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Li XX, Liu C, Dong SL, Ou CS, Lu JL, Ye JH, Liang YR, Zheng XQ. Anticarcinogenic potentials of tea catechins. Front Nutr 2022; 9:1060783. [PMID: 36545470 PMCID: PMC9760998 DOI: 10.3389/fnut.2022.1060783] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 11/21/2022] [Indexed: 12/07/2022] Open
Abstract
Catechins are a cluster of polyphenolic bioactive components in green tea. Anticarcinogenic effects of tea catechins have been reported since the 1980s, but it has been controversial. The present paper reviews the advances in studies on the anticarcinogenic activities of tea and catechins, including epidemiological evidence and anticarcinogenic mechanism. Tea catechins showed antagonistic effects on many cancers, such as gynecological cancers, digestive tract cancers, incident glioma, liver and gallbladder cancers, lung cancer, etc. The mechanism underlying the anticarcinogenic effects of catechins involves in inhibiting the proliferation and growth of cancer cells, scavenging free radicals, suppressing metastasis of cancer cells, improving immunity, interacting with other anticancer drugs, and regulating signaling pathways. The inconsistent results and their causes are also discussed in this paper.
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Affiliation(s)
- Xiao-Xiang Li
- Tea Research Institute, Zhejiang University, Hangzhou, China
| | - Chang Liu
- Tea Science Society of China, Hangzhou, China
| | - Shu-Ling Dong
- Tea Research Institute, Zhejiang University, Hangzhou, China
| | - Can-Song Ou
- Development Center of Liubao Tea Industry, Cangwu, China
| | - Jian-Liang Lu
- Tea Research Institute, Zhejiang University, Hangzhou, China
| | - Jian-Hui Ye
- Tea Research Institute, Zhejiang University, Hangzhou, China
| | - Yue-Rong Liang
- Tea Research Institute, Zhejiang University, Hangzhou, China,*Correspondence: Yue-Rong Liang,
| | - Xin-Qiang Zheng
- Tea Research Institute, Zhejiang University, Hangzhou, China,Xin-Qiang Zheng,
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2
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Wang S, Li X, Yang Y, Xie J, Liu M, Zhang Y, Zhang Y, Zhao Q. Does coffee, tea and caffeine consumption reduce the risk of incident breast cancer? A systematic review and network meta-analysis. Public Health Nutr 2021; 24:6377-6389. [PMID: 34311801 DOI: 10.1017/s1368980021000720] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
OBJECTIVE We aimed to evaluate the association between coffee and/or tea consumption and breast cancer (BC) risk among premenopausal and postmenopausal women and to conduct a network meta-analysis. DESIGN Systematic review and network meta-analysis. SETTING We conducted a systematic review of electronic publications in the last 30 years to identify case-control studies or prospective cohort studies that evaluated the effects of coffee and tea intake. RESULTS Forty-five studies that included more than 3 323 288 participants were eligible for analysis. Network meta-analysis was performed to determine the effects of coffee and/or tea consumption on reducing BC risk in a dose-dependent manner and differences in coffee/tea type, menopause status, hormone receptor and the BMI in subgroup and meta-regression analyses. According to the first pairwise meta-analysis, low-dose coffee intake and high-dose tea intake may exhibit efficacy in preventing ER(estrogen receptor)- BC, particularly in postmenopausal women. Then, we performed another pairwise and network meta-analysis and determined that the recommended daily doses were 2-3 cups/d of coffee or ≥5 cups/d of tea, which contained a high concentration of caffeine, particularly in postmenopausal women. CONCLUSIONS Coffee and tea consumption is not associated with a reduction in the overall BC risk in postmenopausal women and is associated with a potentially lower risk of ER- BC. And the highest recommended dose is 2-3 cups of coffee/d or ≥5 cups of tea/d. They are potentially useful dietary protectants for preventing BC.
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Affiliation(s)
- Shu Wang
- Department of Clinical Pharmacy, Shenyang Pharmaceutical University, No. 103 Wenhua Road, Shenyang110016, People's Republic of China
| | - Xiang Li
- Department of Clinical Pharmacy, Shenyang Pharmaceutical University, No. 103 Wenhua Road, Shenyang110016, People's Republic of China
| | - Yue Yang
- Department of Clinical Pharmacy, Shenyang Pharmaceutical University, No. 103 Wenhua Road, Shenyang110016, People's Republic of China
| | - Jingping Xie
- Office of Retirement, Affiliated Hospital of Liaoning University of Traditional Chinese Medicine, Shenyang, People's Republic of China
| | - Mingyue Liu
- Department of Clinical Pharmacy, Shenyang Pharmaceutical University, No. 103 Wenhua Road, Shenyang110016, People's Republic of China
| | - Ya Zhang
- College of Pharmacy, Shenyang Pharmaceutical University, Shenyang, People's Republic of China
| | - Yingshi Zhang
- Department of Clinical Pharmacy, Shenyang Pharmaceutical University, No. 103 Wenhua Road, Shenyang110016, People's Republic of China
| | - Qingchun Zhao
- Department of Clinical Pharmacy, Shenyang Pharmaceutical University, No. 103 Wenhua Road, Shenyang110016, People's Republic of China
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3
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Sindhu RK, Verma R, Salgotra T, Rahman MH, Shah M, Akter R, Murad W, Mubin S, Bibi P, Qusti S, Alshammari EM, Batiha GES, Tomczyk M, Al-kuraishy HM. Impacting the Remedial Potential of Nano Delivery-Based Flavonoids for Breast Cancer Treatment. Molecules 2021; 26:5163. [PMID: 34500597 PMCID: PMC8434139 DOI: 10.3390/molecules26175163] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/06/2021] [Accepted: 08/21/2021] [Indexed: 11/23/2022] Open
Abstract
Breast cancer persists as a diffuse source of cancer despite persistent detection and treatment. Flavonoids, a type of polyphenol, appear to be a productive option in the treatment of breast cancer, because of their capacity to regulate the tumor related functions of class of compounds. Plant polyphenols are flavonoids that appear to exhibit properties which are beneficial for breast cancer therapy. Numerous epidemiologic studies have been performed on the dynamic effect of plant polyphenols in the prevention of breast cancer. There are also subclasses of flavonoids that have antioxidant and anticarcinogenic activity. These can regulate the scavenging activity of reactive oxygen species (ROS) which help in cell cycle arrest and suppress the uncontrolled division of cancer cells. Numerous studies have also been performed at the population level, one of which reported a connection between cancer risk and intake of dietary flavonoids. Breast cancer appears to show intertumoral heterogeneity with estrogen receptor positive and negative cells. This review describes breast cancer, its various factors, and the function of flavonoids in the prevention and treatment of breast cancer, namely, how flavonoids and their subtypes are used in treatment. This review proposes that cancer risk can be reduced, and that cancer can be even cured by improving dietary intake. A large number of studies also suggested that the intake of fruit and vegetables is associated with reduced breast cancer and paper also includes the role and the use of nanodelivery of flavonoids in the healing of breast cancer. In addition, the therapeutic potential of orally administered phyto-bioactive compounds (PBCs) is narrowed because of poor stability and oral bioavailability of compounds in the gastrointestinal tract (GIT), and solubility also affects bioavailability. In recent years, creative nanotechnology-based approaches have been advised to enhance the activity of PBCs. Nanotechnology also offers the potential to become aware of disease at earlier stages, such as the detection of hidden or unconcealed metastasis colonies in patients diagnosed with lung, colon, prostate, ovarian, and breast cancer. However, nanoformulation-related effects and safety must not be overlooked. This review gives a brief discussion of nanoformulations and the effect of nanotechnology on herbal drugs.
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Affiliation(s)
- Rakesh K. Sindhu
- Chitkara College of Pharmacy, Chitkara University, Punjab 140401, India; (R.V.); (T.S.)
| | - Rishu Verma
- Chitkara College of Pharmacy, Chitkara University, Punjab 140401, India; (R.V.); (T.S.)
| | - Twinkle Salgotra
- Chitkara College of Pharmacy, Chitkara University, Punjab 140401, India; (R.V.); (T.S.)
| | - Md. Habibur Rahman
- Department of Pharmacy, Southeast University, Banani, Dhaka 1213, Bangladesh
- Department of Global Medical Science, Wonju College of Medicine, Yonsei University, Gangwon, Wonju 26426, Korea;
| | - Muddaser Shah
- Department of Botany, Abdul Wali Khan University Mardan, Mardan 23200, Pakistan; (W.M.); (P.B.)
| | - Rokeya Akter
- Department of Global Medical Science, Wonju College of Medicine, Yonsei University, Gangwon, Wonju 26426, Korea;
| | - Waheed Murad
- Department of Botany, Abdul Wali Khan University Mardan, Mardan 23200, Pakistan; (W.M.); (P.B.)
| | - Sidra Mubin
- Department of Botany, Hazara University Mansehra, Mansehra 21310, Pakistan;
| | - Parveen Bibi
- Department of Botany, Abdul Wali Khan University Mardan, Mardan 23200, Pakistan; (W.M.); (P.B.)
| | - Safaa Qusti
- Biochemistry Department, Faculty of Science, King Abdul Aziz University, Jeddah 22230, Saudi Arabia;
| | - Eida M. Alshammari
- Department of Chemistry, College of Sciences, University of Ha’il, Ha’il 55211, Saudi Arabia;
| | - Gaber El-Saber Batiha
- Department of Pharmacology and Therapeutics, Faculty of Veterinary Medicine, Damanhour University, Damanhour 22511, Al Beheira, Egypt;
| | - Michał Tomczyk
- Department of Pharmacognosy, Medical University of Białystok, ul. Mickiewicza 2a, 15-230 Białystok, Poland;
| | - Hayder M. Al-kuraishy
- Department of Clinical Pharmacology and Medicine, College of Medicine, Al Mustanysiriyia University, Baghdad 10011, Iraq;
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Sinnadurai S, Okabayashi S, Kawamura T, Mori M, Bhoo-Pathy N, Aishah Taib N, Ukawa S, Tamakoshi A, The Jacc Study Group . Intake of Common Alcoholic and Non-Alcoholic Beverages and Breast Cancer Risk among Japanese Women: Findings from the Japan Collaborative Cohort Study. Asian Pac J Cancer Prev 2020; 21:1701-1707. [PMID: 32592367 PMCID: PMC7568889 DOI: 10.31557/apjcp.2020.21.6.1701] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Indexed: 12/13/2022] Open
Abstract
This study investigated the association between intake of common alcoholic and non-alcoholic beverages and breast cancer risk among Japanese women. This study included 33,396 Japanese women aged 40–79 years from 24 areas in Japan from the Collaborative Cohort study. During the follow-up period (≥20 years), 245 incidents or mortal breast cancers were documented. Multivariable logistic regression analysis was performed to assess the independent association between breast cancer risk and the intake of Japanese green tea, coffee, and alcohol. Japanese green tea was the most commonly consumed non-alcoholic beverage (81.6% of participants), followed by coffee (34.7%) and alcohol (23.6%). No significant associations were identified between the intake of green tea and coffee with breast cancer risk (odds ratio OR 1.15, 95% confidence interval [CI] 0.82–1.60, and OR 0.84, 95% CI 0.64–1.10, respectively). Alcohol intake was associated with significant breast cancer risk (OR 1.46, 95% CI 1.11–1.92), and even infrequent alcohol consumption (<1 times/week) was associated with substantially increased breast cancer risk (OR 2.07, 95% CI 1.39–3.09). Alcohol type, especially, wine and whisky intake tended to be marginally associated with breast cancer risk (OR 1.79, 95% CI 0.99–3.23 and [OR] 1.68, 95% CI 0.91–3.08, respectively). Alcohol consumption would be associated with increased breast cancer risk. However, intake of green tea or coffee does not appear to be associated with increased breast cancer risk.
