Green Tea Extract - A powerful antioxidant and antimicrobial ingredient. Has the ability to penetrate the cell of the skin and protect the cell from free radicals and associated damage thus adding the antiaging benefit.
Green Tea - **A powerful antioxidant. Helps protect the cell from free radical damage.
Phase I study of green tea extract in patients with advanced lung cancer.
Laurie SA, Miller VA, Grant SC, Kris MG, Ng KK.
Thoracic Oncology Service, Division of Solid Tumor Oncology, Department of Medicine, Memorial Sloan-Kettering Cancer Center, Weill Medical College of Cornell University, 1275 York Avenue, 10126, New York, NY, USA.
PURPOSE. Epidemiologic studies suggest that consumption of green tea may have a protective effect against the development of several cancers. Preclinical studies of green tea and its polyphenolic components have demonstrated antimutagenic and anticarcinogenic activity, and inhibition of growth of tumor cell lines and animal tumor models, including lung cancer. Green tea may also have chemopreventive properties, and enhancement of cytotoxicity of chemotherapeutic agents has been demonstrated. This trial was designed to determine the maximum tolerated dose (MTD) of green tea extract (GTE) in patients with advanced lung cancer. METHODS. A total of 17 patients with advanced lung cancer were registered to receive once-daily oral dosing of GTE at a starting dose of 0.5 g/m(2) per day, with an accelerated dose-escalation scheme. RESULTS. On this schedule, the MTD of GTE was 3 g/m(2) per day, and at this dose, GTE was well tolerated with no grade 3 or 4 toxicity seen. Dose-limiting toxicities were diarrhea, nausea and hypertension. No objective responses were seen in this trial. Seven patients had stable disease ranging from 4 to 16 weeks; no patient remained on therapy longer than 16 weeks due to the development of progressive disease. CONCLUSIONS. This study suggests that while relatively nontoxic at a dose of 3 g/m(2) per day, GTE likely has limited activity as a cytotoxic agent, and further study of GTE as a single-agent in established malignancies may not be warranted. Further studies should focus on the potential chemopreventive and chemotherapy-enhancing properties of GTE.
Green tea consumption enhances survival of epithelial ovarian cancer patients.
Binns CW, Zhang M, Lee AH, Xie CX.
School of Public Health, Curtin University of Technology GPO Box U 1987, Perth 6845, Western Australia.
Aim: To investigate whether green tea consumption post-diagnosis can enhance survival of patients with epithelial ovarian cancer. Methods: A prospective cohort study was conducted in the community, Hangzhou, P. R. China. A cohort of 309 patients with histopathologically confirmed epithelial ovarian cancer, who were recruited in the study during 1999-2000, were followed for a minimum of three years. The variables measured included their survival time and the frequency and quantity of tea consumed post diagnosis. From the original cohort 294 (95.1%) subjects, or their close relatives, were traced and interviewed using a structured questionnaire in 2003. The actual number of deaths was obtained and the hazard ratios were calculated. Cox proportional models were used to compute adjusted hazard ratios (HR) and associated 95% confidence intervals (CI). These models were adjusted for age at diagnosis, locality, BMI, parity, stage at diagnosis, histo-pathologic grade of differentiation, cytology of ascites, and the presence of residual tumor after surgery. Results: Increasing frequency and quantity of tea consumption were associated a longer survival in Chinese women with epithelial ovarian cancer. The survival experiences were different between tea drinkers and non-drinkers (p <0.001). There were 109 (79.6%) out of 137 tea-drinkers who survived to the time of interview, compared with only 77 women (49.0%) still alive among the 157 non-tea drinkers. Compared with non-drinkers, the adjusted hazard ratios were 0.6 (95% CI 0.4-0.9) for tea-drinkers, 0.3 (95% CI 0.2-0.8) for consuming at least one cup of green tea per day, 0.4 (95%CI 0.2-0.8) for brewing at least one batch of green tea per day, and 0.3 (95% CI 0.2-0.8) for consumption of 500 grams or more dried tealeaf per year. The corresponding dose response relationships were statistically significant. Conclusion: Regular consumption of green tea post-diagnosis can enhance epithelial ovarian cancer survival. There are no previously published studies of ovarian cancer survival and tea consumption. This study has the potential to benefit many women who are diagnosed with ovarian cancer.
POLYPHENOL ANTIOXIDANTS IN GREEN TEA AND OATS:
POTENTIAL ROLES IN ANGIOGENESIS AND ATHEROSCLEROSIS
Mohsen Meydani, Liping Liu, Shaun Rodriguez
Vascular Biology Laboratory, Jean Mayer USDA-Human Nutrition Research Center on Aging at Tufts University, Boston, MA.
Cancer and cardiovascular diseases (CVD) are the major causes of morbidity and mortality among middle aged and older people in Western societies. Epidemiological and experimental evidence indicate that dietary habits play important roles in the risk of these diseases. Polyphenols with antioxidant capacity have recently been recognized for their potential health effects. Green tea contains catechins and oats are unique for their avenanthramides content; both are polyphenolics with powerful antioxidant capacity. Consumption of green tea, which is associated with a reduced risk of certain forms of cancer, can inhibit carcinogenesis and tumor growth and metastasis by suppressing angiogenesis. We have recently elucidated the molecular mechanism by which epigallocatechin gallate (EGCG), one of the green tea catechins, inhibits angiogenesis. EGCG inhibited tyrosine phosphorylation of vascular endothelial (VE)-cadherin in vascular endothelial cell growth factor (VEGF)-induced tube formation. In addition, EGCG inhibited the signaling pathway involving VEGFR, PI3-kinase, ?-catenin, and VE-cadherin complex. We have recently discovered that oats, in addition to their health benefits for CVD through their soluble fiber content, have potential anti-inflammatory and antiatherogenic properties due to their avenanthramides content. We have found that avenanthramides reduced expression of adhesion molecules such as ICAM-1, VCAM-1, and E-selectin, inhibited adhesion of monocytes to endothelial cells, and reduced expression of proinflammatory cytokines such as IL-6, IL-8, and MCP-1. Thus, inclusion of green tea and oats in the daily diet during a lifespan may reduce the risk of cancer and CVD, the two major age-related diseases. Supported by NCI grant# 1 R03CA94290-01 and USDA contract# 58-1950-9-001.