water extraction of flavanols from green tea leaves. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2014; 62:6828-6833. [PMID: 24918863 DOI: 10.1021/jf5012006] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The subcritical-water extraction (SWE) of six kinds of flavanols from green tea leaves and the effect of extraction conditions were investigated by varying the temperature and time. The maximum yield of total flavanols, 71.36 ± 4.23 mg/g green tea leaves (mean ± SD), was obtained under extraction temperature/time conditions of 150 °C/5 min. The efficiency of SWE for total flavanols was slightly higher than that of the conventional extraction solvents such as methanol and ethanol. The extraction of flavanols via SWE was specifically adequate for epimer structures such as catechin, catechin gallate, and gallocatechin gallate due to the epimerization of epicatechins. The extraction efficiency of epimers was increased at temperatures up to 170 °C, whereas that of epicatechins was decreased. Thus, most epicatechins were converted to epimers during SWE, leading to some flavanol destruction at high temperatures, except when a short extraction time of 5 min was used.
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Affiliation(s)
- Min-Jung Ko
- Department of Food Science and Engineering, Ewha Womans University , Seoul 120-750, South Korea
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Sonoda JI, Ikeda R, Baba Y, Narumi K, Kawachi A, Tomishige E, Nishihara K, Takeda Y, Yamada K, Sato K, Motoya T. Green tea catechin, epigallocatechin-3-gallate, attenuates the cell viability of human non-small-cell lung cancer A549 cells via reducing Bcl-xL expression. Exp Ther Med 2014; 8:59-63. [PMID: 24944597 PMCID: PMC4061191 DOI: 10.3892/etm.2014.1719] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Accepted: 04/29/2014] [Indexed: 11/24/2022] Open
Abstract
Clinical and epidemiological studies have indicated that the consumption of green tea has a number of beneficial effects on health. Epigallocatechin-3-gallate (EGCg), the major polyphenolic compound present in green tea, has received much attention as an active ingredient. Among the numerous promising profiles of EGCg, the present study focused on the anticancer effects. Apoptosis induced by EGCg and subsequent cell growth suppression have been demonstrated in a number of cell culture studies. However, the underlying mechanism of apoptotic cell death remains unclear. Thus, the aim of the present study was to identify the major molecule that mediates proapoptotic cell death by EGCg. The effect of EGCg on cell proliferation and the induction of mRNA that modulates apoptotic cell death was evaluated in the A549 human non-small-cell lung cancer cell line. In addition, morphological changes were assessed by microscopy in A549 cells that had been treated with 100 μM EGCg for 24 h. The MTT assay revealed that cell proliferation was significantly reduced by EGCg in a dose-dependent manner (3–100 μM). The mRNA expression level of B-cell lymphoma-extra large (Bcl-xL) was decreased in A549 cells following 24 h incubation with 100 μM EGCg. Therefore, the results indicated that the inhibition of cell proliferation by EGCg may be achieved via suppressing the expression of the cell death-inhibiting gene, Bcl-xL.
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Affiliation(s)
- Jun-Ichiro Sonoda
- First Department of Clinical Pharmacy, School of Pharmaceutical Sciences, Kyushu University of Health & Welfare, Nobeoka, Miyazaki 882-8508, Japan
| | - Ryuji Ikeda
- Department of Clinical Pharmacy and Pharmacology, Graduate School of Medical and Dental Sciences, Kagoshima University, Sakuragaoka, Kagoshima 890-8520, Japan
| | - Yasutaka Baba
- Department of Radiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Sakuragaoka, Kagoshima 890-8520, Japan
| | - Keiko Narumi
- First Department of Clinical Pharmacy, School of Pharmaceutical Sciences, Kyushu University of Health & Welfare, Nobeoka, Miyazaki 882-8508, Japan
| | - Akio Kawachi
- First Department of Clinical Pharmacy, School of Pharmaceutical Sciences, Kyushu University of Health & Welfare, Nobeoka, Miyazaki 882-8508, Japan
| | - Erisa Tomishige
- First Department of Clinical Pharmacy, School of Pharmaceutical Sciences, Kyushu University of Health & Welfare, Nobeoka, Miyazaki 882-8508, Japan
| | - Kazuya Nishihara
- First Department of Clinical Pharmacy, School of Pharmaceutical Sciences, Kyushu University of Health & Welfare, Nobeoka, Miyazaki 882-8508, Japan
| | - Yasuo Takeda
- Department of Clinical Pharmacy and Pharmacology, Graduate School of Medical and Dental Sciences, Kagoshima University, Sakuragaoka, Kagoshima 890-8520, Japan
| | - Katsushi Yamada
- Department of Clinical Pharmacology, Faculty of Pharmaceutical Science, Nagasaki International University, Sasebo, Nagasaki 859-3298, Japan
| | - Keizo Sato
- Department of Clinical Biochemistry, School of Pharmaceutical Sciences, Kyushu University of Health & Welfare, Nobeoka, Miyazaki 882-8508, Japan
| | - Toshiro Motoya
- First Department of Clinical Pharmacy, School of Pharmaceutical Sciences, Kyushu University of Health & Welfare, Nobeoka, Miyazaki 882-8508, Japan
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Cancer prevention trial of a synergistic mixture of green tea concentrate plus Capsicum (CAPSOL-T) in a random population of subjects ages 40-84. Clin Proteomics 2014; 11:2. [PMID: 24393573 PMCID: PMC3901999 DOI: 10.1186/1559-0275-11-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Accepted: 12/10/2013] [Indexed: 01/01/2023] Open
Abstract
Background Experts agree that one of the more promising strategies in cancer management is early detection coupled with early intervention. In this study, we evaluated an early cancer detection strategy of cancer presence based on serum levels of the cancer-specific transcript variants of ENOX2 in serum coupled with an ENOX2-targeted nutraceutical preparation of green tea concentrate plus Capsicum (Capsol-T®) as a strategy of Curative Prevention® involving early detection coupled with early intervention in early stage cancer when in its most susceptible and manageable stages. Experimental design One hundred ten (110) subjects were tested for cancer presence using the ONCOblot® Tissue of Origin 2-D gel/western blot protocol for detection of serum presence of transcript variants of the ENOX2 protein. Subjects testing positive for ENOX2 received 350 mg of Capsol-T® in capsule form every 4 h including during the night for periods of at least 3 to 6 months or longer after which they were again tested for ENOX2 presence using the ONCOblot® Tissue of Origin Cancer Test protocol. Results Of the 110 subjects, both male and female, ages 40 to 84, with no evidence of clinical symptoms of cancer, 40% were positive for ENOX2 presence in the ONCOblot® Tissue of Origin Cancer Test. After completion of 3 to 17 months of Capsol-T® use, 94% of subjects subsequently tested negative for ENOX2 presence. Conclusions Oral Capsol-T® is well tolerated and, for ENOX2 presence in serum in the absence of clinical cancer symptoms, is consistently effective in reducing the serum ENOX2 levels to below detectable limits.