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Affiliation(s)
- Siamala Sinnadurai
- Kyoto University Health Service, Kyoto, Japan.,Department of Social and Preventive Medicine, Faculty of Medicine, University of Malaya, Malaysia.,Department of Population Medicine and Civilization Disease Prevention, Medical University of Bialystok, Poland
| | | | | | - Mitsuru Mori
- Hokkaido Chitose College of Rehabilitation, Chitose, Japan
| | - Nirmala Bhoo-Pathy
- Julius Centre University of Malaya, Faculty of Medicine, University of Malaya, Malaysia
| | - Nur Aishah Taib
- Department of Surgery, Faculty of Medicine, University of Malaya, Malaysia.,University Malaya Cancer Research Institute, Malaysia
| | - Shigekazu Ukawa
- Department of Public Health, Hokkaido University Graduate School of Medicine, Sapporo, Japan.,Research Unit of Advanced Interdisciplinary Care Science, Graduate School of Human Life Science, Osaka City University, Osaka, Japan
| | - Akiko Tamakoshi
- Department of Public Health, Hokkaido University Graduate School of Medicine, Sapporo, Japan
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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: 39] [Impact Index Per Article: 9.8] [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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Zhang D, Nichols HB, Troester M, Cai J, Bensen JT, Sandler DP. Tea consumption and breast cancer risk in a cohort of women with family history of breast cancer. Int J Cancer 2020; 147:876-886. [PMID: 31837003 DOI: 10.1002/ijc.32824] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 11/30/2019] [Accepted: 12/04/2019] [Indexed: 02/06/2023]
Abstract
Laboratory studies have observed chemopreventive effects of black and green tea on breast cancer development, but few epidemiologic studies have identified such effects. We investigated the association between tea consumption and breast cancer risk using data from 45,744 U.S. and Puerto Rican women participating in the Sister Study. Frequency and serving size of black and green tea consumption were measured at cohort enrollment. Breast cancer diagnoses were reported during follow-up and confirmed by medical record review. Multivariable Cox proportional hazards regression was used to estimate hazard ratios (HR) and 95% confidence intervals (CI). We further investigated potential variation according to estrogen receptor (ER) status, menopausal status and body mass index (BMI). Overall, 81.6 and 56.0% of women drank black or green tea, respectively. A total of 2,809 breast cancer cases were identified in the cohort. The multivariable model suggested an inverse association between black (≥5 vs. 0 cups/week: HR = 0.88, 95% CI 0.78, 1.00, p-trend = 0.08) and green tea (≥5 vs. 0 cups/week: HR = 0.82, 95% CI 0.70, 0.95, p-trend < 0.01) consumption and breast cancer risk. We did not observe differences by ER characteristics, menopausal status or BMI. In conclusion, our study suggests drinking at least five cups of green or black tea per week may be associated with decreased breast cancer risk.
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Affiliation(s)
- Dongyu Zhang
- Department of Oncology, Georgetown University School of Medicine, Washington, DC.,Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC
| | - Hazel B Nichols
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC
| | - Melissa Troester
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC
| | - Jianwen Cai
- Department of Biostatistics, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC
| | - Jeannette T Bensen
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC
| | - Dale P Sandler
- Epidemiology Branch, National Institute of Environmental Health Sciences, Research Triangle Park, NC
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Wang Y, Zhao Y, Chong F, Song M, Sun Q, Li T, Xu L, Song C. A dose-response meta-analysis of green tea consumption and breast cancer risk. Int J Food Sci Nutr 2020; 71:656-667. [DOI: 10.1080/09637486.2020.1715353] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Yanli Wang
- Department of Epidemiology and Statistics, College of Public Health, Zhengzhou University, Zhengzhou, Henan, PR China
- Henan Key Laboratory of Tumor Epidemiology, Zhengzhou University, Zhengzhou, Henan, PR China
| | - Yanyan Zhao
- Division of Endocrinology, Department of Internal Medicine, The First Affiliated Hospital, Zhengzhou University, Zhengzhou, Henan, China
| | - Feifei Chong
- Department of Epidemiology and Statistics, College of Public Health, Zhengzhou University, Zhengzhou, Henan, PR China
- Henan Key Laboratory of Tumor Epidemiology, Zhengzhou University, Zhengzhou, Henan, PR China
| | - Mengmeng Song
- Department of Epidemiology and Statistics, College of Public Health, Zhengzhou University, Zhengzhou, Henan, PR China
- Henan Key Laboratory of Tumor Epidemiology, Zhengzhou University, Zhengzhou, Henan, PR China
| | - Qiuyu Sun
- Department of Epidemiology and Statistics, College of Public Health, Zhengzhou University, Zhengzhou, Henan, PR China
- Henan Key Laboratory of Tumor Epidemiology, Zhengzhou University, Zhengzhou, Henan, PR China
| | - Tiandong Li
- Department of Epidemiology and Statistics, College of Public Health, Zhengzhou University, Zhengzhou, Henan, PR China
- Henan Key Laboratory of Tumor Epidemiology, Zhengzhou University, Zhengzhou, Henan, PR China
| | - Linping Xu
- Department of Teaching and Research, Henan Tumor Hospital, Zhengzhou University, Zhengzhou, Henan, PR China
| | - Chunhua Song
- Department of Epidemiology and Statistics, College of Public Health, Zhengzhou University, Zhengzhou, Henan, PR China
- Henan Key Laboratory of Tumor Epidemiology, Zhengzhou University, Zhengzhou, Henan, PR China
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8
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Abe SK, Saito E, Sawada N, Tsugane S, Ito H, Lin Y, Tamakoshi A, Sado J, Kitamura Y, Sugawara Y, Tsuji I, Nagata C, Sadakane A, Shimazu T, Mizoue T, Matsuo K, Naito M, Tanaka K, Inoue M. Green tea consumption and mortality in Japanese men and women: a pooled analysis of eight population-based cohort studies in Japan. Eur J Epidemiol 2019; 34:917-926. [DOI: 10.1007/s10654-019-00545-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 07/27/2019] [Indexed: 12/31/2022]
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Ho HC, Huang CC, Lu YT, Yeh CM, Ho YT, Yang SF, Hsin CH, Lin CW. Epigallocatechin-3-gallate inhibits migration of human nasopharyngeal carcinoma cells by repressing MMP-2 expression. J Cell Physiol 2019; 234:20915-20924. [PMID: 31012106 DOI: 10.1002/jcp.28696] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 03/27/2019] [Accepted: 04/05/2019] [Indexed: 12/28/2022]
Abstract
Metastasis of the cancer cells to the regional lymph nodes parts of the body remains an important cause of treatment failure in nasopharyngeal carcinoma (NPC) patients. Epigallocatechin-3-gallate (EGCG), the most important ingredient in the green tea, has been reported to possess antioxidant and anticancer activities. However, the effects of EGCG on NPC cell metastasis are still unclear. In the present study, we examined the in vitro antimetastatic properties of EGCG on human NPC cells, NPC-39, HONE-1 and NPC-BM. The results revealed that EGCG considerably inhibited the migration abilities of three NPC cells. The matrix metalloproteinases-2 (MMP-2) activity and expression were also significantly inhibited by EGCG treatment. Furthermore, EGCG suppressed the phosphorylation of the Src signaling pathway. Moreover, blocking the Src pathway also inhibits MMP-2 expression and migration in the NPC cells. In conclusion, this study revealed that EGCG could inhibit the metastatic activity of human NPC cells by downregulating the protein expression of MMP-2 through modulation of the Src signaling pathway, suggesting that EGCG may be a potential candidate for chemoprevention of NPC.
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Affiliation(s)
- Hsu-Chueh Ho
- Department of Otolaryngology, Chung Shan Medical University Hospital, Taichung, Taiwan.,School of Medicine, Chung Shan Medical University, Taichung, Taiwan
| | - Cheng-Chen Huang
- Department of Otolaryngology, Chung Shan Medical University Hospital, Taichung, Taiwan.,School of Medicine, Chung Shan Medical University, Taichung, Taiwan
| | - Yen-Ting Lu
- Department of Otolaryngology, Chung Shan Medical University Hospital, Taichung, Taiwan.,School of Medicine, Chung Shan Medical University, Taichung, Taiwan.,Department of Otolaryngology, St. Martin De Porres Hospital, Chiayi, Taiwan
| | - Chia-Ming Yeh
- Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan
| | - Yu-Ting Ho
- Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan
| | - Shun-Fa Yang
- Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan.,Department of Medical Research, Chung Shan Medical University Hospital, Taichung, Taiwan
| | - Chung-Han Hsin
- Department of Otolaryngology, Chung Shan Medical University Hospital, Taichung, Taiwan.,School of Medicine, Chung Shan Medical University, Taichung, Taiwan
| | - Chiao-Wen Lin
- Institute of Oral Sciences, Chung Shan Medical University, Taichung, Taiwan.,Department of Dentistry, Chung Shan Medical University Hospital, Taichung, Taiwan
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10
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Samavat H, Wu AH, Ursin G, Torkelson CJ, Wang R, Yu MC, Yee D, Kurzer MS, Yuan JM. Green Tea Catechin Extract Supplementation Does Not Influence Circulating Sex Hormones and Insulin-Like Growth Factor Axis Proteins in a Randomized Controlled Trial of Postmenopausal Women at High Risk of Breast Cancer. J Nutr 2019; 149:619-627. [PMID: 30926986 PMCID: PMC6461722 DOI: 10.1093/jn/nxy316] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 11/15/2018] [Accepted: 12/14/2018] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Consumption of green tea has been associated with reduced risk of breast cancer. Hormonal modulation has been suggested as one of the potential underlying mechanisms; however, it has yet to be fully elucidated in large, long-term human clinical trials. OBJECTIVE We investigated the effects of decaffeinated green tea extract (GTE) on circulating sex hormones and insulin-like growth factor (IGF) proteins. METHODS We conducted a placebo-controlled double-blind randomized clinical trial recruiting from 8 clinical centers in Minnesota. Participants were 538 healthy postmenopausal women randomly assigned to the GTE group (463 completed the study; mean age = 60.0 y) and 537 to the placebo group (474 completed; mean age = 59.7 y). Women in the GTE group orally took 4 decaffeinated capsules containing 1315 mg total catechins including 843 mg epigallocatechin-3-gallate daily for 1 y, whereas women in the placebo group took similar capsules containing no tea catechins. Blood sex hormones (estrone, estradiol, androstenedione, testosterone, and sex hormone-binding globulin) and IGF proteins (IGF-1 and IGF binding protein-3) were quantified at baseline and months 6 (for IGF proteins only) and 12, and were assessed as secondary outcomes of the study using a mixed-effect repeated-measures ANOVA model. RESULTS Women in the GTE group had significantly higher blood total estradiol (16%; P = 0.02) and bioavailable estradiol (21%; P = 0.03) than in the placebo group at month 12. There was a statistically significant interaction between GTE supplementation and duration of treatment on estradiol and bioavailable estradiol (both Ps for interaction = 0.001). The catechol-O-methyltransferase genotype did not influence blood sex hormones before or after GTE supplementation. The circulating concentrations of IGF proteins were comparable between GTE and placebo groups at all 3 time points. CONCLUSION These results suggest that a 12-mo GTE supplementation significantly increases circulating estradiol concentrations in healthy postmenopausal women. This trial was registered at clinicaltrials.gov as NCT00917735.
