Model of chemotherapy-induced mucositis

描述(申请人提供)：口腔和食道粘膜炎是癌症化疗的常见副作用。严重的口腔粘膜炎可能会非常痛苦，因此可能需要减少剂量和/或推迟抗肿瘤治疗。尽管这些病变具有临床意义，但特定的细胞事件与它们的发病机制有关 人们对此知之甚少，因此目前缺乏分子靶向治疗或预防策略。对高度增殖的基底上皮细胞的细胞毒性是导致消化道粘膜组织损伤的关键因素；然而，越来越清楚的是，炎症级联反应的激活和微生物的失调也可能在病变的发生发展中发挥重要作用。关于微生物在粘膜炎的发生或发展中的作用，文献中缺乏共识，因为多菌定植的相关实验模型还不存在。我们建议使用我们建立的口腔和食道粘膜的三维系统，其中包括唾液和营养流动，以开发新的体外粘膜损伤模型，模拟人类化疗引起的粘膜炎。这些模型将提供一个生物相关的框架，其中可以在细胞和分子水平上剖析化疗药物的作用机制，并且可以在损伤的发展或解决期间“实时”检查当地微生物菌群的影响。所提出的模型的新颖性和意义在于，它们提供了介于单细胞类型培养和人类器官培养之间的组织复杂性，并整合了唾液/营养流动和接触共生微生物群落，从而再现了人类口腔环境的条件。这种体外模型在这种疾病的病理生物学中的应用是新颖的，也是潜在的范式转变。在第一个目标中，我们将建立一个临床相关的体外药物诱导的粘膜损伤模型，表征口腔和食道细胞的凋亡和促炎反应，并使用口腔粘膜炎的小鼠模型进行验证。在第二个目标中，我们将使用口腔和食道体外模型以及小鼠口腔粘膜炎模型，证明化疗诱导的粘膜改变允许共生细菌和真菌物种优先定植，这些细菌和真菌物种可能导致炎症和组织损伤。这项工作将为设计新型的联合抗菌药物和促进伤口愈合的策略，以控制上消化道粘膜炎病变及其相关的多菌感染奠定基础。1

DESCRIPTION (provided by applicant): Oral and esophageal mucositis are common side effects of cancer chemotherapy. Severe oral mucositis can be sufficiently painful so that dose reductions and/or postponement of anti-neoplastic treatments may be necessary. Despite the clinical significance of these lesions, the specific cellular events involved in their pathogenesis are poorly understood and thus molecularly-targeted therapies or prevention strategies are currently lacking. Cytotoxicity to the highly proliferative basal epithelial cells is a key factor hat initiates tissue injury in the alimentary tract mucosa; however, it is becoming increasingly clear that activation of inflammatory cascades and microbial dysbiosis may also play major roles in the development or progression of the lesions. There is lack of consensus in the literature regarding the role of microorganisms in the initiation or progression of mucositis since relevant experimental models of polymicrobial colonization of are non-existent. We propose to use our established three-dimensional systems of the oral and esophageal mucosa which incorporate salivary and nutrient flow, to develop novel in vitro mucosal injury models that mimic chemotherapy-induced mucositis in humans. These models will provide a biologically relevant framework where mechanisms of action of chemotherapy medications can be dissected at the cellular and molecular levels and where the effect of the local microbial flora can be examined "in real time" during development or resolution of the injury. The novelty and significance of the proposed models is that they provide an organizational complexity that is between the culture of single cell types and human organ cultures, and integrate salivary/nutrient flow and exposure to commensal microbial consortia, which reproduce conditions of the oral environment in humans. The application of such in vitro models in the pathobiology of this condition is novel and potentially paradigm shifting. In the first aim we will establish a clinically relevant pharmacologically-induced in vitro model of mucosal injury, characterize the apoptotic and proinflammatory responses of oral and esophageal cells and validate these using a mouse model of oral mucositis. Using the oral and esophageal in vitro models as well as a mouse oral mucositis model in the second aim we will show that chemotherapy-induced mucosal alterations allow preferential colonization of commensal bacterial and fungal species that can contribute to inflammation and tissue damage. This work will lay the foundation for the design of novel combined antimicrobial and wound healing promoting strategies to control mucositis lesions of the upper alimentary tract and their associated polymicrobial infections. 1