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Gaur S, Agnihotri R. Green tea: A novel functional food for the oral health of older adults. Geriatr Gerontol Int 2013; 14:238-50. [DOI: 10.1111/ggi.12194] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/15/2013] [Indexed: 12/19/2022]
Affiliation(s)
- Sumit Gaur
- Department of Pedodontics and Preventive Dentistry; Manipal College of Dental Sciences, Manipal University; Manipal India
| | - Rupali Agnihotri
- Department of Periodontology; Manipal College of Dental Sciences, Manipal University; Manipal India
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Dong L, Zhu J, Li X, Li J. Effect of tea polyphenols on the physical and chemical characteristics of dried-seasoned squid (Dosidicus gigas) during storage. Food Control 2013. [DOI: 10.1016/j.foodcont.2012.10.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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18
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Targeting sonic hedgehog signaling by compounds and derivatives from natural products. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2013; 2013:748587. [PMID: 23762158 PMCID: PMC3671665 DOI: 10.1155/2013/748587] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Accepted: 04/30/2013] [Indexed: 01/01/2023]
Abstract
Cancer stem cells (CSCs) are a major cause of cancer treatment failure, relapse, and drug resistance and are known to be responsible for cancer cell invasion and metastasis. The Sonic hedgehog (Shh) signaling pathway is crucial to embryonic development. Intriguingly, the aberrant activation of the Shh pathway plays critical roles in developing CSCs and leads to angiogenesis, migration, invasion, and metastasis. Natural compounds and chemical structure modified derivatives from complementary and alternative medicine have received increasing attention as cancer chemopreventives, and their antitumor effects have been demonstrated both in vitro and in vivo. However, reports for their bioactivity against CSCs and specifically targeting Shh signaling remain limited. In this review, we summarize investigations of the compounds cyclopamine, curcumin, epigallocatechin-3-gallate, genistein, resveratrol, zerumbone, norcantharidin, and arsenic trioxide, with a focus on Shh signaling blockade. Given that Shh signaling antagonism has been clinically proven as effective strategy against CSCs, this review may be exploitable for development of novel anticancer agents from complementary and alternative medicine.
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Herbacetin induces apoptosis in HepG2 cells: Involvements of ROS and PI3K/Akt pathway. Food Chem Toxicol 2013; 51:426-33. [DOI: 10.1016/j.fct.2012.09.036] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Revised: 09/28/2012] [Accepted: 09/29/2012] [Indexed: 12/11/2022]
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Fujiki H, Imai K, Nakachi K, Shimizu M, Moriwaki H, Suganuma M. Challenging the effectiveness of green tea in primary and tertiary cancer prevention. J Cancer Res Clin Oncol 2012; 138:1259-70. [PMID: 22699930 DOI: 10.1007/s00432-012-1250-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Accepted: 05/22/2012] [Indexed: 12/17/2022]
Abstract
PURPOSE Drinking green tea daily is part of Japanese culture, and various studies have revealed that green tea is a cancer preventive. We here review our progress in cancer prevention with green tea on 12 main topics, from basic to clinical level. TOPICS AND METHODS: Biochemical and biological studies of green tea catechins, a prospective cohort study, preclinical safety trials with tablets of green tea extract, double-blind randomized clinical phase II prevention trial for recurrence of colorectal adenomas, and synergistically enhanced inhibition by the combination of green tea catechins and anticancer drugs. All results were significant, including human studies with informed consent. RESULTS Drinking 10 Japanese-size cups of green tea per day delayed the cancer onset of humans 7 years for females. For tertiary cancer prevention, consuming 10 cups of green tea per day fortified by green tea tablets, 50 %, significantly prevented the recurrence of colorectal adenomas. A minimum effective amount of green tea catechins for cancer prevention was found in humans. In addition, the combination of green tea catechins and anticancer drugs engendered a new cancer therapeutic strategy. CONCLUSION The consumption of 10 Japanese-size cups of green tea per day is a significant factor in primary cancer prevention for the general population, and the preventive effect on recurrence of colorectal adenomas in patients is vital evidence in tertiary cancer prevention.
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Affiliation(s)
- Hirota Fujiki
- Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Tokushima 770-8514, Japan.
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21
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Masek A, Chrzescijanska E, Kosmalska A, Zaborski M. Antioxidant activity determination in Sencha and Gun Powder green tea extracts with the application of voltammetry and UV-VIS spectrophotometry. CR CHIM 2012. [DOI: 10.1016/j.crci.2012.01.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Kumar N, Crocker T, Smith T, Connors S, Pow-Sang J, Spiess PE, Egan K, Quinn G, Schell M, Sebti S, Kazi A, Chuang T, Salup R, Helal M, Zagaja G, Trabulsi E, McLarty J, Fazili T, Williams CR, Schreiber F, Anderson K. Prostate Cancer Chemoprevention Targeting Men with High-Grade Prostatic Intraepithelial Neoplasia (HGPIN) and Atypical Small Acinar Proliferation (ASAP): Model for Trial Design and Outcome Measures. ACTA ACUST UNITED AC 2012; 2. [PMID: 24533253 PMCID: PMC3924733 DOI: 10.4172/jctr.1000105] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In spite of the large number of nutrient-derived agents demonstrating promise as potential chemopreventive agents, most have failed to prove effectiveness in clinical trials. Critical requirements for moving nutrient-derived agents to recommendation for clinical use include adopting a systematic, molecular-mechanism based approach and utilizing the same ethical and rigorous methods such as are used to evaluate other pharmacological agents. Preliminary data on a mechanistic rationale for chemoprevention activity as observed from epidemiological, in vitro and preclinical studies, phase I data of safety in suitable cohorts, duration of intervention based on time to progression of preneoplastic disease to cancer and the use of a valid panel of biomarkers representing the hypothesized carcinogenesis pathway for measuring efficacy must inform the design of phase II clinical trials. The goal of this paper is to provide a model for evaluating a well characterized agent- Polyphenon E- in a phase II clinical trial of prostate cancer chemoprevention.
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Affiliation(s)
- Nagi Kumar
- Departments of Epidemiology, Health Outcomes and Behavior, Biostatistics, H. Lee Moffitt Cancer Center & Research Institute, University of South Florida College of Medicine, Florida, USA ; Oncological Sciences, University of South Florida College of Medicine, Tampa Florida
| | - Theresa Crocker
- Departments of Epidemiology, Health Outcomes and Behavior, Biostatistics, H. Lee Moffitt Cancer Center & Research Institute, University of South Florida College of Medicine, Florida, USA
| | - Tiffany Smith
- Departments of Epidemiology, Health Outcomes and Behavior, Biostatistics, H. Lee Moffitt Cancer Center & Research Institute, University of South Florida College of Medicine, Florida, USA
| | - Shahnjayla Connors
- Departments of Epidemiology, Health Outcomes and Behavior, Biostatistics, H. Lee Moffitt Cancer Center & Research Institute, University of South Florida College of Medicine, Florida, USA ; Oncological Sciences, University of South Florida College of Medicine, Tampa Florida
| | - Julio Pow-Sang
- Departments of Epidemiology, Health Outcomes and Behavior, Biostatistics, H. Lee Moffitt Cancer Center & Research Institute, University of South Florida College of Medicine, Florida, USA ; Oncological Sciences, University of South Florida College of Medicine, Tampa Florida
| | - Philippe E Spiess
- Departments of Epidemiology, Health Outcomes and Behavior, Biostatistics, H. Lee Moffitt Cancer Center & Research Institute, University of South Florida College of Medicine, Florida, USA ; Oncological Sciences, University of South Florida College of Medicine, Tampa Florida
| | - Kathleen Egan
- Departments of Epidemiology, Health Outcomes and Behavior, Biostatistics, H. Lee Moffitt Cancer Center & Research Institute, University of South Florida College of Medicine, Florida, USA ; Oncological Sciences, University of South Florida College of Medicine, Tampa Florida
| | - Gwen Quinn
- Departments of Epidemiology, Health Outcomes and Behavior, Biostatistics, H. Lee Moffitt Cancer Center & Research Institute, University of South Florida College of Medicine, Florida, USA ; Oncological Sciences, University of South Florida College of Medicine, Tampa Florida
| | - Michael Schell