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Affiliation(s)
- Hamed Samavat
- Division of Cancer Control and Population Sciences, UPMC Hillman Cancer Center, University of Pittsburgh, Pittsburgh, PA,Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA,Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN,Address correspondence to HS (e-mail: )
| | - Anna H Wu
- Department of Preventive Medicine, University of Southern California Keck School of Medicine, Los Angeles, CA
| | - Giske Ursin
- Department of Preventive Medicine, University of Southern California Keck School of Medicine, Los Angeles, CA,Cancer Registry of Norway, Oslo, Norway,Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Carolyn J Torkelson
- Department of Family Medicine and Community Health, University of Minnesota Medical School, Minneapolis, MN
| | - Renwei Wang
- Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA
| | - Mimi C Yu
- Department of Preventive Medicine, University of Southern California Keck School of Medicine, Los Angeles, CA (retired)
| | - Douglas Yee
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN,Department of Medicine, University of Minnesota, Minneapolis, MN,Department of Pharmacology, University of Minnesota, Minneapolis, MN
| | - Mindy S Kurzer
- Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN
| | - Jian-Min Yuan
- Division of Cancer Control and Population Sciences, UPMC Hillman Cancer Center, University of Pittsburgh, Pittsburgh, PA,Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA
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Green Tea Consumption and Risk of Breast Cancer and Recurrence-A Systematic Review and Meta-Analysis of Observational Studies. Nutrients 2018; 10:nu10121886. [PMID: 30513889 PMCID: PMC6316745 DOI: 10.3390/nu10121886] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2018] [Revised: 11/27/2018] [Accepted: 11/28/2018] [Indexed: 01/01/2023] Open
Abstract
Breast cancer (BC) is the most common cancer in women and several factors are involved in its onset. Green tea (GT) has been shown to have potential beneficial effects on different types of cancer. The aim of this review was to evaluate the association between GT regular consumption and risk of BC in women. The risk of BC recurrence and risk of BC in relation to menopausal status were also evaluated. A literature search of PubMed, Scopus, and Web of Science was conducted. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed to perform the systematic review and meta-analysis. Full texts were downloaded for 40 studies; however, only 13 records were included in the meta-analysis. Eight were cohort studies and five were case-control studies. The pooled sample consisted of 163,810 people. An inverse statistically significant relationship between GT and BC risk, with an Odds Ratio (OR) = 0.85 ((95% CI = 0.80–0.92), p = 0.000)), was found. Egger’s linear regression test did not show a potential publication bias (intercept 0.33, t = 0.40, p = 0.695), which was also confirmed by the symmetry of the funnel plot. Moreover, no high statistical heterogeneity (Chi2 = 31.55, df = 13, I2 = 58.79%, p = 0.003) was found. The results of this meta-analysis showed a potential protective effect of GT consumption on BC, especially for BC recurrence.
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12
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Yasuda T, Miyata Y, Nakamura Y, Sagara Y, Matsuo T, Ohba K, Sakai H. High Consumption of Green Tea Suppresses Urinary Tract Recurrence of Urothelial Cancer via Down-regulation of Human Antigen-R Expression in Never Smokers. In Vivo 2018; 32:721-729. [PMID: 29936451 DOI: 10.21873/invivo.11300] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Revised: 04/24/2018] [Accepted: 04/25/2018] [Indexed: 12/12/2022]
Abstract
BACKGROUND/AIM Smoking is a risk factor for carcinogenesis and progression of urothelial cancer (UC). Green tea polyphenol inhibits these malignant behaviors and suppresses human antigen R (HuR) expression, which is associated with malignant aggressiveness. This study aimed to clarify the anti-cancer effects of green tea based on the smoking status of UC patients. PATIENTS AND METHODS Three hundred and sixty (260 with bladder cancer, BC and 100 with upper tract UC) patients were divided into three groups based on consumption of green tea: low (<1 cup/day, n=119), middle (1-4 cup/day, n=160), and high (>5 cup/day, n=81). HuR immunoreactivity was evaluated immunohistochemically in formalin-fixed specimens. RESULTS In never smokers, multivariate analysis showed that the frequency of green tea consumption was a significant predictor (middle: hazard ratio, HR, 0.36, p=0.002; high: HR, 0.20, p=0.003) of urinary tract recurrence. A high consumption of green tea was associated with low rates of urinary tract recurrence and up-grading in UC patients. In BC, high consumption was associated with a lower risk of up-grading (p=0.011) and up-staging (p=0.041) in recurrent cancer. HuR expression in the high-consumption group was lower (p=0.019) than that in other groups. These significant findings were not detected in ever smokers. CONCLUSION High consumption of green tea suppressed urinary tract recurrence and the risks of up-grading and up-staging by recurrence in never smokers. Our results suggested that HuR expression played important roles in such mechanisms.
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Affiliation(s)
- Takuji Yasuda
- Department of Urology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Yasuyoshi Miyata
- Department of Urology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Yuichiro Nakamura
- Department of Urology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Yuji Sagara
- Department of Urology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Tomohiro Matsuo
- Department of Urology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Kojiro Ohba
- Department of Urology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Hideki Sakai
- Department of Urology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
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13
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YASUDA TAKUJI, MIYATA YASUYOSHI, NAKAMURA YUICHIRO, SAGARA YUJI, MATSUO TOMOHIRO, OHBA KOJIRO, SAKAI HIDEKI. High Consumption of Green Tea Suppresses Urinary Tract Recurrence of Urothelial Cancer via Down-regulation of Human Antigen-R Expression in Never Smokers. In Vivo 2018; 32. [PMID: 29936451 PMCID: PMC6117785 DOI: 10.21873/invivo.112300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
BACKGROUND/AIM Smoking is a risk factor for carcinogenesis and progression of urothelial cancer (UC). Green tea polyphenol inhibits these malignant behaviors and suppresses human antigen R (HuR) expression, which is associated with malignant aggressiveness. This study aimed to clarify the anti-cancer effects of green tea based on the smoking status of UC patients. PATIENTS AND METHODS Three hundred and sixty (260 with bladder cancer, BC and 100 with upper tract UC) patients were divided into three groups based on consumption of green tea: low (<1 cup/day, n=119), middle (1-4 cup/day, n=160), and high (>5 cup/day, n=81). HuR immunoreactivity was evaluated immunohistochemically in formalin-fixed specimens. RESULTS In never smokers, multivariate analysis showed that the frequency of green tea consumption was a significant predictor (middle: hazard ratio, HR, 0.36, p=0.002; high: HR, 0.20, p=0.003) of urinary tract recurrence. A high consumption of green tea was associated with low rates of urinary tract recurrence and up-grading in UC patients. In BC, high consumption was associated with a lower risk of up-grading (p=0.011) and up-staging (p=0.041) in recurrent cancer. HuR expression in the high-consumption group was lower (p=0.019) than that in other groups. These significant findings were not detected in ever smokers. CONCLUSION High consumption of green tea suppressed urinary tract recurrence and the risks of up-grading and up-staging by recurrence in never smokers. Our results suggested that HuR expression played important roles in such mechanisms.
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14
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Najaf Najafi M, Salehi M, Ghazanfarpour M, Hoseini ZS, Khadem-Rezaiyan M. The association between green tea consumption and breast cancer risk: A systematic review and meta-analysis. Phytother Res 2018; 32:1855-1864. [PMID: 29876987 DOI: 10.1002/ptr.6124] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 05/05/2018] [Accepted: 05/10/2018] [Indexed: 12/18/2022]
Abstract
This systematic review and meta-analysis aimed to critically evaluate the relation between green tea (GT) consumption and the risk of breast cancer. Popular electronic databases were systematically searched for papers in English language. All case-control and cohort studies in addition to randomized clinical trials were included if they assessed the chemopreventive effects of GT on breast cancer. The quality of included studies was assessed using the Newcastle-Ottawa and Jadad scale. This systematic review comprised 14 studies: 9 case-control studies, 4 cohort studies, and 1 clinical trial. Odds ratio (OR) in case-control studies suggested that women in the group receiving the highest level of GT had 19% reduction in breast cancer risk compared with those who received the lowest level of GT (summary OR = 0.81, p = .031; 95% CI [0.66, 0.981]; heterogeneity, I2 = 71.53, p < .001, random effect model; 9 studies). OR in cohort studies also showed no significant difference (OR = 0.99, p = .94; 95% CI [0.81, 1.138]; heterogeneity, I2 = 19.06, p = .29; fixed-effect model; 4 studies). According to the only clinical trial, treatment with GT could not alter the mammographic density compared with placebo (26% vs. 25%). It cannot be concluded that GT consumption may decrease the risk of breast cancer. Due to high heterogeneity, a pooled analysis of case-control and cohort studies was not performed.
