Folkerd Elizabeth J, Martin Lesley-Ann, Kendall Anne, Dowsett Mitch
Academic Department of Biochemistry, Royal Marsden Hospital, Fulham Road, London SW3 6JJ, UK.
J Steroid Biochem Mol Biol. 2006 Dec;102(1-5):250-5. doi: 10.1016/j.jsbmb.2006.09.024. Epub 2006 Oct 17.
Breast cancer accounts for 1 in 4 of all female cancers worldwide; approaching 13,000 women dying per year in the UK alone. Seventy five per cent of all diagnosed breast cancers are oestrogen receptor (ER) positive. Ovarian synthesis of oestrogens ceases at menopause and as breast cancer is more prevalent in postmenopausal women the non-ovarian sources of oestrogen are important in disease progression. There is now considerable evidence that associates increased breast cancer risk with prolonged exposure to oestrogens hence greater attention is now being given to determining whether the measurement of plasma oestrogen may assist in identifying chemoprevention target groups. Studies suggest that in most postmenopausal patients the intra-tumoural concentrations of oestrogens are up to 20-fold higher than those present in the plasma however, while the extent of biosynthesis of oestrogens within breast tissue is a major determinant of local exposure, plasma levels are a useful indicator of overall metabolism in peripheral tissues. As such it is important to understand factors that influence these measurements. This review summarises the impact of lifestyle such as body mass index, together with the role of genetic polymorphisms placed within the context of designing future epidemiological studies and breast cancer risk algorithms.
乳腺癌占全球所有女性癌症的四分之一；仅在英国，每年就有近13000名女性死于乳腺癌。所有已确诊的乳腺癌中，75%是雌激素受体（ER）阳性。雌激素的卵巢合成在绝经时停止，由于乳腺癌在绝经后女性中更为普遍，雌激素的非卵巢来源在疾病进展中很重要。现在有大量证据表明，长期接触雌激素会增加患乳腺癌的风险，因此现在人们更加关注血浆雌激素的测量是否有助于识别化学预防目标群体。研究表明，在大多数绝经后患者中，肿瘤内雌激素浓度比血浆中高出20倍，然而，虽然乳腺组织内雌激素的生物合成程度是局部暴露的主要决定因素，但血浆水平是外周组织整体代谢的有用指标。因此，了解影响这些测量的因素很重要。本综述总结了体重指数等生活方式的影响，以及基因多态性在设计未来流行病学研究和乳腺癌风险算法中的作用。
