Polyphenols in green tea and apples block the activity of VEGF, a protein involved in the formation of blood vessels. This process is involved in the development of atherosclerotic plaques and the progression of cancer.
Vascular endothelial growth factor (VEGF) is a protein that is involved in the signaling pathway that results in angiogenesis (the formation of blood vessels). Angiogenesis is an important process in the progression of cancer, in addition to the formation of atherosclerotic plaques. Several currently available drugs are targeted at inhibiting the activity of VEGF, including: bevacizumab, sorafenib and sunitinib.
A study conducted at the Institute of Food Research, Norwich Research Park, Norwich, UK, has shown that polyphenols present in green tea (EGCG) and apples (procyanidins) can inhibit the activation of VEGF-2 signaling via VEGF. The polyphenols interact directly with the VEGF protein, resulting in its inactivation so that it can no longer bind to its receptor, VEGFR-2. This results in an overall reduction in angiogenesis. Most importantly, the study demonstrated that these effects are seen at concentrations of polyphenols that are achievable in the blood stream following consumption of polyphenol-containing foods. Since this study was conducted using human umbilical vein endothelial cells, future research should be aimed at providing clinical evidence for a reduction of VEGF signaling following consumption of polyphenol-rich foods or supplements.
A clinical trial currently recruiting participants, will assess green tea extract containing polyphenols in patients with prostate cancer. The study will investigate the effect on preventing or slowing cancer growth. The researchers will measure various biomarkers of tumor growth and progression, in addition to levels of VEGF. This study is being conducted at Case Medical Center, University Hospitals Seidman Cancer Center, Case Comprehensive Cancer Centre, Cleveland, Ohio, United States, in collaboration with the National Cancer Institute. It will include patients aged between 45-85 years, who have low-grade and low-volume prostate cancer that has been diagnosed in the previous year.
Moyle, CWA, Cerezo, AB, Winterbone, MS, Hollands, WJ, Alexeev, Y, Needs, PW, Kroon, PA. “Potent inhibition of VEGFR-2 activation by tight binding of green tea epigallocatechin gallate and apple procyanidins to VEGF: Relevance to angiogenesis” Molecular Nutrition & Food Research Volume 59, Issue 3, pages 401–412, March 2015. DOI: 10.1002/mnfr.201400478
clinicaltrials.gov “Green Tea Extract in Treating Patients With Low-Risk Prostate Cancer” Available From: https://www.clinicaltrials.gov/ct2/show/NCT01928485?term=green+tea+AND+VEGF&rank=2 Last Accessed April 16, 2015.
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