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Affiliation(s)
- Mona Najaf Najafi
- Clinical Research Unit, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Maryam Salehi
- Clinical Research Unit, Mashhad University of Medical Sciences, Mashhad, Iran
- Cancer Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Masumeh Ghazanfarpour
- Evidence-Based Care Research Centre, Department of Midwifery, School of Nursing and Midwifery, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Zeinab Sadat Hoseini
- Student Research Committee, Faculty of Medicine, Islamic Azad University of Mashhad, Mashhad, Iran
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15
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Coffee Intake Decreases Risk of Postmenopausal Breast Cancer: A Dose-Response Meta-Analysis on Prospective Cohort Studies. Nutrients 2018; 10:nu10020112. [PMID: 29360766 PMCID: PMC5852688 DOI: 10.3390/nu10020112] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 01/16/2018] [Accepted: 01/18/2018] [Indexed: 12/18/2022] Open
Abstract
Aim: A dose-response meta-analysis was conducted in order to summarize the evidence from prospective cohort studies regarding the association between coffee intake and breast cancer risk. Methods: A systematic search was performed in electronic databases up to March 2017 to identify relevant studies; risk estimates were retrieved from the studies and linear and non-linear dose-response analysis modelled by restricted cubic splines was conducted. A stratified and subgroup analysis by menopausal and estrogen/progesterone receptor (ER/PR) status, smoking status and body mass index (BMI) were performed in order to detect potential confounders. Results: A total of 21 prospective studies were selected either for dose-response, the highest versus lowest category of consumption or subgroup analysis. The dose-response analysis of 13 prospective studies showed no significant association between coffee consumption and breast cancer risk in the non-linear model. However, an inverse relationship has been found when the analysis was restricted to post-menopausal women. Consumption of four cups of coffee per day was associated with a 10% reduction in postmenopausal cancer risk (relative risk, RR 0.90; 95% confidence interval, CI 0.82 to 0.99). Subgroup analyses showed consistent results for all potential confounding factors examined. Conclusions: Findings from this meta-analysis may support the hypothesis that coffee consumption is associated with decreased risk of postmenopausal breast cancer.
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16
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Coffee Intake Decreases Risk of Postmenopausal Breast Cancer: A Dose-Response Meta-Analysis on Prospective Cohort Studies. Nutrients 2018. [PMID: 29360766 DOI: 10.3390/nu10020112,] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Aim: A dose-response meta-analysis was conducted in order to summarize the evidence from prospective cohort studies regarding the association between coffee intake and breast cancer risk. Methods: A systematic search was performed in electronic databases up to March 2017 to identify relevant studies; risk estimates were retrieved from the studies and linear and non-linear dose-response analysis modelled by restricted cubic splines was conducted. A stratified and subgroup analysis by menopausal and estrogen/progesterone receptor (ER/PR) status, smoking status and body mass index (BMI) were performed in order to detect potential confounders. Results: A total of 21 prospective studies were selected either for dose-response, the highest versus lowest category of consumption or subgroup analysis. The dose-response analysis of 13 prospective studies showed no significant association between coffee consumption and breast cancer risk in the non-linear model. However, an inverse relationship has been found when the analysis was restricted to post-menopausal women. Consumption of four cups of coffee per day was associated with a 10% reduction in postmenopausal cancer risk (relative risk, RR 0.90; 95% confidence interval, CI 0.82 to 0.99). Subgroup analyses showed consistent results for all potential confounding factors examined. Conclusions: Findings from this meta-analysis may support the hypothesis that coffee consumption is associated with decreased risk of postmenopausal breast cancer.
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17
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Sinha D, Biswas J, Nabavi SM, Bishayee A. Tea phytochemicals for breast cancer prevention and intervention: From bench to bedside and beyond. Semin Cancer Biol 2017; 46:33-54. [DOI: 10.1016/j.semcancer.2017.04.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Revised: 03/25/2017] [Accepted: 04/01/2017] [Indexed: 02/06/2023]
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18
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19
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Clay PG, Glaros AG, Clauson KA. Perceived Efficacy, Indications, and Information Sources for Medically Indigent Patients and Their Healthcare Providers Regarding Dietary Supplements. Ann Pharmacother 2016; 40:427-32. [PMID: 16507626 DOI: 10.1345/aph.1e497] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Background: Evidence exists that medically indigent and minority patients use dietary supplements at rates as high or higher than that of the general population. Safety concerns regarding the use of dietary supplements are further exacerbated by a suboptimal level of patient disclosure and provider inquiry. Objective: To determine dietary supplement use, indications, perceived efficacy, and information sources of patients and providers using a pilot study in a clinic for the medically indigent. Methods: Five hundred self-administered patient surveys and 50 healthcare provider surveys were made available to any patient at a free health clinic in Kansas City, MO. Surveys were collected and descriptive analyses were performed. Results: Three hundred eleven patient surveys were returned. Of the 37.3% (116/311) of respondents who had used dietary supplements, 13.8% (n = 16) had 10 comorbid conditions. Ninety-six dietary supplements were used for 8 medical condition categories. The 9 agents most frequently reported used were garlic (n = 32), aloe/green tea (n = 27 each), chamomile/echinacea (n = 24 each), St. John's wort (n = 22), ginseng (n = 18), and cranberry/Ginkgo biloba (n = 17 each). Patients reported a broad range of indications for taking dietary supplements. Patients reported (mean ± SD) 2.37 ± 4.23 agents as effective and 0.78 ± 1.73 as ineffective or harmful. Provider surveys revealed that 60% (21/35) and 74% (26/35) were currently or had ever used dietary supplements, respectively. Fifty-seven percent (20/35) of providers reported attending educational programs on dietary supplements, and providers perceived patient supplement use to be most influenced by advertisements (40%) and friends (40%). Conclusions: The medically indigent population uses a wide variety of dietary supplements. There is little consistency in perceived indications, which may prevent clinicians from accurately predicting specific herbal use rationale given any individual's or population's set of comorbid conditions. Clinicians are encouraged to accurately determine their individual practice setting's use pattern.
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Affiliation(s)
- Patrick G Clay
- Associate Professor and Director of Dybedal Clinical Research Center, Kansas City, MO, USA.
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20
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Xiang LP, Wang A, Ye JH, Zheng XQ, Polito CA, Lu JL, Li QS, Liang YR. Suppressive Effects of Tea Catechins on Breast Cancer. Nutrients 2016; 8:nu8080458. [PMID: 27483305 PMCID: PMC4997373 DOI: 10.3390/nu8080458] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 07/20/2016] [Accepted: 07/22/2016] [Indexed: 12/15/2022] Open
Abstract
Tea leaf (Camellia sinensis) is rich in catechins, which endow tea with various health benefits. There are more than ten catechin compounds in tea, among which epigallocatechingallate (EGCG) is the most abundant. Epidemiological studies on the association between tea consumption and the risk of breast cancer were summarized, and the inhibitory effects of tea catechins on breast cancer, with EGCG as a representative compound, were reviewed in the present paper. The controversial results regarding the role of tea in breast cancer and areas for further study were discussed.
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Affiliation(s)
- Li-Ping Xiang
- Tea Research Institute, Zhejiang University, # 866 Yuhangtang Road, Hangzhou 310058, China.
- National Tea and Tea product Quality Supervision and Inspection Center (Guizhou), Zunyi 563100, China.
| | - Ao Wang
- National Tea and Tea product Quality Supervision and Inspection Center (Guizhou), Zunyi 563100, China.
| | - Jian-Hui Ye
- Tea Research Institute, Zhejiang University, # 866 Yuhangtang Road, Hangzhou 310058, China.
| | - Xin-Qiang Zheng
- Tea Research Institute, Zhejiang University, # 866 Yuhangtang Road, Hangzhou 310058, China.
| | - Curt Anthony Polito
- Tea Research Institute, Zhejiang University, # 866 Yuhangtang Road, Hangzhou 310058, China.
| | - Jian-Liang Lu
- Tea Research Institute, Zhejiang University, # 866 Yuhangtang Road, Hangzhou 310058, China.
| | - Qing-Sheng Li
- Tea Research Institute, Zhejiang University, # 866 Yuhangtang Road, Hangzhou 310058, China.
| | - Yue-Rong Liang
- Tea Research Institute, Zhejiang University, # 866 Yuhangtang Road, Hangzhou 310058, China.
- National Tea and Tea product Quality Supervision and Inspection Center (Guizhou), Zunyi 563100, China.
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Seely D, Mills EJ, Wu P, Verma S, Guyatt GH. The Effects of Green Tea Consumption on Incidence of Breast Cancer and Recurrence of Breast Cancer: A Systematic Review and Meta-analysis. Integr Cancer Ther 2016; 4:144-55. [PMID: 15911927 DOI: 10.1177/1534735405276420] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Background: Green tea is widely used by women for the prevention and treatment of breast cancer. The authors aimed to determine the efficacy of green tea ingestion on the risk of breast cancer development and the risk of breast cancer recurrence. Methods: The authors conducted a systematic review and meta-analyses of observational studies from systematic searches of 8 electronic data sources and contact with authors. They included studies assessing breast cancer incidence and recurrence. Results from cohort studies and case-control studies were pooled separately using a random effects model with testing of a priori hypotheses to explain heterogeneity. Results: The pooled relative risk (RR) of developing breast cancer for the highest levels of green tea consumption in cohort studies was 0.89 (95% confidence interval [CI], 0.71-1.1; P= .28; I2= 0%), and in case control studies, the odds ratio was 0.44 (95% CI, 0.14-1.31; P= .14; I2= 47%). The pooled RR of cohort studies for breast cancer recurrence in all stages was 0.75 (95% CI, 0.47-1.19; P= .22; I2= 37%). A subgroup analysis of recurrence in stage I and II disease showed a pooled RR in cohort studies of 0.56 (95% CI, 0.38-0.83; P= .004; I2= 0%). Dose-response relationships were evident in only 3 of the 7 studies. Conclusion: To date, the epidemiological data indicates that consumption of 5 or more cups of green tea a day shows a non-statistically significant trend towards the prevention of breast cancer development. Evidence indicates that green tea consumption may possibly help prevent breast cancer recurrence in early stage (I and II) cancers. However, conclusions as to the potential therapeutic application of green tea are currently impossible to make due to the small number of studies conducted, the lack of any clinical trial evidence, the lack of a consistent dose-response relationship, and the potential for interaction with standard care.
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Affiliation(s)
- Dugald Seely
- Department of Clinical Epidemiology, Canadian College of Naturopathic Medicine, Toronto, Ontario, Canada.
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22
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Chen ZM, Lin Z. Tea and human health: biomedical functions of tea active components and current issues. J Zhejiang Univ Sci B 2015; 16:87-102. [PMID: 25644464 DOI: 10.1631/jzus.b1500001] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Originating in China, tea and tea planting have spread throughout the world since the middle of the Tang dynasty. Now people from 160 countries in the world are accustomed to tea drinking. A brief history of tea's medicinal role in China and its spread to the world are introduced. The effectiveness of tea active components and tea drinking on major human diseases, including cancer, metabolic syndrome, cardiovascular disease, and neurodegenerative diseases, is discussed. Also presented are some related issues, such as the bioavailability of tea active components, the new formulations of tea polyphenols, and the safety for consumers of dietary supplements containing tea polyphenols.
