Functional exploration of progenitor renewal and differentiation in oral epithelial homeostasis and cancer

口腔上皮稳态和癌症中祖细胞更新和分化的功能探索

基本信息

批准号：
10677648
负责人：
ZHE YING
金额：
$ 24.56万
依托单位：
ICAHN SCHOOL OF MEDICINE AT MOUNT SINAI
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-09-02 至 2024-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10677648
关键词：
Acceleration Apoptosis Bar Codes Binding Bioinformatics Biological Assay Candidate Disease Gene Cell Cycle Cell Cycle Arrest Cell Cycle Regulation Cell Differentiation process Cells Chromosomes Clonal Expansion Data Development Disadvantaged Epithelial Cells Epithelium Exposure to Foundations Future Gene Expression Profile Genes Genetic Genetic Screening Genetic Transcription Goals Growth Head and Neck Squamous Cell Carcinoma Homeostasis Human papilloma virus infection Injections Knowledge Lentivirus Lesion Maintenance Malignant Neoplasms Measures Mediating Mitotic Modeling Molecular Mus Mutate Mutation Oncogenes Oncogenic Oral PIK3CA gene PIK3CG gene Pathway interactions Patients Pattern Phase Placenta Population Publishing Research Research Personnel Signal Induction Signal Transduction Stratified Epithelium Stromal Cells TP53 gene Testing Tissues Tobacco use Training Tumor Promotion Work cancer type craniofacial epithelial stem cell genome-wide improved in vivo inflammatory milieu insight knockin animal maxillofacial multiple omics mutant new therapeutic target novel novel therapeutic intervention oral cavity epithelium oral tumorigenesis patient prognosis postmitotic progenitor programs promoter senescence stem cell fate stem cell niche stem cells tumor tumor initiation tumor microenvironment tumorigenesis

项目摘要

Project Summary Head and neck squamous cell carcinoma (HNSCC) is the most common cancer type initiated from stratified epithelium of oral and maxillofacial region. Despite great effort to characterize HNSCC via high throughput multi-omics approaches, significant improvements in patient prognosis are yet to be made. This is largely due to incomplete understanding of how cancer-associated lesions reprogram epithelial cells to expand and transform, at cellular and molecular levels. Stratified epithelium is a tissue characterized by (a) highly proliferative basal progenitor cells, (b) progenitor differentiation which is accompanied by complete loss of mitotic potential, and (c) stem cell fate choice between the proliferative progenitor and differentiated postmitotic states. As such, growth rate of stratified epithelia is controlled by balancing rates of renewal and differentiation. In my recently published work, I found that oncogenic activation of Pik3ca, the most commonly mutated oncogene in HNSCC, results in growth disadvantage in stratified epithelia. Using direct measure of cell fate choice in vivo, I found that oncogenic PI3K signaling induces differentiation. This serves to counterbalance accelerated cell cycle independently of senescence or apoptosis, and acts as a dominant cellular mechanism to restrict clonal expansion. Building on that study, my current proposal will test the hypothesis that genetic lesions and niche factors found in PI3K mutant HNSCC promote tumorigenesis by overcoming oncogene- induced differentiation. In my preliminary work I used multiple rounds of genetic screens in vivo to identify renewal promoters among ~500 patient-derived lesions associated with PIK3CA mutations. Through this large- scale effort I identified the minimal combination of lesions required to overcome PI3K induced differentiation and initiate HNSCC formation. Among these lesions, loss of Trp53 acts as a primary renewal promoter. Using a canonical p53 function deficient Trp533KR/3KR knock-in animal, I found that Trp53 loss drives HNSCC by promoting renewal, and independent of cell cycle arrest, senescence and apoptosis. By comparing chromosome accessibility between WT, Trp533KR/3KR and Trp53-/- epithelium I found that p53 can transcriptionally suppress key renewal genes, and I propose to study the importance of these genes for p53- mediated progenitor differentiation. In parallel, I identified secretory factors specifically expressed in HNSCC progenitor niche. I used a genetic screen to test their potential to overcome PI3K induced differentiation. With a novel intra-placenta lentivirus injection strategy, I am able to infect a spectrum of stromal cells present in niche of stratified epithelium. Thus, I will functional test key pro-renewal factors in stromal cells during HNSCC initiation to uncover the underlying molecular pathways mediating epithelial renewal. In summary, my preliminary data identify key genetic lesions and secreted niche factors that may drive HNSCC formation by overcoming PI3K induced differentiation. My proposal will continue to test this model, with the ultimate goal of uncovering molecular mechanism of how PI3K induced differentiation barrier is breached in HNSCCs.

项目概要头颈鳞状细胞癌（HNSCC）是分层起始的最常见癌症类型口腔颌面部的上皮细胞。尽管付出了巨大的努力来通过高通量表征 HNSCC 多组学方法尚未显着改善患者预后。这很大程度上是由于不完全了解癌症相关病变如何重新编程上皮细胞以扩展和在细胞和分子水平上进行转化。复层上皮是一种具有以下特征的组织：（a）高度增殖的基底祖细胞，（b）祖细胞分化，伴随着完全丧失有丝分裂潜力，以及（c）增殖祖细胞和分化的有丝分裂后细胞之间的干细胞命运选择州。因此，复层上皮的生长速率是通过平衡更新和分化速率来控制的。在我最近发表的工作中，我发现 Pik3ca（最常见的突变）的致癌激活 HNSCC 中的癌基因导致复层上皮生长不利。使用细胞命运的直接测量在体内选择中，我发现致癌 PI3K 信号传导会诱导分化。这起到了平衡作用加速细胞周期，独立于衰老或凋亡，并作为主导细胞机制限制克隆扩张。在此研究的基础上，我目前的提议将检验基因假设 PI3K 突变型 HNSCC 中发现的病变和生态位因子通过克服癌基因促进肿瘤发生诱导分化。在我的前期工作中，我使用了多轮体内遗传筛选来识别约 500 个与 PIK3CA 突变相关的患者源性病变中的更新促进剂。通过这个大—— 我确定了克服 PI3K 诱导分化所需的最小病变组合并启动 HNSCC 形成。在这些病变中，Trp53 的缺失充当主要的更新促进剂。使用典型的 p53 功能缺陷 Trp533KR/3KR 敲入动物，我发现 Trp53 缺失通过以下方式驱动 HNSCC 促进更新，并且独立于细胞周期停滞、衰老和凋亡。通过比较 WT、Trp533KR/3KR 和 Trp53-/- 上皮之间的染色体可及性我发现 p53 可以转录抑制关键的更新基因，我建议研究这些基因对 p53- 的重要性介导的祖细胞分化。与此同时，我确定了 HNSCC 中特异表达的分泌因子祖先生态位。我使用基因筛选来测试它们克服 PI3K 诱导分化的潜力。与一个新颖的胎盘内慢病毒注射策略，我能够感染微环境中存在的一系列基质细胞复层上皮。因此，我将在 HNSCC 期间对基质细胞中的关键促更新因子进行功能测试开始揭示介导上皮更新的潜在分子途径。总而言之，我的初步数据确定了可能通过以下方式驱动 HNSCC 形成的关键遗传病变和分泌的生态位因子：克服 PI3K 诱导的分化。我的建议将继续测试这个模型，最终目标是揭示了 HNSCC 中 PI3K 诱导的分化屏障如何被破坏的分子机制。