Mason Julie K, Thompson Lilian U
Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON M5S 3E2, Canada.
Appl Physiol Nutr Metab. 2014 Jun;39(6):663-78. doi: 10.1139/apnm-2013-0420. Epub 2013 Dec 23.
Flaxseed (FS), rich in the phytoestrogen lignans and α-linolenic acid-rich oil, has been suggested to have an anticancer effect. Questions remain whether FS and its lignan and oil components are effective in reducing breast cancer risk and tumour growth, and can interact beneficially with breast cancer drugs. To find answers, in vitro, animal, observational, and clinical studies on FS and its lignan and oil components were reviewed. The majority of studies in various rodent models show that 2.5%-10% FS diet or the equivalent amount of lignan or oil reduces tumour growth. Ten percent FS and equivalent lignans do not interfere with but rather increase the effectiveness of tamoxifen (80 mg/day) while the 4% FS oil increases trastuzumab/Herceptin (2.5 mg/kg) effectiveness. Observational studies show that FS and lignan intake, urinary excretion, or serum levels are associated with reduced risk, particularly in postmenopausal women. Lignans reduce breast cancer and all-cause mortality by 33%-70% and 40%-53%, respectively, without reducing tamoxifen effectiveness. Clinical trials show that FS (25 g/day with 50 mg lignans; 32 days) reduces tumour growth in breast cancer patients and lignans (50 mg/day; 1 year) reduces risk in premenopausal women. Mechanisms include decreased cell proliferation and angiogenesis and increased apoptosis through modulation of estrogen metabolism and estrogen receptor and growth factor receptor signalling pathways. More clinical trials are needed but current overall evidence indicates that FS and its components are effective in the risk reduction and treatment of breast cancer and safe for consumption by breast cancer patients.
富含植物雌激素木脂素和富含α-亚麻酸的油的亚麻籽（FS），已被认为具有抗癌作用。FS及其木脂素和油成分是否能有效降低乳腺癌风险和肿瘤生长，以及能否与乳腺癌药物产生有益的相互作用，仍存在疑问。为了找到答案，我们对关于FS及其木脂素和油成分的体外、动物、观察性和临床研究进行了综述。各种啮齿动物模型中的大多数研究表明，2.5%-10%的FS饮食或等量的木脂素或油可减少肿瘤生长。10%的FS和等量的木脂素不会干扰他莫昔芬（80毫克/天）的疗效，反而会增强其效果，而4%的FS油可提高曲妥珠单抗/赫赛汀（2.5毫克/千克）的疗效。观察性研究表明，FS和木脂素的摄入量、尿排泄量或血清水平与风险降低相关，尤其是在绝经后女性中。木脂素可分别将乳腺癌和全因死亡率降低33%-70%和40%-53%，且不会降低他莫昔芬的疗效。临床试验表明，FS（25克/天，含50毫克木脂素；32天）可减少乳腺癌患者的肿瘤生长，木脂素（50毫克/天；1年）可降低绝经前女性的风险。其机制包括通过调节雌激素代谢、雌激素受体和生长因子受体信号通路来减少细胞增殖和血管生成，并增加细胞凋亡。还需要更多的临床试验，但目前的总体证据表明，FS及其成分在降低乳腺癌风险和治疗方面是有效的，并且乳腺癌患者食用是安全的。
