美国路易斯安那州立大学研究人员6月19日公布研究报告说，绿茶中所含的多酚类活性成分EGCG或许可以减缓前列腺癌的生长。
研究人员在美国新一期《癌症预防研究》（Cancer Prevention Research）杂志上报告说，他们对26名年龄在41岁至72岁之间的前列腺癌患者进行了测试。
这些患者每天服用4粒富含EGCG的胶囊，并在进行前列腺切除手术的当天停止用药。他们的服药期从12天至73天不等，平均为34．5天。
研究人员发现，这些患者血清中用来衡量前列腺癌生长的3种标记物的水平都有所下降，其中肝细胞生长因子水平平均下降18．9％，血管内皮生长因子水平下降9．9％，前列腺特异抗原水平平均下降10．4％。一些患者血清内的肝细胞生长因子和血管内皮生长因子水平甚至下降了30％以上。这些患者基本没有出现不良反应，肝功能也都正常。
领导这项研究的路易斯安那州立大学保健学中心教授詹姆斯·卡德利表示，绿茶中的活性成分能限制癌细胞快速生长，但不一定能将肿瘤缩小。不过，绿茶确实可以作为化疗和放疗的有益补充。卡德利还表示，他们的研究只是小型测试，相关成果还需要大型研究加以确认。
美国癌症协会提供的数据显示，前列腺癌目前是美国男性的第二大癌症死因。该协会预计，2009年，美国死于前列腺癌的男性将达到2．7万人，新增病例将达到19．2万例。（生物谷Bioon.com）
生物谷推荐原始出处：
Cancer Prevention Research 2, 531, June 1, 2009. doi: 10.1158/1940-6207.CAPR-08-0185
Lung Cancer Inhibitory Effect of Epigallocatechin-3-Gallate Is Dependent on Its Presence in a Complex Mixture (Polyphenon E)
Huijing Fu1, Jun He2, Fan Mei1, Qi Zhang2, Yukihiko Hara3, Seto Ryota2, Ronald A. Lubet4, Ruth Chen1, Da-Ren Chen1 and Ming You2,3
Authors' Affiliations: 1 Department of Energy, Environmental and Chemical Engineering, Washington University of St. Louis and 2 Department of Surgery, Campus Box, The Alvin J Siteman Cancer Center, Washington University School of Medicine, St. Louis, Missouri; 3 Mitsui Norin Co., Ltd., Shizuoka, Japan; and 4 Chemoprevention Agent Development Research Group, National Cancer Institute, Bethesda, Maryland
Green tea has been shown to exhibit cancer-preventive activities in preclinical studies. However, (–)-epigallocatechin-3-gallate (EGCG) alone was shown to be ineffective in preventing lung tumorigenesis in mice by aerosol administration. In this study, Polyphenon E and Polyphenon E without EGCG were administered by aerosol delivery to A/J mice 2 weeks after carcinogen treatment and continuing daily throughout the remainder of the study (20 weeks). An improved aerosol delivery system with a custom-built atomizer, an efficient solvent remove system, and a nose-only exposure chamber was used to provide aerosols with stable size distribution. There were no significant differences in the size distributions of Polyphenon E and Polyphenon E without EGCG. With a relatively low dose level (4.19 mg/kg), Polyphenon E decreased tumor multiplicity by 53%, whereas Polyphenon E without EGCG at the same dose failed to inhibit lung carcinogenesis. These results indicate that aerosol administration can be an effective approach in chemoprevention study, and aerosolized Polyphenon E can significantly inhibit pulmonary adenoma formation and growth in A/J mice. Furthermore, in aerosolized form, EGCG, which is thought to be the most active component of Polyphenon E, has to be present with other tea catechins to show chemopreventive activity on lung tumorigenesis.