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Affiliation(s)
- Zong-mao Chen
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China
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23
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Amitani M, Amitani H, Sloan RA, Suzuki H, Sameshima N, Asakawa A, Nerome Y, Owaki T, Inui A, Hoshino E. The translational aspect of complementary and alternative medicine for cancer with particular emphasis on Kampo. Front Pharmacol 2015; 6:150. [PMID: 26300773 PMCID: PMC4527580 DOI: 10.3389/fphar.2015.00150] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 07/09/2015] [Indexed: 12/17/2022] Open
Abstract
Complementary and alternative medicine (CAM) including Japanese Kampo is known to have anticancer potential. An increasing number of cancer survivors are using CAM for disease prevention, immune system enhancement, and symptom control. Although there have been abundant previous clinical reports regarding CAM, scientific investigations aimed at acquiring quantifiable results in clinical trials, as well as basic research regarding CAM, have only recently been undertaken. Recent studies suggest that CAM enhancement of immune function is related to cytokines. This review provides a translational aspect of CAM, particularly Hozai in Kampo from both scientific and clinical points of view for further development of CAM for cancer treatment.
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Affiliation(s)
- Marie Amitani
- Education Center for Doctors in Remote Islands and Rural Areas, Kagoshima University Graduate School of Medical and Dental Sciences Kagoshima, Japan ; Department of Psychosomatic Internal Medicine, Kagoshima University Graduate School of Medical and Dental Sciences Kagoshima, Japan
| | - Haruka Amitani
- Department of Psychosomatic Internal Medicine, Kagoshima University Graduate School of Medical and Dental Sciences Kagoshima, Japan
| | - Robert A Sloan
- Department of Psychosomatic Internal Medicine, Kagoshima University Graduate School of Medical and Dental Sciences Kagoshima, Japan
| | - Hajime Suzuki
- Department of Psychosomatic Internal Medicine, Kagoshima University Graduate School of Medical and Dental Sciences Kagoshima, Japan
| | - Nanami Sameshima
- Department of Psychosomatic Internal Medicine, Kagoshima University Graduate School of Medical and Dental Sciences Kagoshima, Japan
| | - Akihiro Asakawa
- Department of Psychosomatic Internal Medicine, Kagoshima University Graduate School of Medical and Dental Sciences Kagoshima, Japan
| | - Yasuhito Nerome
- Education Center for Doctors in Remote Islands and Rural Areas, Kagoshima University Graduate School of Medical and Dental Sciences Kagoshima, Japan
| | - Tetsuhiro Owaki
- Education Center for Doctors in Remote Islands and Rural Areas, Kagoshima University Graduate School of Medical and Dental Sciences Kagoshima, Japan
| | - Akio Inui
- Department of Psychosomatic Internal Medicine, Kagoshima University Graduate School of Medical and Dental Sciences Kagoshima, Japan
| | - Etsuo Hoshino
- Division of Kampo Support, Cancer Institute Hospital Tokyo, Japan
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Oh JK, Sandin S, Ström P, Löf M, Adami HO, Weiderpass E. Prospective study of breast cancer in relation to coffee, tea and caffeine in Sweden. Int J Cancer 2015; 137:1979-89. [PMID: 25885188 DOI: 10.1002/ijc.29569] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 04/07/2015] [Indexed: 02/01/2023]
Abstract
Studies of coffee and tea consumption and caffeine intake as risk factors for breast cancer are inconclusive. We assessed coffee and tea consumption, caffeine intake, and possible confounding factors among 42,099 women from the Swedish Women's Lifestyle and Health study, the participants of which were aged 30-49 years at enrollment in 1991-1992. Complete follow-up for breast cancer incidence was performed through 2012 via linkage to national registries. Poisson regression models were used to estimate relative risks (RRs) and 95% confidence intervals (CIs) for breast cancer. During follow-up 1,395 breast cancers were diagnosed. The RR was 0.97 (95% CI 0.94-0.99) for a 1-unit increase in cups of coffee/day, 1.14 (95% CI 1.05-1.24) for a 1-unit increase in cups of tea/day, and 0.97 (95% CI 0.95-1.00) for a 100 mg/day increase in caffeine intake. Although the RR for no consumption (RR = 0.86, 95% CI 0.69-1.08), a group with a relatively small number of women, was not statistically significant, women with higher consumption had a decreased breast cancer risk (3-4 cups/day: RR = 0.87, 95% CI 0.76-1.00; ≥5 cups/day: RR = 0.81, 95% CI 0.70-0.94) compared to women consuming 1-2 cups of coffee/day. Compared to no consumption, women consuming >1 cups tea/day showed an increased breast cancer risk (RR = 1.19, 95% CI 1.00-1.42). Similar patterns of estimates were observed for breast cancer risk overall, during pre- and postmenopausal years, and for ER+ or PR+ breast cancer, but not for ER- and PR- breast cancer. Our findings suggest that coffee consumption and caffeine intake is negatively associated with the risk of overall and ER+/PR- breast cancer, and tea consumption is positively associated with the risk of overall and ER+/PR+ breast cancer.
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Affiliation(s)
- Jin-Kyoung Oh
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.,Department of Cancer Control Policy, Graduate School of Cancer Science and Policy, and National Cancer Control Institute, National Cancer Center, Goyang, Republic of Korea
| | - Sven Sandin
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Peter Ström
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Marie Löf
- Department of Biosciences and Nutrition, Karolinska Institutet, Stockholm, Sweden
| | - Hans-Olov Adami
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.,Department of Epidemiology, Harvard School of Public Health, Boston, MA, USA
| | - Elisabete Weiderpass
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.,Department of Research, The Cancer Registry of Norway, Oslo, Norway.,Department of Genetic Epidemiology, Folkhälsan Research Center, Helsinki, Finland.,Department of Community Medicine, Faculty of Health Sciences, University of Tromsø, The Arctic University of Norway, Tromsø, Norway
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Li MJ, Yin YC, Wang J, Jiang YF. Green tea compounds in breast cancer prevention and treatment. World J Clin Oncol 2014; 5:520-528. [PMID: 25114865 PMCID: PMC4127621 DOI: 10.5306/wjco.v5.i3.520] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/25/2013] [Revised: 02/12/2014] [Accepted: 04/09/2014] [Indexed: 02/06/2023] Open
Abstract
Breast cancer is the most common cancer among women. In recent years, many in vitro and in vivo studies indicate that green tea possesses anti-cancer effects. The epidemiological studies, however, have produced inconclusive results in humans. Likewise, results from animal models about the preventive or therapeutic effects of green tea components are inconclusive. The mechanisms by which green tea intake may influence the risk of breast cancer in humans remain elusive mechanisms by which green tea intake may influence. Here, we review recent studies of green tea polyphenols and their applications in the prevention and treatment of breast cancer. Furthermore, we discuss the effect of green tea components on breast cancer by reviewing epidemiological studies, animal model studies and clinical trials. At last, we discuss the mechanisms by which green tea components suppress the development and recurrence of breast cancer. A better understanding of the mechanisms will improve the utilization of green tea in breast cancer prevention and therapy and pave the way to novel prevention and treatment strategies for breast cancer.
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Nie XC, Dong DS, Bai Y, Xia P. Meta-Analysis of Black Tea Consumption and Breast Cancer Risk: Update 2013. Nutr Cancer 2014; 66:1009-14. [DOI: 10.1080/01635581.2014.936947] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Yu F, Jin Z, Jiang H, Xiang C, Tang J, Li T, He J. Tea consumption and the risk of five major cancers: a dose-response meta-analysis of prospective studies. BMC Cancer 2014; 14:197. [PMID: 24636229 PMCID: PMC4004325 DOI: 10.1186/1471-2407-14-197] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 03/11/2014] [Indexed: 12/14/2022] Open
Abstract
Background We conducted a dose–response meta-analysis of prospective studies to summarize evidence of the association between tea consumption and the risk of breast, colorectal, liver, prostate, and stomach cancer. Methods We searched PubMed and two other databases. Prospective studies that reported risk ratios (RRs) with 95% confidence intervals (CIs) of cancer risk for ≥3 categories of tea consumption were included. We estimated an overall RR with 95% CI for an increase of three cups/day of tea consumption, and, usingrestricted cubic splines, we examined a nonlinear association between tea consumption and cancer risk. Results Forty-one prospective studies, with a total of 3,027,702 participants and 49,103 cancer cases, were included. From the pooled overall RRs, no inverse association between tea consumption and risk of five major cancers was observed. However, subgroup analysis showed that increase in consumption of three cups of black tea per day was a significant risk factor for breast cancer (RR, 1.18; 95% CI, 1.05-1.32). Conclusion Ourresults did not show a protective role of tea in five major cancers. Additional large prospective cohort studies are needed to make a convincing case for associations.
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Affiliation(s)
| | | | | | | | | | | | - Jia He
- Department of Health Statistics, Second Military Medical University, 800 Xiangyin Road, Shanghai 200433, China.
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Gao Y, Huang YB, Liu XO, Chen C, Dai HJ, Song FJ, Wang J, Chen KX, Wang YG. Tea Consumption, Alcohol Drinking and Physical Activity Associations with Breast Cancer Risk among Chinese Females: a Systematic Review and Meta-analysis. Asian Pac J Cancer Prev 2013; 14:7543-50. [DOI: 10.7314/apjcp.2013.14.12.7543] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Iwasaki M, Mizusawa J, Kasuga Y, Yokoyama S, Onuma H, Nishimura H, Kusama R, Tsugane S. Green tea consumption and breast cancer risk in Japanese women: a case-control study. Nutr Cancer 2013; 66:57-67. [PMID: 24274352 DOI: 10.1080/01635581.2014.847963] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Although many in vitro and animal studies have suggested a protective effect of green tea against breast cancer, only a few epidemiological studies have examined this association, and findings have been inconsistent. We examined the association between green tea consumption and breast cancer risk in consideration of the hormone receptor status of tumors and investigated whether the association was modified by dietary and genetic factors based on a hospital-based case-control study in Nagano, Japan. A total of 369 pairs completed a validated food frequency questionnaire and provided blood samples. Four single nucleotide polymorphisms (SNPs) were genotyped: CYP19A1 (rs10046), COMT (rs4680), MTHFR C677T (rs1801133), and MTHFR A1298C (rs1801131). We found no inverse association between green tea consumption and breast cancer risk. Compared with women who drank less than 120 ml of green tea per day, the adjusted odds ratio for women who drank more than 600 ml was 1.27 (95% confidence interval = 0.75-2.14; P for trend = 0.20). We also found no inverse association for either tumor subtype. No substantial effect modification was observed for menopausal status, 4 SNPs, or dietary intake of folate or isoflavone. This study provides additional evidence that green tea consumption is not associated with a decreased risk.
