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

项目摘要/摘要 基底细胞样癌是一种进展迅速、变异性高的乳腺癌亚型。 自发的(通常是非裔美国人)或遗传易感的女性。这种肿瘤被认为是 肿瘤抑制基因BRCA1和TP53在未受控的基底膜中的功能丧失 乳房的祖先。然而，由于缺乏证据，剖析这种疾病的起源一直具有挑战性。 合适的工具，这使得人们很难想象癌前突变的细胞状态可变性如何给 上升为基底样乳腺癌。这项工作的长期目标是确定关键的细胞和分子 基底型乳腺癌遗传学基础的转变。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。我们发现癌前扩张伴随着 通过广泛招募特定的免疫亚群，表明它们在肿瘤发生中发挥关键作用。我们的 目标是将MADM与创新的方法相结合，以获得将识别 突变的上皮细胞内的细胞状态变异和癌前病变的浸润性免疫谱系。 假设上皮细胞的可塑性和间质微环境协调地使突变体多样化。 病变，揭示癌前转录状态，最终进展为乳腺基底细胞样癌 还有乳腺。该提案的目的是：1)定义共同的癌前轨迹 BRCA1-TP53缺乏症在小鼠和人类中引发的基底膜多样化。2)解除卷积 基底样乳房局部与特定癌前生态系统配对的免疫异质性 癌症。3)通过使用遗传学、药理学和 旁分泌扰动，在体外使癌前细胞的内在或外在变异性均一化。合作物价指数 简和宗在他们各自的肿瘤内细胞状态异质性和 拥有多年合作记录的基因工程小鼠建模。连同一对 资深临床医生，该团队准备对我们对基底样样疾病的理解产生重大的整体影响 乳房肿瘤的发生。

PROJECT SUMMARY/ABSTRACT 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 long-term goal of this work is to identify the critical cellular and molecular transitions underlying basal-like breast cancer genetics. 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. We found that premalignant expansion is accompanied by extensive recruitment of specific immune subsets, suggesting they play crucial roles in tumorigenesis. Our objective is to combine MADM with innovative methods for dissociation-free transcriptomics that will identify cell-state variabilities within mutant epithelial cells and the infiltrating immune lineages of a premalignancy. The hypothesis is that epithelial-cell plasticity and the stromal microenvironment coordinately diversify mutant lesions, revealing premalignant transcriptional states that ultimately progress to basal-like cancer in the breast and mammary gland. The aims of the proposal are: 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.