Next Generation Rat Models of ER+ Breast Cancer

下一代ER+乳腺癌大鼠模型 翻译后摘要：尽管雌激素受体阳性（ER+）乳腺癌（BCa）的患病率，没有 具有免疫活性并自发转移至临床相关器官的哺乳动物模型 例如骨头。ER+ BCs占BCa病例的约70%，可通过手术切除和辅助治疗进行治疗 内分泌疗法虽然5年生存率很高，但转移复发的风险持续到12月。 20-40%的ER+ BCa患者最终死于转移性疾病，最常见于骨中。我们 ER+ BCa的有限知识主要来源于过度简化的细胞系模型和体外研究， 实验我们现有的异种移植模型排除了关键的免疫成分， 工程小鼠模型（GEMM）很少稳定地维持ER表达并依赖于ER信号传导， 没有转移到骨，最常见的部位。因此，对最初的肿瘤知之甚少- ER+ BCa的发生过程和骨转移，这极大地阻碍了我们开发新的预防措施的努力。 可以阻断/治疗ER+ BCa骨转移的策略或辅助疗法。我们已经开发出一种 通过导管内注射病毒引入遗传改变的一系列大鼠ER+ BCa模型。我们 初步数据表明这些大鼠ER+乳腺肿瘤：1）在免疫活性宿主中发生， 2)表现出内分泌治疗敏感性或耐药性，3）易形成ER+转移，包括骨转移 - 所有这些都是现有BCa模型中缺乏的关键特性。基于这些，我们假设， 基于大鼠的乳腺癌导管内注射模型（RIIM）忠实地再现了人类ER+ BCa， 在肿瘤发生、转移和治疗反应方面。我们会致力达致以下三个目标：（1） 表征RIIM模型中ER+ BCa的早期进展。(2)为了表征转移行为， RIIM模型中的ER+ BCa。(3)验证ER+ RIIM模型在重现治疗反应中的作用， 人ER+ BCa的耐药机制。

Title: Next Generation Rat Models of ER+ Breast Cancer Abstract: Despite the prevalence of estrogen receptor-positive (ER+) breast cancer (BCa), there are no mammalian models that are immunocompetent and metastasize spontaneously to clinically relevant organs such as bones. ER+ BCs comprise ~70% of BCa cases and are treated with surgical resection and adjuvant endocrine therapies. Although the 5-year survival rate is high, risk of metastatic recurrence persists for dec- ades, and 20-40% of ER+ BCa patients eventually succumb to metastatic disease, most often in bones. Our limited knowledge of ER+ BCa has been largely derived from oversimplified cell line models and in vitro experiments. Our available xenograft models exclude the critical immune component while genetically engineered mouse models (GEMMs) rarely stably maintain ER expression and rely on ER signaling – and none metastasize to bone, the most frequent site. As a result, very little is known about the initial tumori- genesis process and bone metastasis of ER+ BCa, which greatly impedes our effort to develop new prevention strategies or adjuvant therapeutics that can block/treat ER+ BCa bone metastasis. We have developed a series of rat ER+ BCa models by intraductal injection of viruses to introduce genetic alterations. Our preliminary data demonstrated that these rat ER+ mammary tumors: 1) developed in immunocompetent hosts, 2) showed endocrine therapy sensitivity or resistance, and 3) readily formed ER+ metastases including in bone – all of which are key properties that are lacking in existing BCa models. Based on these, we hypothesize that rat-based intraductal injection models (RIIMs) of breast cancer faithfully recapitulate human ER+ BCa in terms of tumor initiation, metastasis, and therapeutic responses. We will pursue the following three aims: (1) To characterize early progression of ER+ BCa in RIIM models. (2) To characterize the metastatic behaviors of ER+ BCa in RIIM models. (3) To credential ER+ RIIM models in recapitulating therapeutic responses and resistance mechanisms of human ER+ BCa.