ESTROGEN BIOTRANSFORMATIONS AND BREAST CANCER ETIOLOGY

据估计，60%-70%的人类乳腺癌与 性激素暴露。大约60%的乳腺癌患者 患者患有荷尔蒙依赖型乳腺癌，其中含有雌激素 受体，需要雌激素才能促进肿瘤生长。可能的 雌激素在乳腺癌发生发展中的生化作用 仍有待充分阐明。这项研究的重点是考试 类固醇激素和雌激素的生物转化在 乳腺癌病因学。我们的假设是， 乳腺癌组织微环境可影响乳腺癌的程度 雌激素的生物合成和代谢，导致水平的变化 荷尔蒙活性雌激素及其代谢物，因此 影响乳腺肿瘤的发展和生长。生化和 这一假说的体外分子检验将在#年进行。 人类患者乳腺组织标本和几种人类乳腺癌组织 我们实验室目前使用的细胞系统。这些乳腺细胞 系统包括永生化转化的乳腺上皮细胞培养 在塑料或细胞外基质载体(ECM等)上的单层中 Matrigel TM或I型胶原)和人乳腺基质细胞培养 从乳腺癌组织或正常乳腺组织中分离出来。 传统的塑料上细胞培养最大限度地促进了 在胶原蛋白或Matrigel载体上培养细胞时的增殖 细胞的维持和随后的分化。的具体目标 对人类各种乳腺细胞系统的研究主要有：(1)考察 芳香化酶(CYP19)和环氧合酶(COX-1和 COX-2)在乳腺癌标本中的表达，(2)检测 人乳腺组织中雌二醇酶的表达及其形成程度 癌细胞系统，(3)检查氧化形成的程度 人乳腺癌细胞系统中的代谢物，以及(4)测定 雌激素生物合成和代谢的生物学效应 人类乳房细胞系统。

An estimated 60-70 percent of human breast cancers are associated with sex hormone exposure. Approximately 60 percent of all breast cancer patients have hormone-dependent breast cancer, which contains estrogen receptors and requires estrogen for tumor growth. The possible biochemical roles of estrogens in the development of breast cancers remains to be fully elucidated. This research focuses on examination of the role of steroid hormones and estrogen biotransformations in breast cancer etiology. Our hypothesis is that alterations in the breast cancer tissue microenvironment can influence the extent of estrogen biosynthesis and metabolism, result in altered levels of hormonally active estrogens and their metabolites, and therefore influence breast tumor development and growth. Biochemical and molecular examination of this hypothesis in vitro will be performed in human patient breast tissue specimens and in several human breast cancer cell systems currently in use in our laboratories. These breast cell systems include immortalized transformed breast epithelial cells grown in monolayers on plastic or on extracellular matrix support (ecm such as Matrigel TM or collagen I) and cultures of human breast stromal cells isolated from breast cancer tissues or normal breast tissues. Traditional culturing of cells on plastic promotes maximal proliferation, while culturing cells on collagen or on Matrigel supports cell maintenance and subsequent differentiation. The specific aims of the research on the various human breast cell systems are (1) to examine the extent of aromatase (CYP19) expression and cyclooxygenase (COX-1 and COX-2) expression in human breast cancer specimens, (2) to examine enzyme expression and the extent of formation of E2 in human breast cancer cell systems, (3) to examine the extent of formation of oxidative metabolites in human breast cancer cell systems, and (4) to determine the biological consequences of estrogen biosyntesis and metabolism in the human breast cell systems.