Precancer Niche Formation in the Fallopian Tube

背景：卵巢癌是妇科最致命的癌症。虽然有针对早期的根治疗法- 对于分期癌症，缺乏检测癌前病变的特定生物标志物，这种病变通常发生在 输卵管上皮细胞(FTE)。正常FTE由混合的分泌细胞和纤毛细胞组成 以大约1：1的比例。虽然FTE转化的机制还不完全清楚，但人们认为 卵泡液中的激素和生长因子使FTE在排卵期间暴露于遗传毒性应激，以及 逃避应激诱导的细胞死亡会导致分泌细胞的异常积累。在这 微环境中，分泌细胞有时会经历遗传和形态变化，包括 分层、异型性和细胞极性丧失，这些被认为是卵巢癌的前驱病变。 异常的分泌细胞聚集与卵巢癌的风险增加有关，而且更常见 在具有生殖系BRCA1突变的女性中。然而，这种形态变化和分子机制 导致分泌细胞转化的原因尚不清楚。具体地说，纤毛细胞在纤毛细胞的形成中的作用 前驱FTE损伤尚不清楚。 初步数据：我们对BRCA1突变携带者和非携带者FTE的组织学和分子分析 研究发现，绝经后BRCA1突变携带者的分泌细胞与纤毛细胞比率较高， 细胞生存相关基因CDK1和Survivin水平升高，表明分泌细胞逃逸 细胞死亡。出乎意料的是，我们观察到同型细胞分离和纤毛细胞的丢失先于 分泌细胞堆积。 假设：我们认为同型细胞信号和纤毛细胞的丢失创造了有利的 BRCA1突变体FTE中分泌细胞转化微环境 随着荷尔蒙的变化和基因毒性应激，天平向不受控制的增殖倾斜。 独特的资源：我们是第一个将诱导多能干细胞(IPSCs)分化为FTE和 从BRCA1突变携带者和非携带者中建立IPSC有机体。我们有最大的收藏品之一 来自高危患者的FTE标本的详细临床病理和人口学数据。我们将利用 我们最近开发的计算成像卷积神经网络流水线用于提取“隐藏” 生物标记物开发的癌前特征和潜在预防靶点的确定。 具体目标：在目标1中，我们将使用人和小鼠FTE有机化合物以及活体小鼠模型来测试 纤毛细胞保护分泌细胞免受遗传毒性压力的假说。在目标2中，我们将检验假设 在基因毒性应激下异常的分泌细胞存活可以被药物抑制剂所抵消 参与细胞存活的基因，如CDK1和Survivin。在目标3中，我们将整合RNA测序和 用深度神经网络学习的图像处理识别临床相关的分子和 BRCA1突变携带者输卵管癌前病变的组织形态计量学生物标志物。 影响：这项研究将有助于更好地理解易感基因突变之间的相互作用 以及卵巢癌发生前的微环境变化。识别潜在的分子和 癌前生态位形成的形态测量贡献者将有助于新策略的开发 用于卵巢癌的预防和检测，这是临床实践中迫切需要的。

Background: Ovarian cancer is the most fatal gynecologic cancer. While curative treatments exist for early- stage cancers, there is a lack of specific biomarkers for detecting preneoplastic lesions, which usually occur in the fallopian tube epithelia (FTE). Normal FTE consists of small clusters of secretory and ciliated cells intermixed in an approximately 1:1 ratio. Although the mechanism of FTE transformation is not fully understood, it is believed that hormones and growth factors in the follicular fluid expose FTE to genotoxic stress during ovulation and that escape from the stress-induced cell death leads to an aberrant accumulation of secretory cells. In this microenvironment, secretory cells sometimes undergo genetic and morphologic changes that include stratification, atypia, and loss of cell polarity, which are considered the precursor lesions to ovarian cancer. Aberrant secretory cell accumulation is associated with an increased risk of ovarian cancer and is more common in women with germline BRCA1 mutations. However, the morphologic changes and molecular mechanisms that lead to secretory cell transformation are unknown. Specifically, the role of ciliated cells in the formation of precursor FTE lesions is unknown. Preliminary data: Our histologic and molecular analyses of FTE from BRCA1 mutation carriers and non-carriers revealed that postmenopausal BRCA1 mutation carriers have a higher ratio of secretory to ciliated cells and increased levels of the cell survival-associated genes CDK1 and Survivin, suggesting that secretory cells escape cell death. Unexpectedly, we observed that homotypic cell segregation and loss of ciliated cells precede secretory cell accumulation. Hypothesis: We propose that homotypic cell signaling and loss of ciliated cells create a favorable microenvironment for secretory cell transformation in BRCA1 mutant FTE providing that other conditions, such as hormonal changes and genotoxic stress, coincide and tip the balance toward uncontrolled proliferation. Unique resources: We are the first group to differentiate induced pluripotent stem cells (iPSCs) into FTE and establish iPSC organoids from BRCA1 mutation carriers and non-carriers. We have one of the largest collections of FTE specimens with detailed clinicopathologic and demographic data from high-risk patients. We will leverage our recently developed computational imaging convolutional neural networks pipeline for extraction of “hidden” preneoplastic characteristics for biomarker development and identification of potential targets for prevention. Specific Aims: In Aim 1, we will use human and mouse FTE organoids and in vivo mouse models to test the hypothesis that ciliated cells protect secretory cells from genotoxic stress. In Aim 2, we will test the hypothesis that aberrant secretory cell survival under genotoxic stress can be counteracted by pharmacologic inhibitors of genes involved in cell survival, such as CDK1 and Survivin. In Aim 3, we will integrate RNA sequencing and image processing with deep-neural network learning to identify clinically-relevant molecular and histomorphometric biomarkers of preneoplastic lesions in fallopian tubes from BRCA1 mutation carriers. Impact: This research will lead to a better understanding of the interplay between predisposing genetic mutations and the microenvironmental changes that precede ovarian cancer initiation. Identifying potential molecular and morphometric contributors to the formation of the precancer niche will assist in the development of new strategies for ovarian cancer prevention and detection, which are urgently needed in clinical practice.