- Departments of Epidemiology, Health Outcomes and Behavior, Biostatistics, H. Lee Moffitt Cancer Center & Research Institute, University of South Florida College of Medicine, Florida, USA ; Oncological Sciences, University of South Florida College of Medicine, Tampa Florida
| | - Said Sebti
- Departments of Epidemiology, Health Outcomes and Behavior, Biostatistics, H. Lee Moffitt Cancer Center & Research Institute, University of South Florida College of Medicine, Florida, USA ; Oncological Sciences, University of South Florida College of Medicine, Tampa Florida
| | - Aslam Kazi
- Departments of Epidemiology, Health Outcomes and Behavior, Biostatistics, H. Lee Moffitt Cancer Center & Research Institute, University of South Florida College of Medicine, Florida, USA ; Oncological Sciences, University of South Florida College of Medicine, Tampa Florida
| | - Tian Chuang
- Departments of Epidemiology, Health Outcomes and Behavior, Biostatistics, H. Lee Moffitt Cancer Center & Research Institute, University of South Florida College of Medicine, Florida, USA ; Oncological Sciences, University of South Florida College of Medicine, Tampa Florida
| | - Raoul Salup
- Oncological Sciences, University of South Florida College of Medicine, Tampa Florida ; James A. Haley V.A. Hospital, Tampa, FL
| | - Mohamed Helal
- Oncological Sciences, University of South Florida College of Medicine, Tampa Florida
| | | | | | - Jerry McLarty
- LSUHSC - Feist-Weiller Cancer Center, Shreveport, LA
| | | | | | - Fred Schreiber
- Watson Clinic - Center for Cancer Care & Research, Lakeland, FL
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Connors SK, Chornokur G, Kumar NB. New insights into the mechanisms of green tea catechins in the chemoprevention of prostate cancer. Nutr Cancer 2011; 64:4-22. [PMID: 22098273 DOI: 10.1080/01635581.2012.630158] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Prostate cancer is the most commonly diagnosed cancer and second most common cause of cancer deaths in American men. Its long latency, slow progression, and high incidence rate make prostate cancer ideal for targeted chemopreventative therapies. Therefore, chemoprevention studies and clinical trials are essential for reducing the burden of prostate cancer on society. Epidemiological studies suggest that tea consumption has protective effects against a variety of human cancers, including that of the prostate. Laboratory and clinical studies have demonstrated that green tea components, specifically the green tea catechin (GTC) epigallocatechin gallate, can induce apoptosis, suppress progression, and inhibit invasion and metastasis of prostate cancer. Multiple mechanisms are involved in the chemoprevention of prostate cancer with GTCs; understanding and refining models of fundamental molecular pathways by which GTCs modulate prostate carcinogenesis is essential to apply the utilization of green tea for the chemoprevention of prostate cancer in clinical settings. The objective of this article is to review and summarize the most current literature focusing on the major mechanisms of GTC chemopreventative action on prostate cancer from laboratory, in vitro, and in vivo studies, and clinical chemoprevention trials.
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Affiliation(s)
- Shahnjayla K Connors
- Department of Cancer Epidemiology, Division of Population Sciences, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida 33612, USA.
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Mohanpuria P, Kumar V, Ahuja PS, Yadav SK. Producing low-caffeine tea through post-transcriptional silencing of caffeine synthase mRNA. PLANT MOLECULAR BIOLOGY 2011; 76:523-34. [PMID: 21562910 DOI: 10.1007/s11103-011-9785-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2010] [Accepted: 05/02/2011] [Indexed: 05/24/2023]
Abstract
In this study, attempt has been made to produce a selected cultivar of tea with low-caffeine content using RNAi technology. The caffeine biosynthetic pathway in tea has been proposed to involve three N-methyltransferases such as xanthosine methyltransferase, 7-N-methylxanthine methyltransferase and 3, 7-dimethylxanthine methyltransferase. Last two steps of caffeine biosynthesis in tea have been known to be catalyzed by a bifunctional enzyme known as caffeine synthase. To suppress the caffeine synthesis in the selected tea [Camellia sinensis (L.) O. Kuntze] cv. Kangra jat, we isolated a partial fragment of caffeine synthase (CS) from the same cultivar and used to design RNAi construct (pFGC1008-CS). Somatic embryos were transformed with the developed construct using biolistic method. Transformed somatic embryos showed reduction in the levels of CS transcript expression as well as in caffeine content. Plants were regenerated from the transformed somatic embryos. Transgenic plants showed a significant suppression of CS transcript expression and also showed a reduction of 44-61% in caffeine and 46-67% in theobromine contents as compared to the controls. These results suggest that the RNAi construct developed here using a single partial fragment of CS gene reduced the expression of the targeted endogenous gene significantly. However, the reduction in theobromine content in addition to caffeine documented the involvement of this single CS in the catalysis of last two methyl transfer steps in caffeine biosynthesis of tea.
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Affiliation(s)
- Prashant Mohanpuria
- Biotechnology Division, Institute of Himalayan Bioresource Technology, CSIR, Palampur, 176061, HP, India
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26
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Ludwiczuk A, Saha A, Kuzuhara T, Asakawa Y. Bioactivity guided isolation of anticancer constituents from leaves of Alnus sieboldiana (Betulaceae). PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2011; 18:491-498. [PMID: 21111588 DOI: 10.1016/j.phymed.2010.10.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2010] [Revised: 08/30/2010] [Accepted: 10/07/2010] [Indexed: 05/30/2023]
Abstract
The leaves of the Japanese Alnus sieboldiana have been extracted with n-hexane and then with methanol. A bioactivity-guided approach based on MTT assay for growth inhibition and quantitative real-time PCR for TNF-α inhibitory activity was taken to identify the active compounds in EtOAc soluble fraction of the methanol extract. From this active fraction, seven compounds have been isolated and four compounds (pinosylvin, galangin, quercetin and methyl gallate) have been examined for their dose-response effect on the viability of A549 cells and on TNF-α inhibitory activity. Based on MTT assay, all of the four examined compounds inhibit growth of human lung cancer cells. Among four tested compounds only galangin (3,5,7-trihydroxyflavone) significantly inhibited TNF-α gene expression in A549 cells (IC₅₀ = 94 μM). Taken together, this finding suggests that galangin may be useful in cancer prevention.
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Affiliation(s)
- A Ludwiczuk
- Laboratory of Pharmaceutical Chemistry, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, 180 Yamaschiro-cho, Tokushima 770-8514, Japan
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27
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Li Y, Wicha MS, Schwartz SJ, Sun D. Implications of cancer stem cell theory for cancer chemoprevention by natural dietary compounds. J Nutr Biochem 2011; 22:799-806. [PMID: 21295962 DOI: 10.1016/j.jnutbio.2010.11.001] [Citation(s) in RCA: 125] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2010] [Revised: 10/09/2010] [Accepted: 11/03/2010] [Indexed: 12/11/2022]
Abstract
The emergence of cancer stem cell theory has profound implications for cancer chemoprevention and therapy. Cancer stem cells give rise to the tumor bulk through continuous self-renewal and differentiation. Understanding the mechanisms that regulate self-renewal is of greatest importance for discovery of anticancer drugs targeting cancer stem cells. Naturally occurring dietary compounds have received increasing attention in cancer chemoprevention. The anticancer effects of many dietary components have been reported for both in vitro and in vivo studies. Recently, a number of studies have found that several dietary compounds can directly or indirectly affect cancer stem cell self-renewal pathways. Herein we review the current knowledge of most common natural dietary compounds for their impact on self-renewal pathways and potential effect against cancer stem cells. Three pathways (Wnt/β-catenin, Hedgehog and Notch) are summarized for their functions in self-renewal of cancer stem cells. The dietary compounds, including curcumin, sulforaphane, soy isoflavone, epigallocatechin-3-gallate, resveratrol, lycopene, piperine and vitamin D(3), are discussed for their direct or indirect effect on these self-renewal pathways. Curcumin and piperine have been demonstrated to target breast cancer stem cells. Sulforaphane has been reported to inhibit pancreatic tumor-initiating cells and breast cancer stem cells. These studies provide a basis for preclinical and clinical evaluation of dietary compounds for chemoprevention of cancer stem cells. This may enable us to discover more preventive strategies for cancer management by reducing cancer resistance and recurrence and improving patient survival.