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Affiliation(s)
- Motoki Iwasaki
- a Epidemiology and Prevention Division, Research Center for Cancer Prevention and Screening , National Cancer Center , Tokyo , Japan
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Shahabi M, Rafiee S, Mohtasebi SS, Hosseinpour S. Image analysis and green tea color change kinetics during thin-layer drying. FOOD SCI TECHNOL INT 2013; 20:465-76. [PMID: 23751546 DOI: 10.1177/1082013213492524] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
This study was conducted to investigate the effect of air temperature and air flow velocity on kinetics of color parameter changes during hot-air drying of green tea, to obtain the best model for hot-air drying of green tea, to apply a computer vision system and to study the color changes during drying. In the proposed computer vision system system, at first RGB values of the images were converted into XYZ values and then to Commission International d'Eclairage L*a*b* color coordinates. The obtained color parameters of L*, a* and b* were calibrated with Hunter-Lab colorimeter. These values were also used for calculation of the color difference, chroma, hue angle and browning index. The values of L* and b* decreased, while the values of a* and color difference (ΔE*ab ) increased during hot-air drying. Drying data were fitted to three kinetic models. Zero, first-order and fractional conversion models were utilized to describe the color changes of green tea. The suitability of fitness was determined using the coefficient of determination (R (2)) and root-mean-square error. Results showed that the fraction conversion model had more acceptable fitness than the other two models in most of color parameters.
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Affiliation(s)
| | - Shahin Rafiee
- Department of Mechanical Engineering of Agricultural Machinery, Faculty of Agricultural Engineering and Technology, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
| | - Seyed Saeid Mohtasebi
- Department of Mechanical Engineering of Agricultural Machinery, Faculty of Agricultural Engineering and Technology, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
| | - Soleiman Hosseinpour
- Department of Mechanical Engineering of Agricultural Machinery, Faculty of Agricultural Engineering and Technology, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
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Wu Y, Zhang D, Kang S. Black tea, green tea and risk of breast cancer: an update. SPRINGERPLUS 2013; 2:240. [PMID: 23750333 PMCID: PMC3671100 DOI: 10.1186/2193-1801-2-240] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 04/29/2013] [Indexed: 01/19/2023]
Abstract
Previous meta-analysis indicated conflicting results in case–control versus cohort studies on the association of green tea with breast cancer risk, and conflicting results were also found in case–control versus cohort studies in another meta-analysis on the association of black tea with breast cancer risk. Many studies were published after the previous meta-analysis. Besides, the dose-response relationship of tea consumption with breast cancer risk is unclear. Thus the association of tea consumption with breast cancer risk was assessed incorporating new publications. Summary relative risk (RR) for highest versus lowest level of tea consumption was calculated based on fixed or random effect models. Dose-response relationship was assessed by restricted cubic spline model and multivariate random-effect meta-regression. The combined results from 9 studies suggested no significant association between green tea consumption and breast cancer risk (RR = 0.82, 95% CI = 0.64-1.04). No significant association was found among cohort studies and case-control studies after sensitivity analysis, respectively. A linear but not significant dose-response association was found between green tea consumption and breast cancer risk. The combined results from 25 studies demonstrated no significant association between black tea consumption and breast cancer risk (RR = 0.98, 95% CI = 0.93-1.03), and no significant association was found in subgroup analysis. A linear but not significant dose-response association was found between black tea consumption and breast cancer risk. Based on the current evidence, black tea and green tea might not contribute significantly to breast cancer risk, respectively.
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Affiliation(s)
- Yili Wu
- Department of Epidemiology and Health Statistics, The Medical College of Qingdao University, Dongzhou Road, No.38, Shandong Qingdao, 266021 P. R. China
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de Pace RCC, Liu X, Sun M, Nie S, Zhang J, Cai Q, Gao W, Pan X, Fan Z, Wang S. Anticancer activities of (-)-epigallocatechin-3-gallate encapsulated nanoliposomes in MCF7 breast cancer cells. J Liposome Res 2013; 23:187-96. [PMID: 23600473 DOI: 10.3109/08982104.2013.788023] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The chemopreventive actions exerted by green tea are thought to be due to its major polyphenol, (-)-epigallocatechin-3-gallate (EGCG). However, the low level of stability and bioavailability in the body makes administering EGCG at chemopreventive doses unrealistic. We synthesized EGCG encapsulated chitosan-coated nanoliposomes (CSLIPO-EGCG), and observed their antiproliferative and proapoptotic effect in MCF7 breast cancer cells. CSLIPO-EGCG significantly enhanced EGCG stability, improved sustained release, increased intracellular EGCG content in MCF7 cells, induced apoptosis of MCF7 cells, and inhibited MCF7 cell proliferation compared to native EGCG and void CSLIPO. The CSLIPO-EGCG retained its antiproliferative and proapoptotic effectiveness at 10 μM or lower, at which native EGCG does not have any beneficial effects. This study portends a potential breakthrough in the prevention or even treatment of breast cancer by using biocompatible and biodegradable CSLIPO-EGCG with enhanced chemopreventive efficacy and minimized immunogenicity and side-effects.
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Jiang W, Wu Y, Jiang X. Coffee and caffeine intake and breast cancer risk: an updated dose-response meta-analysis of 37 published studies. Gynecol Oncol 2013; 129:620-9. [PMID: 23535278 DOI: 10.1016/j.ygyno.2013.03.014] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Revised: 03/14/2013] [Accepted: 03/17/2013] [Indexed: 01/31/2023]
Abstract
OBJECTIVE We conducted an updated meta-analysis to summarize the evidence from published studies regarding the association of coffee and caffeine intake with breast cancer risk. METHODS Pertinent studies were identified by a search of PubMed and by reviewing the reference lists of retrieved articles. The fixed or random effect model was used based on heterogeneity test. The dose-response relationship was assessed by restricted cubic spline model and multivariate random-effect meta-regression. RESULTS 37 published articles, involving 59,018 breast cancer cases and 966,263 participants, were included in the meta-analysis. No significant association was found between breast cancer risk and coffee (RR=0.97, P=0.09), decaffeinated coffee (RR=0.98, P=0.55) and caffeine (RR=0.99, P=0.73), respectively. And the association was still not significant when combining coffee and caffeine (coffee/caffeine) (RR=0.97, P=0.09). However, an inverse association of coffee/caffeine with breast cancer risk was found for postmenopausal women (RR=0.94, P=0.02), and a strong and significant association of coffee with breast cancer risk was found for BRCA1 mutation carriers (RR=0.69, P<0.01). A linear dose-response relationship was found for breast cancer risk with coffee and caffeine, and the risk of breast cancer decreased by 2% (P=0.05) for every 2 cups/day increment in coffee intake, and 1% (P=0.52) for every 200mg/day increment in caffeine intake, respectively. CONCLUSIONS Findings from this meta-analysis suggested that coffee/caffeine might be weakly associated with breast cancer risk for postmenopausal women, and the association for BRCA1 mutation carriers deserves further investigation.
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Affiliation(s)
- Wenjie Jiang
- Department of Epidemiology and Health Statistics, the Medical College of Qingdao University, Shandong, Qingdao, Dongzhou Road No. 38, PR China.
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Green tea intake is associated with urinary estrogen profiles in Japanese-American women. Nutr J 2013; 12:25. [PMID: 23413779 PMCID: PMC3584908 DOI: 10.1186/1475-2891-12-25] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Accepted: 12/30/2012] [Indexed: 01/19/2023] Open
Abstract
Scope Intake of green tea may reduce the risk of breast cancer; polyphenols in this drink can influence enzymes that metabolize estrogens, known causal factors in breast cancer etiology. Methods and results We examined the associations of green tea intake (<1 time/week, 1-6 times weekly, or 7+ times weekly) with urinary estrogens and estrogen metabolites (jointly EM) in a cross-sectional sample of healthy Japanese American women, including 119 premenopausal women in luteal phase and 72 postmenopausal women. We fit robust regression models to each log-transformed EM concentration (picomoles per mg creatinine), adjusting for age and study center. In premenopausal women, intake of green tea was associated with lower luteal total EM (P trend = 0.01) and lower urinary 16-pathway EM (P trend = 0.01). In postmenopausal women, urinary estrone and estradiol were approximately 20% and 40% lower (P trend = 0.01 and 0.05, respectively) in women drinking green tea daily compared to those drinking <1 time/week. Adjustment for potential confounders (age at menarche, parity/age at first birth, body mass index, Asian birthplace, soy) did not change these associations. Conclusions Findings suggest that intake of green tea may modify estrogen metabolism or conjugation and in this way may influence breast cancer risk.
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Coffee consumption and risk of breast cancer: an up-to-date meta-analysis. PLoS One 2013; 8:e52681. [PMID: 23308117 PMCID: PMC3537715 DOI: 10.1371/journal.pone.0052681] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Accepted: 11/19/2012] [Indexed: 12/01/2022] Open
Abstract
Objectives This updated meta-analysis was conducted to assess the association between coffee consumption and breast cancer risk. Methods We conducted a systematic search updated July 2012 to identify observational studies providing quantitative estimates for breast cancer risk in relation to coffee consumption. Pooled relative risks (RRs) with 95% confidence intervals (CIs) were calculated using a random-effects model, and generalized least square trend estimation was used to assess dose–response relationships. Results A total of 26 studies (16 cohort and 10 case–control studies) on coffee intake with 49497 breast cancer cases were included in the meta-analysis. The pooled RR showed a borderline significant influence of highest coffee consumption (RR = 0.96; 95% CI 0.93–1.00), low-to moderate coffee consumption (RR = 0.99; 95% CI 0.95–1.04), or an increment of 2 cups/day of coffee consumption (RR = 0.98; 95% CI 0.97–1.00) on the risk of breast cancer. In stratified analysis, a significant inverse association was observed in ER-negative subgroup. However, no significant association was noted in the others. Conclusions Our findings suggest that increased coffee intake is not associated with a significantly reduced risk of breast cancer, but we observe an inverse association in ER-negative subgroup analysis. More large studies are needed to determine subgroups to obtain more valuable data on coffee drinking and breast cancer risk.
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Abstract
Tea is one of the most consumed beverages worldwide, and green tea is the least processed from the buds of the Camellia sinensis plant. The most abundant component of green tea is (-)-epigallocatechin-3-gallate (EGCG), which has been the focus of many cell culture, animal and clinical trials, revealing that EGCG possesses antiproliferative, antimutagenic, antioxidant, antibacterial, antiviral and chemopreventive effects. In this review we briefly summarize the mechanism of action(s) of the green tea component EGCG, highlighting recent advances in the epigenetic regulation by EGCG. Additionally, we provide an overview of mouse chemoprevention studies and EGCG chemoprevention clinical trials.
