Mechanisms of the Stromal Response to Smoothened Inhibition in Pancreatic Cancer

胰腺癌平滑抑制的基质反应机制

• 批准号: 8084639
• 负责人: Kenneth P Olive
• 金额: $ 33.41万
• 依托单位: COLUMBIA UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-03-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8084639
• 关键词: Ablation; Adrenal Glands; Adult; Affect; Alleles; Angiogenic Factor; Angiogenic Peptides; Antineoplastic Agents; Basal Cell; Basal Cell Nevus Syndrome; Basal cell carcinoma; Behavior; Binding; Biology; Cell Communication; Cell Proliferation; Cells; Clinical; Clinical Trials; Colorectal Cancer; Data; Desmoplastic; Development; Disease; Drug Delivery Systems; Ductal; Endothelial Cells; Epithelial; Epithelial Cells; Epitopes; Erinaceidae; Extracellular Matrix; Fibroblasts; Future; Gene Expression; Gene Targeting; Genes; Genetic; Genetically Engineered Mouse; Glioblastoma; Goals; Immunofluorescence Immunologic; In Vitro; Inherited; Large Intestine Carcinoma; Learning; Ligands; Lung; Maintenance; Malignant Neoplasms; Malignant neoplasm of esophagus; Malignant neoplasm of pancreas; Malignant neoplasm of prostate; Mediating; Mediator of activation protein; Mesenchymal; Mesenchyme; Molecular; Molecular Biology; Mutation; Neoplastic Epithelial Cell; Organ; Ovarian Carcinoma; Pancreatic Ductal Adenocarcinoma; Pancreatic carcinoma; Paracrine Communication; Pathway interactions; Pattern; Pharmaceutical Preparations; Play; Predisposition; Process; Reporter; Resolution; Role; Signal Transduction; Source; Stromal Cells; System; Testing; Therapeutic; Tissues; Tumor Tissue; Variant; Vascular Endothelial Growth Factors; Vascularization; Work; Wound Healing; angiogenesis; autocrine; cancer genetics; cancer type; cell type; chemotherapy; design; human SMO protein; in vivo; inhibitor/antagonist; insight; loss of function mutation; lung small cell carcinoma; malignant breast neoplasm; malignant stomach neoplasm; medulloblastoma; melanoma; mouse model; neoplastic cell; overexpression; pancreatic neoplasm; paracrine; pre-clinical; preclinical study; promoter; prostate carcinogenesis; research study; response; restoration; smoothened signaling pathway; transcription factor; tumor; tumorigenesis

DESCRIPTION (provided by applicant): The Hedgehog signaling pathway is overexpressed in a variety of cancers, leading to hyperactivation of target genes in Hh responding cells.1 In a number of cancers, the responding cells are stromal fibroblasts that are found near Hh ligand-expressing epithelial cells.2-5 This paracrine mechanism is one of many cell-cell interactions that take place between epithelial and mesenchymal cells. Through its role as a master regulator of other transcription factors, Hh pathway activation can have extremely potent effects on cell proliferation, behavior and survival. In pancreatic ductal adenocarcinoma (PDA), paracrine signaling from neoplastic epithelial cells to fibroblasts controls the development and maintenance of stromal desmoplasia, a very prominent feature of these tumors.4-7 We previously found that stromal desmoplasia in PDA contributes to primary chemoresistance by interfering with drug delivery.7 Inhibiting the Hh pathway with a targeted inhibitor of Smoothened (Smo) depleted the stroma from pancreatic tumors arising in a genetically engineered mouse model. This had the effect of facilitating drug delivery to the tumor parenchyma, ultimately aiding in their treatment and leading to prolonged survival. However, the precise molecular mechanisms by which Smo inhibitors target desmoplasia is unclear. To learn more about how Smo inhibitors affect stromal cells, we will examine the functional and molecular consequence of Smo inhibition in a genetically engineered mouse model of PDA. We will perform ChIP-SEQ for the downstream transcription factor Gli2 on pancreatic tumor tissues and compare the results to changes in global gene expression induced by Smo inhibition, providing insight into the differentially regulated genes whose promoters are bound by Gli transcription factors. Another effect of Smo inhibition in pancreatic tumors is the restoration of tissue vascularization, which is oddly low in pancreatic cancer. This paradoxical result is at odds with the known roles of the Hh pathway during angiogenesis. We hypothesize that angiogenesis occurs after Smo inhibition due to the relief of an anti- angiogenic signal provided by fibroblasts. We will test this by using hedgehog-independent means of depleting the stroma, and by examining several possible stroma-mediated mechanisms using tissues derived from genetically engineered mice. These experiments will leverage our expertise in mouse modeling, preclinical therapeutics and molecular biology to determine the basic mechanisms of Smo inhibition in pancreatic cancer and other systems employing paracrine Hh signaling. Currently, 25 different clinical trials have been initiated to investigate Smo inhibitors in 9 different cancers, including PDA. The experiments proposed here will aid our understanding of their results and assist in the design of future trials. More generally, we will learn about the relationship between epithelial and mesenchymal cells and the pathways that promote stromal desmoplasia in cancer. PUBLIC HEALTH RELEVANCE: The goal of this proposal is to learn how a new class of anticancer agent works at the molecular level. "Smoothened inhibitors" have recently entered clinical trials for 9 different types of cancer, including pancreatic cancer. This proposal uses preclinical trials in pancreatic cancer to better understand the effects of Smoothened inhibitors.