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Affiliation(s)
- Yanyan Li
- Department of Pharmaceutical Sciences, University of Michigan, Ann Arbor, MI 48109, USA
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EGCG, green tea polyphenols and their synthetic analogs and prodrugs for human cancer prevention and treatment. Adv Clin Chem 2011; 53:155-77. [PMID: 21404918 DOI: 10.1016/b978-0-12-385855-9.00007-2] [Citation(s) in RCA: 149] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cancer-preventive effects of tea polyphenols, especially epigallocatechin-3-gallate (EGCG), have been demonstrated by epidemiological, preclinical, and clinical studies. Green tea polyphenols such as EGCG have the potential to affect multiple biological pathways, including gene expression, growth factor-mediated pathways, the mitogen-activated protein kinase-dependent pathway, and the ubiquitin/proteasome degradation pathway. Therefore, identification of the molecular targets of EGCG should greatly facilitate a better understanding of the mechanisms underlying its anticancer and cancer-preventive activities. Performing structure-activity relationship (SAR) studies could also greatly enhance the discovery of novel tea polyphenol analogs as potential anticancer and cancer-preventive agents. In this chapter, we review the relevant literature as it relates to the effects of natural and synthetic green tea polyphenols and EGCG analogs on human cancer cells and their potential molecular targets as well as their antitumor effects. We also discuss the implications of green tea polyphenols in cancer prevention.
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Landis-Piwowar K, Chen D, Chan TH, Dou QP. Inhibition of catechol-Omicron-methyltransferase activity in human breast cancer cells enhances the biological effect of the green tea polyphenol (-)-EGCG. Oncol Rep 2010; 24:563-9. [PMID: 20596647 DOI: 10.3892/or_00000893] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Tea is one of the most popular beverages in the world and has been studied extensively as a health-promoting beverage that may act to prevent a number of chronic diseases and cancers. (-)-Epigallocatechin gallate [(-)-EGCG], a major component in green tea, is unstable under physiological conditions and methylation of (-)-EGCG by catechol-Omicron-methyltransferase (COMT) is a modification that reduces the biological activity of (-)-EGCG. In the current study, we hypothesized that suppression of COMT activity in human breast cancer cells could increase the proteasome-inhibitory potency of (-)-EGCG and therefore enhance its tumor cell growth-inhibitory activity. We first determined the COMT genotype and basal levels of COMT activity in various human breast cancer cell lines. Furthermore, when breast cancer MDA-MB-231 cells containing high COMT activity were tested, the diminished COMT activity apparently increased the effectiveness of (-)-EGCG via augmented proteasome inhibition and apoptosis induction. This study supplements the previous findings that methylated (-)-EGCG is less bioactive and supports the notion that COMT inhibition may increase the anti-cancer properties of tea polyphenols and the combination may serve as a novel approach or supplemental treatment for breast cancer chemotherapy.
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Affiliation(s)
- Kristin Landis-Piwowar
- Department of Pathology, Barbara Ann Karmanos Cancer Institute, School of Medicine, Wayne State University, Detroit, MI 48201, USA
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Kanwar J, Mohammad I, Yang H, Huo C, Chan TH, Dou QP. Computational modeling of the potential interactions of the proteasome beta5 subunit and catechol-O-methyltransferase-resistant EGCG analogs. Int J Mol Med 2010; 26:209-15. [PMID: 20596600 PMCID: PMC3304469 DOI: 10.3892/ijmm_00000454] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
(-)-Epigallocatechin gallate [(-)-EGCG] has been implicated in cancer chemoprevention and has been shown as an inhibitor of tumor proteasomal chymotrypsin-like activity in vitro and in vivo. However, EGCG is subjected to rapid biotransforming modifications such as methylation by catechol-Omicron-methyltransferase (COMT) that limits its action. We recently reported that structure 7, an EGCG analog which should be resistant to COMT-mediated methylation and inactivation in cells, was able to inhibit the activity of purified 20S proteasome and cellular 26S proteasome. However, the involved molecular mechanism is unknown. Herein, we applied computational solution to understand the possible interaction between EGCG analogs including structure 7 and the proteasome beta5 subunit which is responsible for the chymotrypsin-like activity. We report that the ester carbonyls at C2 and C3 carbon atoms may be the active sites for nucleophilic attack in structure 7 and 5. Equally spaced carbon atoms in COMT-resistant structure 7 give more stable conformation and lower docked free energy than other EGCG analogs. The absence of a second gallate group in structure 16 and 21 significantly decreases the ability to inhibit the proteasome.
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Affiliation(s)
- Jyoti Kanwar
- The Prevention Program, Barbara Ann Karmanos Cancer Institute and Department of Pathology, School of Medicine, Wayne State University, Detroit, MI 48201, USA
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Mohanpuria P, Kumar V, Yadav SK. Tea caffeine: Metabolism, functions, and reduction strategies. Food Sci Biotechnol 2010. [DOI: 10.1007/s10068-010-0041-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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Evensen NA, Braun PC. The effects of tea polyphenols on Candida albicans: inhibition of biofilm formation and proteasome inactivation. Can J Microbiol 2010; 55:1033-9. [PMID: 19898545 DOI: 10.1139/w09-058] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The adherence of Candida albicans to one another and to various host and biomaterial surfaces is an important prerequisite for the colonization and pathogenesis of this organism. Cells in established biofilms exhibit different phenotypic traits and are inordinately resistant to antimicrobial agents. Recent studies have shown that black and green tea polyphenols exhibit both antimicrobial and strong cancer-preventive properties. Experiments were conducted to determine the effects of these polyphenols on C. albicans. Standard growth curves demonstrated a 40% reduction in the growth rate constant (K) with a 2 mg/mL concentration of Polyphenon 60, a green tea extract containing a mixture of polyphenolic compounds. Cultures treated with 1.0 micromol/L -(-)epigallocatechin-3-gallate (EGCG), the most abundant polyphenol, displayed a 75% reduction of viable cells during biofilm formation. Established biofilms treated with EGCG were also reduced, by 80%, as determined through XTT (2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide) colorimetric assays. Identical concentrations of epigallocatechin and epicatechin-3-gallate demonstrated similar biofilm inhibition. Further investigations regarding the possible mechanism of polyphenol action indicate that in vivo proteasome activity was significantly decreased when catechin-treated yeast cells were incubated with a fluorogenic peptide substrate that measured proteasomal chymotrypsin-like and peptidyl-glutamyl peptide-hydrolyzing activities. Impairment of proteasomal activity by tea polyphenols contributes to cellular metabolic and structural disruptions that expedite the inhibition of biofilm formation and maintenance by C. albicans.
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Ayoub S, Melzig MF. Induction of neutral endopeptidase (NEP) activity of SK-N-SH cells by natural compounds from green tea. J Pharm Pharmacol 2010; 58:495-501. [PMID: 16597367 DOI: 10.1211/jpp.58.4.0009] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Abstract
Deposition of amyloid β-peptide as senile plaques in the brain is one of the neuropathological hallmarks of Alzheimer's disease, which is the most prevalent progressive neurodegenerative disease leading to dementia. Neutral endopeptidase is one of the major β-amyloid-degrading enzymes in the brain. To examine the influence of different polyphenols and other natural products from green tea extract (from Camellia sinensis, Theaceae), we used the neuroblastoma cell line SK-N-SH and studied the changes in the specific cellular neutral endopeptidase activity after long-term treatment with these substances. We have shown that caffeine leads to an increase in specific cellular neutral endopeptidase activity more than theophylline, theobromine or theanine. We have also shown that the combination of epicatechin, epigallocatechin and epigallocatechingallate with caffeine, theobromine or theophylline induced cellular neutral endopeptidase activity. It is suggested that the enhancement of cellular neutral endopeptidase activity by green tea extract and its natural products might be correlated with an elevated level of intracellular cyclic adenosine monophosphate.
