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.

概括 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 有效评估其发育毒性。胎儿器官发生是一个时期 更容易受到有毒物质的侵害，特别是那些干扰激素的物质 行动。胎儿乳腺被认为特别容易受到荷尔蒙的影响 破坏；接触己烯雌酚 (DES) 等异雌激素会导致乳房增大 女性癌症发病率。尽管有这一发现，但没有数据报告其影响 胎儿 MG 发育期间的 DES（将在 S. 目标 1 中进行检查）。同样，胎儿 接触双酚 A (BPA) 及其替代品导致了预 出生后很久才出现的肿瘤和肿瘤性病变 暴露（对胎儿 MG 发育的影响将在 S. 目标 2 中进行检查）。 目前还没有可重复的系统可以直接观察 激素和内分泌干扰物对发育中的乳腺的影响 绕过内源性激素的作用和雌激素捕获作用 甲胎蛋白（AFP）。使用离体培养测定法，其中乳芽 在体外完成胎儿形态发生，使我们能够实时观察这一过程。 体外方法的验证需要比较所选化学品的效果 在离体和体内测定中不与 AFP 结合。对此，我们观察到 乙炔雌二醇是一种类固醇雌激素，不与 AFP 结合，抑制导管 离体和体内生长。相反，低 BPA 浓度会增加导管 体内和体外外植体方法的开发。 目标 1：检查 DES 对胎儿乳腺的体外和体内影响 发展。目标 2：比较由以下原因引起的离体和体内胎儿 MG 表型 接触已知会诱发增殖性病变和/或癌症的内分泌干扰物 啮齿动物。我们将使用 BPA 替代 BPS 和 BPAF。经过验证的离体培养物 发育中的 MG 测定将极大地促进机械和形态测量研究 乳腺发育，并为毒理学家提供可靠、更快的方法 测试化学品的潜在发育毒性。