Endocrine Status of MG Stroma Alters Breast CA Invasion

MG 基质的内分泌状态改变乳腺 CA 侵袭

• 批准号: 6752376
• 负责人: Pepper J Schedin
• 金额: $ 20.79万
• 依托单位: AMC CANCER RESEARCH CENTER
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-06-04 至 2005-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6752376
• 关键词: RNase protection assay; actins; athymic mouse; bone neoplasms; brain neoplasms; breast neoplasms; cadherins; connective tissue stroma; differential display technique; enzyme induction /repression; gelsolin; immunocytochemistry; laboratory rat; liver neoplasms; lung neoplasms; metalloendopeptidases; metastasis; neoplasm /cancer invasiveness; polymerase chain reaction; pregnancy; vimentin

DESCRIPTION (provided by applicant): The relationship between reproductive history and breast cancer is complex. A full term pregnancy in younger women is protective against breast cancer later in life, while a first full term pregnancy after 40 years of age is associated with higher cancer occurrence. In addition, there is an increase in breast cancer within the first two years of pregnancy, regardless of age. Pregnancy associated breast cancer also presents at a later clinical stage and is more invasive than non-pregnancy associated breast cancers. We hypothesize that the cancer promotional effect of pregnancy is due to physiologic remodeling of the mammary stroma that occurs after pregnancy. During parturition or weaning-induced mammary gland involution, mammary stroma is degraded and stroma levels of matrix metalloproteinases (MMP) and pro-inflammatory mediators are elevated. We propose that these involution-associated changes in mammary stroma promote an epithelial to mesenchymal transition (EMT) in pre-existing neoplastic cells. The resulting activated tumor cells, coupled with the weakened stromal barrier, increases the likelihood of tumor cell extravasation. Since the likelihood of having occult tumor cells increases with age, pregnancy associated gland involution is more likely to effect EMT and metastases in older women. In Aim 1. the hypothesis that tumor cell metastatic potential is modulated by reproductive status will be tested in vivo using xenograft models. Human mammary tumor cells will be injected directly into teats or mammary fat pads of immunodeficient mice at different reproductive stages (i.e. nulliparous, 'pregnancy-associated', and parous). The ability of tumor cells to exit the gland is predicted to be dependent on the degree of tissue remodeling at the time of injection: low in nulliparous and parous, and high in regressing glands. Primary tumors will be evaluated histologically and metastases to lung, liver, brain and long bone of the leg will be measured by semi-quantitative PCR using a unique human sequence, the CCR5 gene. In Aim 2, the hypothesis that endocrine-induced changes in stroma composition can either promote or suppress EMT will be evaluated in vitro using reconstitution models. Human mammary epithelial cells, which differ in metastatic potential from non-tumorigenic to metastatic, will be combined with mammary stroma isolated from rats with different reproductive states. It is anticipated that quiescent mammary stroma (nulliparous and parous) will inhibit, while involuting matrix will promote EMT in highly metastatic cells. Functional evidence for EMT will be obtained by measuring stroma-dependent changes in cell adhesion, motility and invasiveness using modified Boyden chambers assays. Morphological and biochemical evidence for EMT will be evaluated in a 3-dimensional model of tumor formation. The effects of mammary matrix on key markers of EMT, actin fiber organization, and expression of E-cadherin, vimentin, gelsolin and Fspl proteins, will be determined biochemically. In Aim 3, the hypothesis that involuting mammary matrix induces, while nulliparous and parous mammary matrices suppress expression of MMP in tumor cells will be evaluated by reporter gene assays. Luciferase-based reporter constructs containing either the stromelysin (MMP-3), gelatinase A (MMP-2), or gelatinase B (MMP-9) promoters will be tested for activity in tumor cells plated on different mammary matrices. The results of these studies will contribute to our understanding of the effects pregnancy-associated changes in mammary stroma have on breast cancer progression, and should provide insights into epidemiological data describing the dual effect of pregnancy on breast cancer.

描述（由申请人提供）：生殖 乳腺癌的病因很复杂。年轻女性的足月妊娠 预防乳腺癌在以后的生活中，而第一个完整的任期， 40岁以后怀孕与癌症发生率较高有关。在 此外，乳腺癌的发病率在2008年的头两年有所增加。 怀孕，不论年龄。妊娠相关性乳腺癌也会出现 在较晚的临床阶段，比非妊娠相关的更具侵袭性 乳腺癌我们假设怀孕对癌症的促进作用 是由于乳腺基质的生理性重塑， 怀孕在分娩或断奶引起的乳腺退化期间， 乳腺基质降解，基质金属蛋白酶（MMP） 促炎介质升高我们建议，这些 退化相关的乳腺间质变化促进上皮细胞 间充质转化（EMT）在预先存在的肿瘤细胞。所得 激活的肿瘤细胞，加上减弱的基质屏障，增加了肿瘤细胞的增殖。 肿瘤细胞外渗的可能性。因为神秘的可能性 肿瘤细胞随年龄增长而增多，妊娠相关腺体退化较多 可能影响老年妇女的EMT和转移。在目标1中。的假设 肿瘤细胞的转移潜能受生殖状态的调节， 使用异种移植模型在体内进行测试。人类乳腺肿瘤细胞将被 直接注射到免疫缺陷小鼠的乳头或乳房脂肪垫中， 不同的生殖阶段（即未经产、“妊娠相关”和 经产）。预测肿瘤细胞离开腺体的能力是 取决于注射时组织重塑的程度： 未经产和经产的，并且在退化的腺体中高。原发性肿瘤将 组织学评估和肺，肝，脑和长骨的转移， 腿将通过半定量PCR使用独特的人 CCR 5基因。在目标2中，假设内分泌诱导 基质成分的变化可以促进或抑制EMT， 使用重建模型进行体外评价。人乳腺上皮细胞， 从非致瘤性到转移性的转移潜能不同， 与从不同生殖器官的大鼠中分离的乳腺基质结合 states.预期静止乳腺基质（未经产和 对合基质能促进EMT， 转移细胞EMT的功能证据将通过测量 细胞粘附、运动和侵袭性的基质依赖性变化 改良Boyden小室法。EMT的形态学和生化证据 将在肿瘤形成的三维模型中进行评估。的影响 乳腺基质对EMT、肌动蛋白纤维组织和表达的关键标志物的影响 将测定E-钙粘蛋白、波形蛋白、凝溶胶蛋白和Fspl蛋白的含量 生物化学在目的3中，假设退化的乳腺基质诱导， 而未经产和经产的乳腺基质抑制MMP的表达， 肿瘤细胞将通过报道基因测定进行评价。基于荧光素酶 含有基质分解素（MMP-3）、明胶酶A 将测试明胶酶B（MMP-9）启动子在肿瘤中的活性。 细胞接种在不同的乳腺基质上。这些研究的结果将 有助于我们理解妊娠相关变化对 乳腺间质对乳腺癌进展的影响， 描述怀孕对乳房的双重影响的流行病学数据 癌