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Affiliation(s)
- Shereen Ayoub
- Institut für Pharmazie, Freie Universität Berlin, Königin-Luise-Str. 2-4, 14195 Berlin, Germany
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Yang H, Sun DK, Chen D, Cui QC, Gu YY, Jiang T, Chen W, Wan SB, Dou QP. Antitumor activity of novel fluoro-substituted (-)-epigallocatechin-3-gallate analogs. Cancer Lett 2009; 292:48-53. [PMID: 19962231 DOI: 10.1016/j.canlet.2009.11.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2009] [Revised: 10/26/2009] [Accepted: 11/05/2009] [Indexed: 02/08/2023]
Abstract
Epidemiological studies support the cancer-preventive effects of green tea and its main constituent (-)-epigallocatechin gallate [(-)-EGCG], however, (-)-EGCG is unstable under physiological conditions. Here we report that two novel fluoro-substituted (-)-EGCG analogs inhibited tumor growth with similar potency to that of Pro-EGCG (1) which has improved potency over parental compound (-)-EGCG in human breast cancer MDA-MB-231 xenografts. MDA-MB-231 tumors treated with each fluoro-substituted (-)-EGCG analog showed proteasome inhibition and apoptotic cell death, suggesting that the proteasome might be one of the cellular targets of fluoro-(-)-EGCGs and that proteasome inhibition is partially responsible for the observed antitumor activity.
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Affiliation(s)
- Huanjie Yang
- The Prevention Program, Barbara Ann Karmanos Cancer Institute, and Department of Pathology, School of Medicine, Wayne State University, Detroit, MI, USA
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Li Y, Zhang T, Jiang Y, Lee HF, Schwartz SJ, Sun D. (-)-Epigallocatechin-3-gallate inhibits Hsp90 function by impairing Hsp90 association with cochaperones in pancreatic cancer cell line Mia Paca-2. Mol Pharm 2009; 6:1152-9. [PMID: 19438225 DOI: 10.1021/mp900037p] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
(-)-Epigallocatechin-3-gallate [(-)-EGCG], the most abundant polyphenolic catechin in green tea, showed chemoprevention and anticancer activities. (-)-EGCG was reported to bind to the C-terminal domain of heat shock protein 90 (Hsp90). The purpose of this study is to investigate (-)-EGCG as a novel Hsp90 inhibitor to impair Hsp90 superchaperone complex for simultaneous downregulation of oncogenic proteins in pancreatic cancer cells. MTS assay showed that (-)-EGCG exhibited antiproliferative activity against pancreatic cancer cell line Mia Paca-2 in vitro with IC50 below 50 muM. (-)-EGCG increased caspase-3 activity up to 3-fold in a time- and concentration-dependent manner. Western blotting analysis demonstrated that (-)-EGCG induced downregulation of oncogenic Hsp90 client proteins by approximately 70-95%, including Akt, Cdk4, Raf-1, Her-2, and pERK. Co-immunoprecipitation showed that (-)-EGCG decreased the association of cochaperones p23 and Hsc70 with Hsp90 by more than 50%, while it had little effect on the ATP binding to Hsp90. Proteolytic fingerprinting assay confirmed direct binding between (-)-EGCG and the Hsp90 C-terminal domain. These data suggest that the binding of (-)-EGCG to Hsp90 impairs the association of Hsp90 with its cochaperones, thereby inducing degradation of Hsp90 client proteins, resulting antiproliferating effects in pancreatic cancer cells.
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Affiliation(s)
- Yanyan Li
- Department of Food Science and Technology, The Ohio State University, Columbus, Ohio 43210, USA
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Boehm K, Borrelli F, Ernst E, Habacher G, Hung SK, Milazzo S, Horneber M. Green tea (Camellia sinensis) for the prevention of cancer. THE COCHRANE DATABASE OF SYSTEMATIC REVIEWS 2009. [PMID: 19588362 DOI: 10.1002/14651858.cd005004.pub2.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Tea is one of the most commonly consumed beverages worldwide. Teas from the plant Camellia sinensis can be grouped into green, black and oolong tea. Cross-culturally tea drinking habits vary. Camellia sinensis contains the active ingredient polyphenol, which has a subgroup known as catechins. Catechins are powerful antioxidants. It has been suggested that green tea polyphenol may inhibit cell proliferation and observational studies have suggested that green tea may have cancer-preventative effects. OBJECTIVES To critically assess any associations between green tea consumption and the risk of cancer incidence and mortality. SEARCH STRATEGY We searched eligible studies up to January 2009 in the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Amed, CancerLit, Psych INFO and Phytobase and reference lists of previous reviews and included studies. SELECTION CRITERIA We included all prospective, controlled interventional studies and observational studies, which either assessed the associations between green tea consumption and risk of cancer incidence or that reported on cancer mortality. DATA COLLECTION AND ANALYSIS At least two review authors independently applied the study criteria, extracted data and assessed methodological quality of studies. Due to the nature of included studies, which were mainly epidemiological, results were summarised descriptively according to cancer diagnosis. MAIN RESULTS Fifty-one studies with more than 1.6 million participants were included. Twenty-seven of them were case-control studies, 23 cohort studies and one randomised controlled trial (RCT).Twenty-seven studies tried to establish an association between green tea consumption and cancer of the digestive tract, mainly of the upper gastrointestinal tract, five with breast cancer, five with prostate cancer, three with lung cancer, two with ovarian cancer, two with urinary bladder cancer one with oral cancer, three further studies included patients with various cancer diagnoses.The methodological quality was measured with the Newcastle-Ottawa scale (NOS). The 9 nested case-control studies within prospective cohorts were of high methodological quality, 13 of medium, and 1 of low. One retrospective case-control study was of high methodological quality and 21 of medium and 5 of low.Results from studies assessing associations between green tea and risk of digestive tract cancer incidence were highly contradictory. There was limited evidence that green tea could reduce the incidence of liver cancer. The evidence for esophageal, gastric, colon, rectum, and pancreatic cancer was conflicting. In prostate cancer, observational studies with higher methodological quality and the only included RCT suggested a decreased risk in men consuming higher quantities green tea or green tea extracts. However, there was limited to moderate evidence that the consumption of green tea reduced the risk of lung cancer, especially in men, and urinary bladder cancer or that it could even increase the risk of the latter. There was moderate to strong evidence that green tea consumption does not decrease the risk of dying from gastric cancer. There was limited moderate to strong evidence for lung, pancreatic and colorectal cancer. AUTHORS' CONCLUSIONS There is insufficient and conflicting evidence to give any firm recommendations regarding green tea consumption for cancer prevention. The results of this review, including its trends of associations, need to be interpreted with caution and their generalisability is questionable, as the majority of included studies were carried out in Asia (n = 47) where the tea drinking culture is pronounced. Desirable green tea intake is 3 to 5 cups per day (up to 1200 ml/day), providing a minimum of 250 mg/day catechins. If not exceeding the daily recommended allowance, those who enjoy a cup of green tea should continue its consumption. Drinking green tea appears to be safe at moderate, regular and habitual use.
