A premalignant chronology of cell-state variability in basal-like breast cancer

在受资助的父母赠款1R01CA256199-01A1中，标题为《癌变前细胞状态变异年表》 ，我们建议对基因表达谱进行全面、渐进的分析 基底细胞样乳腺癌癌前阶段突变细胞的研究 可能会导致肿瘤的发展。基底细胞样癌是一种进展迅速且高度可变的肿瘤亚型。 自发发生的乳腺癌(通常发生在非裔美国人中)或遗传易感性的女性。 这种肿瘤被认为是由于BRCA1和TP53肿瘤抑制基因的功能丧失引起的 未固定的乳房基底腔祖细胞。然而，剖析其起源一直具有挑战性。 这种疾病缺乏适当的工具，这使得很难想象细胞状态的变异性是如何 癌前突变会导致基底细胞样乳腺癌。当前的应用程序在基因上部署了一种新的 被称为双标记镶嵌分析(MADM)的工程化小鼠模型，它随机删除小鼠 BRCA1-TrP53在乳腺转运扩增祖细胞中的表达。在MADM中，随机删除是 基因上由GFP的共表达定义，允许局部扩大的癌前病变可视化 在基底细胞样病发病前，在腺体内。亲本R01的目的是使用转录 分析：1)确定BRCA1引发的基底膜多样化的共同癌前轨迹- 小鼠和人类的TP53缺乏症。2)去卷积局部配对的免疫异质性 基底细胞样乳腺癌的特定癌前生态系统。3)从功能上验证单元格状态的重要性 通过使用遗传的、药理学的和旁分泌的扰动，使内在或 体外研究癌前细胞的外在变异性。Jan和Zong是他们各自的思想领袖 肿瘤内细胞状态异质性的领域和多年追踪的基因工程小鼠模型 协作记录。与两位资深临床医生一起，该团队将有一个重要的整体 对我们理解基底样乳腺肿瘤发生的影响。副刊提出的项目 候选与父R01中提出的实验截然不同，但完全互补：虽然 父母R01专注于基于基因表达谱描绘细胞状态可塑性，她的项目 从表型导向的功能干预中探讨这一问题。在具体目标1中，她计划 研究异常激素信号在癌前进展和检测潜力中的作用 治疗策略。在特定目标2中，她将调查癌前过度增殖是否可以 利用PARPI处理进行开发。作为一个整体，这些互补的实验不仅应该允许我们 更深入地研究基底细胞样乳腺癌癌前进展的关键机制，但也 为补充候选人提供优秀的培训经验，包括板凳技能、批判性思维、 科学交流，与基础和临床研究人员建立网络，以及领导技能。

In the funded parent grant 1R01 CA256199-01A1 entitled “premalignant chronology of cell-state variability in basal-like breast cancer”, we proposed to comprehensively and progressively analyze gene expression profiles of mutant cells during the premalignant stage of basal-like breast cancer to understand how cell state plasticity could lead to tumor progression. Basal-like carcinoma is a rapidly-progressing and highly variable subtype of breast cancer that arises spontaneously (often in African Americans) or in genetically predisposed women. Such tumors are believed to arise from the functional loss of the BRCA1 and TP53 tumor suppressors in uncommitted basoluminal progenitors of the breast. However, it has been challenging to dissect the origins of the disease for lack of appropriate tools, making it difficult to conceive of how the cell-state variability of premalignant mutants gives rise to basal-like breast cancer. The current application deploys a novel genetically engineered mouse model called mosaic analysis of double markers (MADM), which randomly deletes murine Brca1–Trp53 in transit-amplifying progenitors of the mammary gland. In MADM, stochastic deletion is genetically defined by coexpression of GFP, allowing locally expanded premalignant lesions to be visualized within the gland before the onset of basal-like disease. The aims of the parent R01 are to use transcriptomic analysis: 1) To define shared premalignant trajectories of basoluminal diversification triggered by BRCA1– TP53 deficiency in mice and humans. 2) To deconvolve the immune heterogeneities that are locally paired with specific premalignant ecosystems for basal-like breast cancer. 3) To functionally validate cell states important for progression by using genetic, pharmacologic, and paracrine perturbations that homogenize intrinsic or extrinsic variability of premalignant cells ex vivo. Co-PIs Janes and Zong are thought leaders in their respective fields of intratumor cell-state heterogeneity and genetically engineered mouse modeling with a multi-year track record of collaboration. Together with a pair of senior clinicians, the team is poised to have a significant overall impact on our understanding of basal-like breast tumorigenesis. The project proposed by the supplement candidate is distinct from but perfectly complements with the experiments proposed in the parent R01: while the parent R01 focuses on delineating cell state plasticity based on gene expression profiles, her project approaches the problem from phenotype-guided functional interventions. In Specific Aim 1, she plans to investigate the involvement of aberrant hormonal signaling during premalignant progression and test potential treatment strategies. In Specific Aim 2, she will investigate whether premalignant hyperproliferation can be exploited using PARPi treatment. As a whole, these complementary experiments should not only allow us to dive more deeply into key mechanisms of premalignant progression of basal-like breast cancer, but also provide excellent training experience for the supplement candidate, including bench skills, critical thinking, scientific communication, networking with both basic and clinical researchers, and leadership skills.