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Affiliation(s)
- Laura Schramm
- Department of Biological Sciences, St. John's University, NY 11439, USA
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Ho YS, Lee CH, Wu CH. The Alpha 9-Nicotinic Acetylcholine Receptor Serves as a Molecular Target for Breast Cancer Therapy. ACTA ACUST UNITED AC 2011. [DOI: 10.1016/j.jecm.2011.10.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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Li Y, Chang SC, Goldstein BY, Scheider WL, Cai L, You NCY, Tarleton HP, Ding B, Zhao J, Wu M, Jiang Q, Yu S, Rao J, Lu QY, Zhang ZF, Mu L. Green tea consumption, inflammation and the risk of primary hepatocellular carcinoma in a Chinese population. Cancer Epidemiol 2011; 35:362-8. [PMID: 21315679 PMCID: PMC3396119 DOI: 10.1016/j.canep.2011.01.005] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Revised: 12/27/2010] [Accepted: 01/11/2011] [Indexed: 12/22/2022]
Abstract
OBJECTIVE Green tea has been found to possess anti-inflammatory, anti-oxidative and anti-carcinogenic properties. The present study examines the association between green tea drinking and hepatocellular carcinoma (HCC) and its interactions with other risk or protective factors and single nucleotide polymorphisms (SNP) of inflammation and oxidative stress related genes. METHODS A population-based case-control study with 204 primary HCC cases and 415 healthy controls was conducted in Taixing, China. Epidemiological data were collected using a standard questionnaire. SNPs of genes of the inflammation and metabolic pathways were genotyped at the UCLA Molecular Epidemiology Laboratory. Logistic regression was performed to estimate adjusted odds ratios and 95% confidence intervals. RESULTS Longer duration and larger quantities of green tea consumption were inversely associated with primary HCC. Individuals who drank green tea longer than 30 years were at lowest risk (adjusted OR=0.44, 95% CI: 0.19-0.96) compared with non-drinkers. A strong interaction was observed between green tea drinking and alcohol consumption (adjusted OR for interaction=3.40, 95% CI: 1.26-9.16). Green tea drinking was also observed to have a potential effect modification on HBV/HCV infection, smoking and polymorphisms of inflammation related cytokines, especially for IL-10. CONCLUSION Green tea consumption may protect against development of primary HCC. Potential effect modifications of green tea on associations between primary HCC and alcohol drinking, HBV/HCV infection, and inflammation-related SNPs were suggested.
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Affiliation(s)
- Yanli Li
- Department of Social and Preventive Medicine, The State University of New York (SUNY) at Buffalo, NY, USA
| | - Shen-Chih Chang
- Department of Epidemiology, School of Public Health, University of California, Los Angeles (UCLA), Los Angeles, CA, USA
| | - Binh Y. Goldstein
- Department of Epidemiology, School of Public Health, University of California, Los Angeles (UCLA), Los Angeles, CA, USA
| | - William L. Scheider
- Department of Social and Preventive Medicine, The State University of New York (SUNY) at Buffalo, NY, USA
| | - Lin Cai
- Department of Epidemiology, School of Public Health, Fujian Medical University, Fuzhou, Fijian, China
| | - Nai-Chieh Y. You
- Department of Epidemiology, School of Public Health, University of California, Los Angeles (UCLA), Los Angeles, CA, USA
| | - Heather P. Tarleton
- Department of Epidemiology, School of Public Health, University of California, Los Angeles (UCLA), Los Angeles, CA, USA
| | - Baoguo Ding
- Taixing City Center for Disease Control and Prevention (CDC), Taixing City, Jiangsu, China
| | - Jinkou Zhao
- Jiangsu Center for Disease Control and Prevention (CDC), Nanjing, Jiangsu, China
| | - Ming Wu
- Jiangsu Center for Disease Control and Prevention (CDC), Nanjing, Jiangsu, China
| | - Qingwu Jiang
- Fudan University School of Public Health, Shanghai, China
| | - Shunzhang Yu
- Fudan University School of Public Health, Shanghai, China
| | - Jianyu Rao
- Department of Pathology and Lab Med, School of Medicine, University of California, Los Angeles (UCLA), Los Angeles, CA, USA
| | - Qing-Yi Lu
- Center for Human Nutrition, School of Medicine, University of California, Los Angeles (UCLA), Los Angeles, CA, USA
| | - Zuo-Feng Zhang
- Department of Epidemiology, School of Public Health, University of California, Los Angeles (UCLA), Los Angeles, CA, USA
| | - Lina Mu
- Department of Social and Preventive Medicine, The State University of New York (SUNY) at Buffalo, NY, USA
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Iwasaki M, Tsugane S. Risk factors for breast cancer: epidemiological evidence from Japanese studies. Cancer Sci 2011; 102:1607-14. [PMID: 21624009 DOI: 10.1111/j.1349-7006.2011.01996.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Although our understanding of the etiology of breast cancer has improved, many well-known risk factors are not modifiable and present knowledge has proved insufficient to allow the disease to be overcome. Indeed, incidence and mortality among Japanese women have increased over the past three decades. Here, we review epidemiological evidence from our cohort and case-control studies among Japanese women in comparison with other published findings. Our studies confirm the important role of established factors derived primarily from Western populations, such as menstrual and reproductive factors, anthropometric factors, physical activity, and alcohol intake, in the development of breast cancer. In addition, we provide further evidence to better understand the role of traditional Japanese foods in the etiology of breast cancer. Our cohort study found that a higher intake of isoflavone and higher levels of plasma genistein, but not daidzein, were associated with a decreased risk of breast cancer. Our case-control studies reveal a dose-response pattern for these compounds; specifically, decreased risk as women move from "no" to "moderate" intake and leveling off thereafter. In addition, gene-environment interactions have been revealed in the effects of isoflavones. The evidence reviewed suggests that isoflavone has a protective effect against breast cancer in Asian populations. Conversely, our cohort study did not observe an inverse association between breast cancer risk and the intake of green tea and/or the plasma level of tea polyphenols, but we did find an association between increased risk and active and passive smoking. In conclusion, based on current knowledge, primary prevention according to individual lifestyle modification should focus on alcohol intake, weight control, physical activity, and tobacco smoking.
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Affiliation(s)
- Motoki Iwasaki
- Epidemiology and Prevention Division, Research Center for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan.
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40
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Wu AH, Butler LM. Green tea and breast cancer. Mol Nutr Food Res 2011; 55:921-30. [PMID: 21538855 DOI: 10.1002/mnfr.201100006] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2011] [Revised: 02/16/2011] [Accepted: 03/01/2011] [Indexed: 01/22/2023]
Abstract
The identification of modifiable lifestyle factors that could reduce the risk of breast cancer is a research priority. Despite the enormous chemopreventive potential of green tea and compelling evidence from animal studies, its role in breast cancer development in humans is still unclear. Part of the uncertainty is related to the relatively small number of epidemiological studies on green tea and breast cancer and that the overall results from case-control studies and prospective cohort studies are discordant. In addition, the mechanisms by which green tea intake may influence risk of breast cancer in humans remain not well studied. We review the human studies that have evaluated the relationship between green tea intake and four biomarkers (sex steroid hormones, mammographic density, insulin-like growth factor, adiponectin) that are believed to be important in breast cancer development. Results from these biomarker studies are also inconclusive. Limitations of observational studies and areas of further investigations are discussed.
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Affiliation(s)
- Anna H Wu
- Department of Preventive Medicine, University of Southern California Keck School of Medicine, Los Angeles, CA, USA.
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Yu X, Bao Z, Zou J, Dong J. Coffee consumption and risk of cancers: a meta-analysis of cohort studies. BMC Cancer 2011; 11:96. [PMID: 21406107 PMCID: PMC3066123 DOI: 10.1186/1471-2407-11-96] [Citation(s) in RCA: 163] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Accepted: 03/15/2011] [Indexed: 12/24/2022] Open
Abstract
Background Coffee consumption has been shown to be associated with cancer of various sites in epidemiological studies. However, there is no comprehensive overview of the substantial body of epidemiologic evidence. Methods We searched MEDLINE, EMBASE, Science Citation Index Expanded and bibliographies of retrieved articles. Prospective cohort studies were included if they reported relative risks (RRs) and corresponding 95% confidence intervals (CIs) of various cancers with respect to frequency of coffee intake. We did random-effects meta-analyses and meta-regressions of study-specific incremental estimates to determine the risk of cancer associated with 1 cup/day increment of coffee consumption. Results 59 studies, consisting of 40 independent cohorts, met the inclusion criteria. Compared with individuals who did not or seldom drink coffee per day, the pooled RR of cancer was 0.87 (95% CI, 0.82-0.92) for regular coffee drinkers, 0.89 (0.84-0.93) for low to moderate coffee drinkers, and 0.82 (0.74-0.89) for high drinkers. Overall, an increase in consumption of 1 cup of coffee per day was associated with a 3% reduced risk of cancers (RR, 0.97; 95% CI, 0.96-0.98). In subgroup analyses, we noted that, coffee drinking was associated with a reduced risk of bladder, breast, buccal and pharyngeal, colorectal, endometrial, esophageal, hepatocellular, leukemic, pancreatic, and prostate cancers. Conclusions Findings from this meta-analysis suggest that coffee consumption may reduce the total cancer incidence and it also has an inverse association with some type of cancers.
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Affiliation(s)
- Xiaofeng Yu
- Department of Gastroenterology, Huadong Hospital, Fudan University, Shanghai 200040, PR China
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Yu X, Bao Z, Zou J, Dong J. Coffee consumption and risk of cancers: a meta-analysis of cohort studies. BMC Cancer 2011. [PMID: 21406107 DOI: 10.1186/1471-2407-11-96.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Coffee consumption has been shown to be associated with cancer of various sites in epidemiological studies. However, there is no comprehensive overview of the substantial body of epidemiologic evidence. METHODS We searched MEDLINE, EMBASE, Science Citation Index Expanded and bibliographies of retrieved articles. Prospective cohort studies were included if they reported relative risks (RRs) and corresponding 95% confidence intervals (CIs) of various cancers with respect to frequency of coffee intake. We did random-effects meta-analyses and meta-regressions of study-specific incremental estimates to determine the risk of cancer associated with 1 cup/day increment of coffee consumption. RESULTS 59 studies, consisting of 40 independent cohorts, met the inclusion criteria. Compared with individuals who did not or seldom drink coffee per day, the pooled RR of cancer was 0.87 (95% CI, 0.82-0.92) for regular coffee drinkers, 0.89 (0.84-0.93) for low to moderate coffee drinkers, and 0.82 (0.74-0.89) for high drinkers. Overall, an increase in consumption of 1 cup of coffee per day was associated with a 3% reduced risk of cancers (RR, 0.97; 95% CI, 0.96-0.98). In subgroup analyses, we noted that, coffee drinking was associated with a reduced risk of bladder, breast, buccal and pharyngeal, colorectal, endometrial, esophageal, hepatocellular, leukemic, pancreatic, and prostate cancers. CONCLUSIONS Findings from this meta-analysis suggest that coffee consumption may reduce the total cancer incidence and it also has an inverse association with some type of cancers.