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Affiliation(s)
- Katja Boehm
- Medizinische Klinik 5-Schwerpunkt Onkologie / Haematologie, Klinikum Nord, Prof.-Ernst-Nathan-Str. 1, Nuernberg, Germany, D-90419
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Boehm K, Borrelli F, Ernst E, Habacher G, Hung SK, Milazzo S, Horneber M. Green tea (Camellia sinensis) for the prevention of cancer. Cochrane Database Syst Rev 2009; 2009:CD005004. [PMID: 19588362 PMCID: PMC6457677 DOI: 10.1002/14651858.cd005004.pub2] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
BACKGROUND Tea is one of the most commonly consumed beverages worldwide. Teas from the plant Camellia sinensis can be grouped into green, black and oolong tea. Cross-culturally tea drinking habits vary. Camellia sinensis contains the active ingredient polyphenol, which has a subgroup known as catechins. Catechins are powerful antioxidants. It has been suggested that green tea polyphenol may inhibit cell proliferation and observational studies have suggested that green tea may have cancer-preventative effects. OBJECTIVES To critically assess any associations between green tea consumption and the risk of cancer incidence and mortality. SEARCH STRATEGY We searched eligible studies up to January 2009 in the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Amed, CancerLit, Psych INFO and Phytobase and reference lists of previous reviews and included studies. SELECTION CRITERIA We included all prospective, controlled interventional studies and observational studies, which either assessed the associations between green tea consumption and risk of cancer incidence or that reported on cancer mortality. DATA COLLECTION AND ANALYSIS At least two review authors independently applied the study criteria, extracted data and assessed methodological quality of studies. Due to the nature of included studies, which were mainly epidemiological, results were summarised descriptively according to cancer diagnosis. MAIN RESULTS Fifty-one studies with more than 1.6 million participants were included. Twenty-seven of them were case-control studies, 23 cohort studies and one randomised controlled trial (RCT).Twenty-seven studies tried to establish an association between green tea consumption and cancer of the digestive tract, mainly of the upper gastrointestinal tract, five with breast cancer, five with prostate cancer, three with lung cancer, two with ovarian cancer, two with urinary bladder cancer one with oral cancer, three further studies included patients with various cancer diagnoses.The methodological quality was measured with the Newcastle-Ottawa scale (NOS). The 9 nested case-control studies within prospective cohorts were of high methodological quality, 13 of medium, and 1 of low. One retrospective case-control study was of high methodological quality and 21 of medium and 5 of low.Results from studies assessing associations between green tea and risk of digestive tract cancer incidence were highly contradictory. There was limited evidence that green tea could reduce the incidence of liver cancer. The evidence for esophageal, gastric, colon, rectum, and pancreatic cancer was conflicting. In prostate cancer, observational studies with higher methodological quality and the only included RCT suggested a decreased risk in men consuming higher quantities green tea or green tea extracts. However, there was limited to moderate evidence that the consumption of green tea reduced the risk of lung cancer, especially in men, and urinary bladder cancer or that it could even increase the risk of the latter. There was moderate to strong evidence that green tea consumption does not decrease the risk of dying from gastric cancer. There was limited moderate to strong evidence for lung, pancreatic and colorectal cancer. AUTHORS' CONCLUSIONS There is insufficient and conflicting evidence to give any firm recommendations regarding green tea consumption for cancer prevention. The results of this review, including its trends of associations, need to be interpreted with caution and their generalisability is questionable, as the majority of included studies were carried out in Asia (n = 47) where the tea drinking culture is pronounced. Desirable green tea intake is 3 to 5 cups per day (up to 1200 ml/day), providing a minimum of 250 mg/day catechins. If not exceeding the daily recommended allowance, those who enjoy a cup of green tea should continue its consumption. Drinking green tea appears to be safe at moderate, regular and habitual use.
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Affiliation(s)
- Katja Boehm
- Klinikum NordMedizinische Klinik 5‐Schwerpunkt Onkologie/HaematologieProf.‐Ernst‐Nathan‐Str. 1NuernbergGermanyD‐90419
| | - Francesca Borrelli
- University of Naples 'Federico II'Department of Experimental PharmacologyVia D Montesano 49NaplesItaly80131
| | - Edzard Ernst
- Peninsula Medical School, University of ExeterComplementary Medicine DepartmentExeterUK
| | - Gabi Habacher
- Small Animal HospitalFeline CentreDepartment of Veterinary Clinical SciencesUniversity of BristolLangfordUK
| | - Shao Kang Hung
- Peninsula Medical School, Universities of Exeter and PlymouthComplementary Medicine25 Victoria Park RoadExeterUKEX2 4NT
| | - Stefania Milazzo
- Paracelsus Medical University, Klinikum NuernbergDepartment of Internal Medicine, Division of Oncology and HematologyProf.‐Ernst‐Nathan‐Str. 1NuernbergGermanyD‐90419
| | - Markus Horneber
- Paracelsus Medical University, Klinikum NurembergDepartment of Internal Medicine, Division of Oncology and HematologyProf.‐Ernst‐Nathan‐Str. 1NurembergGermanyD‐90419
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Tang Y, Simoneau AR, Xie J, Shahandeh B, Zi X. Effects of the kava chalcone flavokawain A differ in bladder cancer cells with wild-type versus mutant p53. Cancer Prev Res (Phila) 2009; 1:439-51. [PMID: 19138991 DOI: 10.1158/1940-6207.capr-08-0165] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Flavokawain A is the predominant chalcone from kava extract. We have assessed the mechanisms of flavokawain A's action on cell cycle regulation. In a p53 wild-type, low-grade, and papillary bladder cancer cell line (RT4), flavokawain A increased p21/WAF1 and p27/KIP1, which resulted in a decrease in cyclin-dependent kinase-2 (CDK2) kinase activity and subsequent G(1) arrest. The increase of p21/WAF1 protein corresponded to an increased mRNA level, whereas p27/KIP1 accumulation was associated with the down-regulation of SKP2, which then increased the stability of the p27/KIP1 protein. The accumulation of p21/WAF1 and p27/KIP1 was independent of cell cycle position and thus not a result of the cell cycle arrest. In contrast, flavokawain A induced a G(2)-M arrest in six p53 mutant-type, high-grade bladder cancer cell lines (T24, UMUC3, TCCSUP, 5637, HT1376, and HT1197). Flavokawain A significantly reduced the expression of CDK1-inhibitory kinases, Myt1 and Wee1, and caused cyclin B1 protein accumulation leading to CDK1 activation in T24 cells. Suppression of p53 expression by small interfering RNA in RT4 cells restored Cdc25C expression and down-regulated p21/WAF1 expression, which allowed Cdc25C and CDK1 activation, which then led to a G(2)-M arrest and an enhanced growth-inhibitory effect by flavokawain A. Consistently, flavokawain A also caused a pronounced CDK1 activation and G(2)-M arrest in p53 knockout but not in p53 wild-type HCT116 cells. This selectivity of flavokawain A for inducing a G(2)-M arrest in p53-defective cells deserves further investigation as a new mechanism for the prevention and treatment of bladder cancer.
