Development in a dish: an ex-vivo fetal mammary assay for toxicological research

培养皿中的发育：用于毒理学研究的离体胎儿乳腺测定

• 批准号: 10005424
• 负责人: ANA SOTO
• 金额: $ 20.63万
• 依托单位: TUFTS UNIVERSITY BOSTON
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2022-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10005424
• 关键词: Adoption; Adult; Affect; Age-Months; Animal Model; Animals; Area; Behavior; Biological Assay; Bypass; Chemical Actions; Chemicals; Complex; Data; Data Reporting; Development; Developmental Toxicant; Diethylstilbestrol; Disease; Dose; Duct (organ) structure; Endocrine; Endocrine Disruptors; Estrogens; Ethinyl Estradiol; European; Evaluation; Exposure to; Fetal Development; Gland; Goals; Growth; Health; Hormonal; Hormones; Human; Hyperplasia; Impairment; In Vitro; Incidence; Infertility; Intraductal Hyperplasia; Lactation; Length; Lesion; Life; Link; Malignant Neoplasms; Mammary Neoplasms; Mammary gland; Measurement; Measures; Metabolic Diseases; Methods; Modeling; Morphogenesis; Morphology; National Toxicology Program; Neonatal; Neoplasms; Obesity; Organogenesis; Outcome; Pathology; Perinatal Exposure; Phenotype; Physiological; Population; Preventive; Process; Quantitative Evaluations; Regulation; Reporter Genes; Reproducibility; Reproduction; Research; Risk; Rodent; Steroidal Estrogen; System; Testing; Time; Toxicology; Validation; Woman; Work; bisphenol A; developmental toxicity; exposed human population; fetal; hypothalamic pituitary ovarian axis; in vivo; malignant breast neoplasm; mammary gland development; neoplastic; nonhuman primate; postnatal; prenatal exposure; response; screening; tool; toxicant; xenoestrogen

Summary More than 80,000 chemicals are registered for commercial use in the U.S. Many of them are endocrine disruptors and pose major risks to human health, hence the need for efficient evaluation of their developmental toxicity. Fetal organogenesis is a period of increased vulnerability to toxicants, in particular to those that interfere with hormone action. The fetal mammary gland is considered particularly vulnerable to hormonal disruption; exposure to xenoestrogens like diethylstilbestrol (DES) increased breast cancer incidence in women. Despite this finding, there is no data reporting the effects of DES during fetal MG development (to be examined in S. Aim 1). Likewise, fetal exposure to bisphenol A (BPA) and its replacements led to the development of pre- neoplastic and neoplastic lesions that manifested postnatally, long after the end of exposure (effect on fetal MG development will be examined in S. Aim 2). There is currently no reproducible system that allows for the observation of the direct effects of hormones and endocrine disruptors on the developing mammary gland while bypassing the effect of endogenous hormones and the estrogen-trapping effect of alphafetoprotein (AFP). Using an ex-vivo culture assay in which the mammary bud completes fetal morphogenesis in-vitro, allowed us to observe this process in real time. Validation of the ex-vivo method requires comparing the effects of selected chemicals that do not bind to AFP in the ex-vivo and in-vivo assays. In this regard, we observed that ethinyl estradiol, a steroidal estrogen that does not bind to AFP inhibited ductal growth both ex-vivo and in-vivo. In contrast, low BPA concentrations increased ductal development both in-vivo and in this ex-vivo explant method. Aim 1: To examine the ex-vivo and in-vivo effects of DES on fetal mammary gland development. Aim 2: To compare the ex-vivo and in-vivo fetal MG phenotype caused by exposure to endocrine disruptors known to induce proliferative lesions and/or cancer in rodents. We will use the BPA replacements BPS and BPAF. A validated ex-vivo culture assay of the developing MG will greatly facilitate mechanistic and morphometric studies of mammary gland development and provide toxicologists with a reliable, faster method to test chemicals for potential developmental toxicity.

总结 超过80，000种化学品在美国注册用于商业用途，其中许多 是内分泌干扰物，对人类健康构成重大风险，因此需要 有效评价其发育毒性。胎儿器官形成是一个 增加对有毒物质的脆弱性，特别是那些干扰激素的物质 行动上胎儿乳腺被认为是特别容易受到激素的影响， 破坏;暴露于异种雌激素如己烯雌酚（DES）增加乳腺癌 女性癌症发病率。尽管有这一发现，没有数据报告的影响， DES在胎儿MG发育过程中的作用（在S.目标1）。同样，胎儿 暴露于双酚A（BPA）及其替代品导致了前 肿瘤和肿瘤性病变，表现在出生后，结束后很久， 暴露（对胎儿MG发育的影响将在S.目标2）。 目前还没有一个可重复的系统，允许观察的直接 激素和内分泌干扰物对乳腺发育的影响， 绕过内源性激素的作用和雌激素的捕获作用， 甲胎蛋白（AFP）。使用离体培养测定，其中乳腺芽 在体外完成胎儿形态发生，使我们能够真实的观察这个过程。 离体方法的验证需要比较所选化学品的效果 其在离体和体内测定中不结合AFP。在这方面，我们观察到， 炔雌醇，一种不与AFP结合的类固醇雌激素， 离体和体内生长。相比之下，低BPA浓度增加了导管 在体内和这种离体外植体方法中的发育。 目的1：研究DES对胎儿乳腺的影响 发展目的2：比较体外和体内胎儿MG表型， 暴露于内分泌干扰物，已知可诱导增殖性病变和/或癌症， 啮齿动物我们将使用BPA替代BPS和BPAF。经验证的离体培养 对发育中MG的分析将极大地促进机理和形态学研究 为毒理学家提供了一种可靠、快速的方法 测试化学物质对发育的潜在毒性