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Affiliation(s)
- Xiaofeng Yu
- Department of Gastroenterology, Huadong Hospital, Fudan University, Shanghai 200040, PR China
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Iwasaki M, Inoue M, Sasazuki S, Sawada N, Yamaji T, Shimazu T, Willett WC, Tsugane S. Green tea drinking and subsequent risk of breast cancer in a population-based cohort of Japanese women. Breast Cancer Res 2010; 12:R88. [PMID: 22889409 PMCID: PMC3096981 DOI: 10.1186/bcr2756] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2010] [Accepted: 10/28/2010] [Indexed: 01/20/2023] Open
Abstract
Introduction Although many in vitro and animal studies have demonstrated a protective effect of green tea against breast cancer, findings from epidemiological studies have been inconsistent, and whether high green tea intake reduces the risk of breast cancer remains unclear. Methods In this Japan Public Health Center-based Prospective Study, 581 cases of breast cancer were newly diagnosed in 53,793 women during 13.6 years' follow-up from the baseline survey in 1990 to 1994. After the five-year follow-up survey in 1995 to 1998, 350 cases were newly diagnosed in 43,639 women during 9.5 years' follow-up. The baseline questionnaire assessed the frequency of total green tea drinking while the five-year follow-up questionnaire assessed that of two types of green tea, Sencha and Bancha/Genmaicha, separately. Results Compared with women who drank less than one cup of green tea per week, the adjusted hazard ratio (HR) for women who drank five or more cups per day was 1.12 (95% confidence interval (CI) 0.81 to 1.56; P for trend = 0.60) in the baseline data. Similarly, compared with women who drank less than one cup of Sencha or Bancha/Genmaicha per week, adjusted HRs for women who drank 10 or more cups per day were 1.02 (95% CI 0.55 to 1.89; P for trend = 0.48) for Sencha and 0.86 (0.34 to 2.17; P for trend = 0.66) for Bancha/Genmaicha. No inverse association was found regardless of hormone receptor-defined subtype or menopausal status. Conclusions In this population-based prospective cohort study in Japan we found no association between green tea drinking and risk of breast cancer.
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Affiliation(s)
- Motoki Iwasaki
- Epidemiology and Prevention Division, Research Center for Cancer Prevention and Screening, National Cancer Center, Chuo-ku, Tokyo, Japan.
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Plasma tea polyphenol levels and subsequent risk of breast cancer among Japanese women: a nested case–control study. Breast Cancer Res Treat 2010; 124:827-34. [DOI: 10.1007/s10549-010-0916-x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2010] [Accepted: 04/22/2010] [Indexed: 11/26/2022]
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45
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Is green tea drinking associated with a later onset of breast cancer? Ann Epidemiol 2010; 20:74-81. [PMID: 20006278 DOI: 10.1016/j.annepidem.2009.09.005] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Revised: 09/09/2009] [Accepted: 09/09/2009] [Indexed: 12/11/2022]
Abstract
BACKGROUND Studies have found that tea polyphenols inhibit aromatase. Because of the substantial difference in levels of estrogens between premenopausal and postmenopausal women, the relationship between tea consumption and breast cancer risk may depend on menopausal status. METHODS We examined this hypothesis in the Shanghai Women's Health Study, a population-based cohort study of 74,942 Chinese women. RESULTS We found a time-dependent interaction between green tea consumption and age of breast cancer onset (p for interaction, 0.03). In comparison with non-tea drinkers, women who started tea-drinking at 25 years of age or younger had a hazard ratio (HR) of 0.69 (95% confidence interval [CI]: 0.41-1.17) to develop premenopausal breast cancer. On the other hand, compared with non-tea drinkers, women who started tea drinking at 25 years of age or younger had an increased risk of postmenopausal breast cancer with an HR of 1.61 (95% CI: 1.18-2.20). Additional analyses suggest regularly drinking green tea may delay the onset of breast cancer. CONCLUSIONS Further studies are needed to confirm our findings.
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Inoue-Choi M, Yuan JM, Yang CS, Van Den Berg DJ, Lee MJ, Gao YT, Yu MC. Genetic Association Between the COMT Genotype and Urinary Levels of Tea Polyphenols and Their Metabolites among Daily Green Tea Drinkers. INTERNATIONAL JOURNAL OF MOLECULAR EPIDEMIOLOGY AND GENETICS 2010; 1:114-123. [PMID: 21191472 PMCID: PMC3010377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 12/10/2009] [Accepted: 02/20/2010] [Indexed: 05/30/2023]
Abstract
Available in vitro and animal studies have shown cancer protective effects of tea polyphenols. Recent study suggests a greater protective effect of green tea intake on breast cancer risk among women possessing the low-activity associated genotype of the catechol-O-methyltransferase (COMT), which may modulate the metabolism and excretion of tea polyphenols through urine. To determine the effect of COMT genotype on urinary excretion of tea polyphenol metabolites of daily green tea drinkers, a cross-sectional analysis was performed within the Shanghai Cohort Study, a population-based, prospective investigation of diet and cancer in 18,244men. In addition to an in-person interview, each participant provided a blood and urine sample at baseline. In the present study, COMT genotype (rs4680) and five urinary metabolites of tea polyphenols were determined in 660 cohort subjects who self-identified as daily drinkers of green tea. All urinary tea polyphenol measurements were expressed in units of urinary creatinine. Men possessing the homozygous low-activity associated COMT genotype (LL) exhibited statistically significantly lower urinary levels of individual as well as all of the five tea polyphenol metabolites under study relative to individuals possessing the wild type high-activity associated COMT genotype (HH)or the heterozygous variant genotype (HL). Levels of urinary tea polyphenol metabolites were comparable between men possessing the HH and HL genotypes. The present study demonstrated that men carrying low-activity associated COMT genotype excreted less tea polyphenols from urine, which suggests that they may retain more tea polyphenols in their bodies and derive greater health benefits from green tea intake.
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Affiliation(s)
- Maki Inoue-Choi
- Division of Epidemiology and Community Health, School of Public Health, University of Minnesota1300 S. Second St., WBOB Suite 300, Minneapolis, MN 55454, USA
| | - Jian-Min Yuan
- Division of Epidemiology and Community Health, School of Public Health, University of Minnesota1300 S. Second St., WBOB Suite 300, Minneapolis, MN 55454, USA
- The Masonic Cancer Center, University of MinnesotaMinneapolis, Minnesota, USA
| | - Chung S Yang
- Department of Chemical Biology, Rutgers UniversityPiscataway, New Jersey, USA
| | - David J Van Den Berg
- USC/Norris Comprehensive Cancer Center, University of Southern CaliforniaLos Angeles, California, USA
| | - Mao-Jung Lee
- Department of Chemical Biology, Rutgers UniversityPiscataway, New Jersey, USA
| | - Yu-Tang Gao
- Department of Epidemiology, Shanghai Cancer InstituteShanghai, People's Republic of China
| | - Mimi C Yu
- The Masonic Cancer Center, University of MinnesotaMinneapolis, Minnesota, USA
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Coffee and tea intake and risk of breast cancer. Breast Cancer Res Treat 2009; 121:461-7. [PMID: 19847643 DOI: 10.1007/s10549-009-0583-y] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2009] [Accepted: 10/07/2009] [Indexed: 10/20/2022]
Abstract
Known risk factors account for about 10-15% of breast cancer incidence suggesting that lifestyle exposures are crucial in its etiology. Previous epidemiological studies on the association between coffee and tea consumption and breast cancer risk have been inconsistent. We investigated the association of coffee and tea consumption with the risk of breast cancer among women in EPIC-NL cohort, a population-based prospective cohort in Netherlands with 27,323 participants. Exposure was measured by a validated food frequency questionnaire, and the outcome was verified by direct linkage with the Netherlands Cancer Registry. A total of 681 invasive primary breast cancers were diagnosed in 9.6 years of follow-up. Coffee intake increased the risk of breast cancer by more than twofold as compared to non-consumers (HR; 2.25, 95% CI; 1.30-3.90). This association did not hold after multivariate adjustment which resulted in a HR of 1.17, 95% CI; 0.65-2.12. After adjustment to breast cancer risk factors and lifestyle, no association was observed between intake of coffee or tea and risk of breast cancer across all categories of intake. These results were also not altered by body mass index (BMI). Coffee and tea consumption does not seem to be related to the risk of breast cancer in women.
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Naganuma T, Kuriyama S, Kakizaki M, Sone T, Nakaya N, Ohmori-Matsuda K, Hozawa A, Nishino Y, Tsuji I. Green tea consumption and hematologic malignancies in Japan: the Ohsaki study. Am J Epidemiol 2009; 170:730-8. [PMID: 19640889 DOI: 10.1093/aje/kwp187] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Several biologic studies have reported that green tea constituents have antitumor effects on hematologic malignancies. However, the effects in humans are uncertain. The authors used data from the Ohsaki National Health Insurance Cohort Study in Japan to evaluate the association between green tea consumption and the risk of hematologic malignancies. Study participants were 41,761 Japanese adults aged 40-79 years without a history of cancer at baseline who answered a food frequency questionnaire survey in 1994. During 9 years of follow-up beginning in 1995, the authors documented 157 hematologic malignancies, including 119 cases of lymphoid neoplasms and 36 cases of myeloid neoplasms. Hazard ratios were calculated by using the Cox proportional hazards regression model. Risk of hematologic malignancies was inversely associated with green tea consumption. The multivariate-adjusted hazard ratio of hematologic malignancies for 5 cups/day or more compared with less than 1 cup/day of green tea was 0.58 (95% confidence interval: 0.37, 0.89). The corresponding risk estimate was 0.52 (95% confidence interval: 0.31, 0.87) for lymphoid neoplasms and 0.76 (95% confidence interval: 0.32, 1.78) for myeloid neoplasms. This inverse association was consistent across sex and body mass index strata. In conclusion, green tea consumption was associated with a lower risk of hematologic malignancies.
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Affiliation(s)
- Toru Naganuma
- Division of Epidemiology, Department of Public Health and Forensic Medicine, Tohoku University School of Medicine, Miyagi, Japan.
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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: 108] [Impact Index Per Article: 7.2] [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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