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Affiliation(s)
- Yaxiong Tang
- 1Department of Urology, University of California, Irvine, Orange, California 92868, USA
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39
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Labbé D, Têtu B, Trudel D, Bazinet L. Catechin stability of EGC- and EGCG-enriched tea drinks produced by a two-step extraction procedure. Food Chem 2008. [DOI: 10.1016/j.foodchem.2008.03.048] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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40
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Dou QP, Landis-Piwowar KR, Chen D, Huo C, Wan SB, Chan TH. Green tea polyphenols as a natural tumour cell proteasome inhibitor. Inflammopharmacology 2008; 16:208-12. [PMID: 18815743 PMCID: PMC3303149 DOI: 10.1007/s10787-008-8017-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The cancer-preventive effects of green tea and its main constituent (-)-epigallocatechin gallate [(-)-EGCG] are widely supported by results from epidemiological, cell culture, animal and clinical studies although the molecular target has not been well defined. We previously reported that ester bond-containing tea polyphenols, e. g. (-)-EGCG, and their synthetic analogs potently and specifically inhibited the proteasomal activity. Subsequently, we further demonstrated that methylation on green tea polyphenols under physiological conditions decreased their proteasome-inhibitory activity, contributing to decreased cancer-preventive effects of tea consumption. Since (-)-EGCG is unstable under physiological conditions, we also developed the peracetate-protected or prodrug form of (-)-EGCG, Pro-EGCG (1), and shown that Pro-EGCG (1) increases the bioavailability, stability, and proteasome-inhibitory and anticancer activities of (-)-EGCG in human breast cancer cells and xenografts, suggesting its potential use for cancer prevention and treatment.
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Affiliation(s)
- Q P Dou
- The Prevention Program, Barbara Ann Karmanos Cancer Institute and Department of Pathology, School of Medicine, Wayne State University, 540.1 HWCRC, 4100 John R Rd, Detroit, Michigan 48201, USA.
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Yu Z, Qin XL, Gu YY, Chen D, Cui QC, Jiang T, Wan SB, Dou QP. Prodrugs of fluoro-substituted benzoates of EGC as tumor cellular proteasome inhibitors and apoptosis inducers. Int J Mol Sci 2008; 9:951-961. [PMID: 19325839 PMCID: PMC2658777 DOI: 10.3390/ijms9060951] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2008] [Revised: 05/12/2008] [Accepted: 05/26/2008] [Indexed: 12/03/2022] Open
Abstract
The most potent catechin in green tea is (-)-epigallocatechin-3-gallate [(-)-EGCG], which, however, is unstable under physiological conditions. To discover more stable and more potent polyphenol proteasome inhibitors, we synthesized several novel fluoro-substituted (-)-EGCG analogs, named F-EGCG analogs, as well as their prodrug forms with all of -OH groups protected by acetate. We report that the prodrug form of one F-EGCG analog exhibited greater potency than the previously reported peracetate of (-)-EGCG to inhibit proteasomal activity, suppress cell proliferation, and induce apoptosis in human leukemia Jurkat T cells, demonstrating the potential of these compounds to be developed into novel anti-cancer and cancer-preventive agents.
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Affiliation(s)
- Zhiyong Yu
- The Prevention Program, Barbara Ann Karmanos Cancer Institute, and Department of Pathology, School of Medicine, Wayne State University, Detroit, Michigan, USA
- Shandong Tumor Hospital & Institute, Breast Cancer Center, Jinan, Shandong, China
| | - Xu Long Qin
- The Prevention Program, Barbara Ann Karmanos Cancer Institute, and Department of Pathology, School of Medicine, Wayne State University, Detroit, Michigan, USA
| | - Yan Yan Gu
- Key Laboratory of Marine Drug, Ministry of Education, Medical College, Ocean University of China, Qingdao, China
| | - Di Chen
- The Prevention Program, Barbara Ann Karmanos Cancer Institute, and Department of Pathology, School of Medicine, Wayne State University, Detroit, Michigan, USA
| | - Qiuzhi Cindy Cui
- The Prevention Program, Barbara Ann Karmanos Cancer Institute, and Department of Pathology, School of Medicine, Wayne State University, Detroit, Michigan, USA
| | - Tao Jiang
- Key Laboratory of Marine Drug, Ministry of Education, Medical College, Ocean University of China, Qingdao, China
| | - Sheng Biao Wan
- Key Laboratory of Marine Drug, Ministry of Education, Medical College, Ocean University of China, Qingdao, China
| | - Q. Ping Dou
- The Prevention Program, Barbara Ann Karmanos Cancer Institute, and Department of Pathology, School of Medicine, Wayne State University, Detroit, Michigan, USA
- Author to whom correspondence should be addressed; E-Mail:
; Tel. +313-576-8301
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Multitargeted therapy of cancer by green tea polyphenols. Cancer Lett 2008; 269:269-80. [PMID: 18501505 DOI: 10.1016/j.canlet.2008.04.014] [Citation(s) in RCA: 240] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2008] [Revised: 02/20/2008] [Accepted: 04/09/2008] [Indexed: 12/11/2022]
Abstract
Tea ranks second only to water as a major component of fluid intake worldwide and has been considered a health-promoting beverage since ancient times. For the past two decades, we and others have been investigating the potential cancer preventive and therapeutic effects of green tea and its polyphenolic mixture termed GTP. It has become clear that much of these effects of GTP are mediated by its most abundant catechin, epigallocatechin gallate (EGCG). Large amount of encouraging data from in vitro and animal models has emerged making clear that green tea is a nature's gift molecule endowed with anticancer effects. Epidemiological and geographical observations suggest that these laboratory data may be applicable to human population. Clinical trials of GTP, especially in prostate cancer patients have yielded encouraging results. This article briefly reviews properties of GTP, especially EGCG with reference to multitargeted therapy of cancer.
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Nakagawa T, Nakatsuka A, Yano K, Yasugahira S, Nakamura R, Sun N, Itai A, Suzuki T, Itamura H. Expressed sequence tags from persimmon at different developmental stages. PLANT CELL REPORTS 2008; 27:931-938. [PMID: 18301901 DOI: 10.1007/s00299-008-0518-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2007] [Revised: 01/28/2008] [Accepted: 02/10/2008] [Indexed: 05/26/2023]
Abstract
Persimmon (Diospyros kaki Thunb.) is an important fruit in Asian countries, where it is eaten as a fresh fruit and is also used for many other purposes. To understand the molecular mechanism of fruit development and ripening in persimmon, we generated a total of 9,952 expressed sequence tags (ESTs) from randomly selected clones of two different cDNA libraries. One cDNA library was derived from fruit of "Saijo" persimmon at an early stage of development, and the other from ripening fruit. These ESTs were clustered into 6,700 non-redundant sequences. Of the 6,700 non-redundant sequences evaluated, the deduced amino acid sequences of 4,356 (65%) showed significant homology to known proteins, and 2,344 (35%) showed no significant similarity to any known proteins in Arabidopsis databases. We report comparison of genes identified in the two cDNA libraries and describe some putative genes involved in proanthocyanidin and carotenoid synthesis. This study provides the first global overview of a set of genes that are expressed during fruit development and ripening in persimmon.
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Affiliation(s)
- T Nakagawa
- Department of Molecular and Functional Genomics, Center for Integrated Research in Science, Shimane University, Matsue 690-8504, Japan
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Chen D, Milacic V, Chen MS, Wan SB, Lam WH, Huo C, Landis-Piwowar KR, Cui QC, Wali A, Chan TH, Dou QP. Tea polyphenols, their biological effects and potential molecular targets. Histol Histopathol 2008; 23:487-96. [PMID: 18228206 DOI: 10.14670/hh-23.487] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Tea is the most popular beverage in the world, second only to water. Tea contains an infusion of the leaves from the Camellia sinensis plant rich in polyphenolic compounds known as catechins, the most abundant of which is (-)-EGCG. Although tea has been consumed for centuries, it has only recently been studied extensively as a health-promoting beverage that may act to prevent a number of chronic diseases and cancers. The results of several investigations indicate that green tea consumption may be of modest benefit in reducing the plasma concentration of cholesterol and preventing atherosclerosis. Additionally, the cancer-preventive effects of green tea are widely supported by results from epidemiological, cell culture, animal and clinical studies. In vitro cell culture studies show that tea polyphenols potently induce apoptotic cell death and cell cycle arrest in tumor cells but not in their normal cell counterparts. Green tea polyphenols were shown to affect several biological pathways, including growth factor-mediated pathway, the mitogen-activated protein (MAP) kinase-dependent pathway, and ubiquitin/proteasome degradation pathways. Various animal studies have revealed that treatment with green tea inhibits tumor incidence and multiplicity in different organ sites such as skin, lung, liver, stomach, mammary gland and colon. Recently, phase I and II clinical trials have been conducted to explore the anticancer effects of green tea in humans. A major challenge of cancer prevention is to integrate new molecular findings into clinical practice. Therefore, identification of more molecular targets and biomarkers for tea polyphenols is essential for improving the design of green tea trials and will greatly assist in a better understanding of the mechanisms underlying its anti-cancer activity.