描述（由申请人提供）：刺猬信号通路在多种癌症中过表达，导致HH响应细胞中靶基因的过度激活。1在许多癌症中，响应细胞是基质成纤维细胞，它们是hH rigand celts的相互作用的相互作用的一个paractial collials.2-间充质细胞。通过作为其他转录因子的主要调节剂的作用，HH途径激活对细胞增殖，行为和生存具有极有效的影响。在胰腺导管腺癌（PDA）中，从肿瘤上皮细胞到成纤维细胞的旁分泌信号传导控制了基质脱虫质质量的发展和维持，这些肿瘤的突出特征，这些肿瘤的一个非常重要的特征。平滑（SMO）的靶向抑制剂耗尽了基因工程小鼠模型中产生的胰腺肿瘤的基质。这具有促进药物递送到肿瘤实质的效果，最终有助于其治疗并导致长期生存。然而，尚不清楚SMO抑制剂靶向脱粒的精确分子机制。 为了了解有关SMO抑制剂如何影响基质细胞的更多信息，我们将检查SMO抑制的功能和分子后果，在基因工程的PDA小鼠模型中。我们将对胰腺肿瘤组织的下游转录因子GLI2进行CHIP-SEQ，并将结果与​​SMO抑制诱导的全局基因表达的变化进行比较，从而洞悉促进子的促进子受GLI转录因子绑定的差异调节基因。 SMO抑制在胰腺肿瘤中的另一个作用是恢复组织血管形成，这在胰腺癌中奇怪。这种矛盾的结果与血管生成期间HH途径的已知作用不一致。我们假设由于成纤维细胞提供的抗血管生成信号的缓解，血管生成发生在SMO抑制后发生。我们将通过使用刺猬独立的方法来耗尽基质的方法，并使用源自基因工程小鼠的组织来测试这一点。 这些实验将利用我们在小鼠建模，临床前疗法和分子生物学方面的专业知识来确定胰腺癌和其他采用旁分泌HH信号传导的SMO抑制作用的基本机制。目前，已经开始了25项不同的临床试验，以研究包括PDA在内的9种不同癌症中的SMO抑制剂。这里提出的实验将有助于我们理解他们的结果，并有助于设计未来的试验。更一般地，我们将了解上皮细胞和间质细胞之间的关系以及促进癌症中基质脱木质质的途径。 公共卫生相关性：该提案的目的是学习新类别的抗癌剂在分子层中如何起作用。 “平滑抑制剂”最近针对包括胰腺癌在内的9种不同类型的癌症进行了临床试验。该建议使用胰腺癌的临床前试验，以更好地了解平滑抑制剂的影响。