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Affiliation(s)
- D Chen
- The Prevention Program, Barbara Ann Karmanos Cancer Institute and Department of Pathology, School of Medicine, Wayne State University, Detroit, Michigan 48201, USA
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Kuzuhara T, Suganuma M, Fujiki H. Green tea catechin as a chemical chaperone in cancer prevention. Cancer Lett 2008; 261:12-20. [PMID: 18068893 DOI: 10.1016/j.canlet.2007.10.037] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2007] [Accepted: 10/30/2007] [Indexed: 11/18/2022]
Abstract
Green tea catechins have recently gained significant acceptance as a cancer preventive, and one of the important features of catechins is their interactions with various target molecules. We recently found a functional and structural similarity between catechins and chaperones: Stochastic conformational analysis in silico revealed numerous conformations of (-)-epigallocatechin gallate, (-)-epicatechin gallate and (-)-epigallocatechin, showing a unique flexibility and mobility of the catechin molecules and suggesting the significance of a galloyl group in conformational variation. Since these conformations result in interaction with various types of molecules, we think that green tea catechin induces cancer preventive activity mediated through a chaperone-like property.
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Affiliation(s)
- Takashi Kuzuhara
- Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Tokushima 770-8514, Japan.
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Na HK, Surh YJ. Modulation of Nrf2-mediated antioxidant and detoxifying enzyme induction by the green tea polyphenol EGCG. Food Chem Toxicol 2008; 46:1271-8. [DOI: 10.1016/j.fct.2007.10.006] [Citation(s) in RCA: 315] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2007] [Revised: 09/26/2007] [Accepted: 10/03/2007] [Indexed: 10/22/2022]
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Melanoma vasculogenic mimicry is strongly related to reactive oxygen species level. Melanoma Res 2008; 17:370-9. [PMID: 17992120 DOI: 10.1097/cmr.0b013e3282f1d2ec] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The concept of 'vasculogenic mimicry' (VM) was introduced to describe the unique ability of highly invasive tumor cells to form capillary-like structures (CLS) and matrix-rich patterned network in three-dimensional culture that mimic embryonic vasculogenic network. Recently, we have shown that CLS formation requires apoptotic cell death through activation of caspase-3-dependent mechanism. In this study, to identify some molecular determinants driving aggressive melanoma cells to express a latent 'angiogenic program' that recapitulates the early events of CLS formation, we focused on the involvement of antioxidants (AOs) in the process of melanoma VM. We have studied the effects of resveratrol, (-)-epigallocathechin gallate, N-acetyl-cysteine (NAC) and Trolox on the ability of melanoma cells to form/destroy CLS. We observed that the formation of CLS was strongly related to reactive oxygen species level. In vivo animal experiments confirmed the involvement of reactive oxygen species level in melanoma VM. To understand the molecular mechanisms of this phenomenon, we specifically looked for induction of apoptosis and vascular endothelial growth factor (VEGF) release. Western blot analysis revealed that the level of VEGF, VEGF receptors (VEGF-Rs) and active caspase-3 dramatically decreased in cells treated with AOs. Here, we also report further experiments designed to determine whether the crosstalk between AOs and apoptosis exists in melanoma VM.
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Kuzuhara T, Tanabe A, Sei Y, Yamaguchi K, Suganuma M, Fujiki H. Synergistic effects of multiple treatments, and both DNA and RNA direct bindings on, green tea catechins. Mol Carcinog 2007; 46:640-5. [PMID: 17440927 DOI: 10.1002/mc.20332] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
This article reviews two main topics: (1) the synergistic effects of multiple treatments with green tea catechin and (2) the direct binding of (-)-epigallocatechin gallate (EGCG) to both DNA and RNA molecules. Japanese drink green tea throughout the day, so we studied whether multiple treatments of cells with EGCG would enhance the expression of apoptosis-related genes, such as growth arrest and DNA damage-inducible gene (GADD153) and cyclin-dependent kinase inhibitor gene (p21(waf1)): The results suggest that the synergistic enhancement of both GADD153 and p21(waf1) gene expressions by multiple treatments plays a significant role in human cancer prevention with green tea beverage. Our previous observation-that nucleic acids extracted from catechin-treated cells are colored-allowed us to speculate that catechins directly interact with nucleic acids. Surface plasmon resonance assay (Biacore) indicated that four catechins, EGCG, (-)-epicatechin gallate (ECG), (+)-gallocatechin gallate (GCG), and (+)-catechin gallate (CG), bound to DNA oligomers. Cold spray ionization mass spectrometry (CSI-MS) analysis showed that one to three EGCG molecules bound to single-stranded 18 mers of DNA and RNA. Moreover, one or two molecules of EGCG bound to double-stranded AG:CT oligomers of various nucleotide lengths. Double-stranded DNA (dsDNA) oligomers were detected only as EGCG-bound forms at high temperature, whereas at low temperature both the free and bound forms were detected, suggesting that EGCG protects double-stranded DNA oligomers from double-stranded melting into single-stranded DNA. We assume that catechins accumulate in both double-stranded DNA and RNA molecules through multiple administrations of green tea beverage in in vivo, and that the accumulated green tea catechins play a significant role for human cancer prevention.
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Affiliation(s)
- Takashi Kuzuhara
- Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Tokushima, Japan
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Osanai K, Landis-Piwowar KR, Dou QP, Chan TH. A para-amino substituent on the D-ring of green tea polyphenol epigallocatechin-3-gallate as a novel proteasome inhibitor and cancer cell apoptosis inducer. Bioorg Med Chem 2007; 15:5076-82. [PMID: 17544279 PMCID: PMC2963865 DOI: 10.1016/j.bmc.2007.05.041] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2007] [Revised: 05/12/2007] [Accepted: 05/15/2007] [Indexed: 11/24/2022]
Abstract
Analogs of (-)-EGCG containing a para-amino group on the D-ring in place of the hydroxyl groups have been synthesized and their proteasome inhibitory activities were studied. We found that, the O-acetylated (-)-EGCG analogs possessing a p-NH(2) or p-NHBoc (Boc; tert-butoxycarbonyl) D-ring (5 and 7) act as novel tumor cellular proteasome inhibitors and apoptosis inducers with potency similar to natural (-)-EGCG and similar to (-)-EGCG peracetate. These data suggest that the acetylated amino-GTP analogs have the potential to be developed into novel anticancer agents.
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Affiliation(s)
- Kumi Osanai
- Department of Applied Biology and Chemical Technology and the Open Laboratory of Chirotechnology, Institute of Molecular Technology for Drug Discovery and Synthesis, The Hong Kong Polytechnic University, Hung Hom, Hong Kong, SAR, China
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A Double-Blind, Randomized-Controlled Trial of a Nutritional Supplement (abs+) Containing Conjugated Linoleic Acid (CLA) and Epigallocatechin-Gallate (EGCG) in Human Weight Loss. ACTA ACUST UNITED AC 2007. [DOI: 10.1300/j044v12n03_05] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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