The role of epidermal, fibroblast and endothelial cell COX-2 in skin cancer

表皮、成纤维细胞和内皮细胞COX-2在皮肤癌中的作用

• 批准号: 7804210
• 负责人: Harvey R. Herschman
• 金额: $ 20.1万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-30 至 2011-09-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7804210
• 关键词: Ablation; Adverse effects; Award; Cardiovascular system; Cells; Code; Data; Development; Endothelial Cells; Epithelial; Epithelial Cells; Excision; Exons; Fibroblasts; Figs - dietary; Frequencies; Genes; Genetic Transcription; Goals; Knockout Mice; Lead; Light; Malignant Neoplasms; Mediating; Mus; Myeloid Cells; Myofibroblast; PTGS2 gene; Papilloma; Parents; Pathway interactions; Preventive; Production; Prostaglandins; Protocols documentation; Relative (related person); Research; Role; Site; Skin; Skin Cancer; Skin Neoplasms; Stream; Therapeutic; Tissues; Transgenic Mice; Translations; Tumor Promotion; carcinogenesis; cell type; cyclooxygenase 2; inhibitor/antagonist; macrophage; monocyte; promoter; protein expression; public health relevance; receptor; recombinase; research study; tumor progression

DESCRIPTION (provided by applicant): In the parent application for this supplement, R01CA123055, we described specific aims to determine (i) in which cell type(s) COX-2 must be expressed for skin cancer induction, using the DMB/TPA and UV-B protocols, and (ii) in which cell type(s) skin cancer induction can be modulated by COX-2 over expression. We generated "floxed" Cox2 (Cox2flox) mice in which critical Cox2 exons are flanked by loxP sites and COX-2 conditional over expresser (COX-2 COE) transgenic mice in which the CAG promoter drives COX-2 protein expression. However, the CAG promoter is separated from the COX-2 coding region by a floxed transcription/translation STOP sequence in the COX-2 COE mouse. We planned to determine, by crossing Cox2flox mice with mice that express Cre recombinase in a tissue specific fashion, in which cell type(s) COX-2 must be expressed for skin cancer induction by DMBA/TPA and/or UV-B. When the Cox2 gene is deleted in skin epithelial cells (by crossing Cox2flox mice with Keratin14CreTg mice) DMBA/TPA skin tumor formation is extensively inhibited. In contrast - and surprisingly, we think - when the Cox2 gene is deleted in macrophage/monocytes (by crossing Cox2flox mice with LysMCreTg mice) skin tumor formation is increased, relative to littermate controls. COX-2 mediated prostaglandin (PG) formation in epithelial cells and in monocyte/macrophages has distinctly different roles in skin cancer development. In light of our data demonstrating distinct roles for COX-2 mediated PG expression in different cells during skin cancer progression, we add a third goal in this supplement application: We wish to ask "Can COX-2 expression in a single cell type, from the endogenous Cox2 promoter, mediate/modulate DMBA/TPA or UV-B induced skin cancer?" For example, can "endogenous" COX-2 expression from epithelial cells, without COX-2 expression in other cells, suffice for DMBA/TPA skin cancer induction? To answer this question we will develop Cox2 cell-restricted (Cox2Cr) mice in which the endogenous Cox2 gene is functionally silenced, unless a suppressing STOP sequence is removed by cell type-specific Cre excision. PUBLIC HEALTH RELEVANCE: COX-2 inhibitors are still investigated as therapeutic and preventive agents for epithelial cancers, despite cardiovascular side effects. "Down-stream" COX-2 pathway effectors (prostanoid synthases and receptors) have become targets for similar research. If we can pinpoint the cell type(s) in which COX-2 expression and the prostanoid effectors regulate cancer development, we may be able to target those steps with lower concentrations and less prolonged application of pharmacologic agents. We anticipate we will be able to define the critical cells for COX-2 cancer enhancement and suppression.

描述（由申请人提供）：在此补充的父申请中，R01CA123055，我们描述了特定的目的，以确定（i）必须使用DMB/TPA和UV-B方案来表达以下细胞类型的COX-COX-COX-COX-2，以及（II）在哪种细胞类型的皮肤癌诱导中可以通过Cox-cox-coce cox-cosexpersepments进行调制。我们生成了“ Floxed” Cox2（Cox2flox）小鼠，其中关键的Cox2外显子侧面是Loxp位点的侧面，而COX-2则与Expresser（COX-2 COE）转基因小鼠有关，CAG启动子在其中驱动Cox-2蛋白表达。但是，CAG启动子通过COX-2 COE小鼠中的Flox transcription/Transcration Stop序列与COX-2编码区分开。我们计划通过将Cox2Flox小鼠与以组织特异性方式表达CRE重组酶的小鼠跨越COX2FLOX小鼠，其中必须通过DMBA/TPA和/或UV-B表达细胞类型COX-C，以诱导皮肤癌。当Cox2基因被删除在皮肤上皮细胞中时（通过将Cox2flox小鼠与角蛋白14CRETG小鼠交叉）DMBA/TPA皮肤肿瘤形成得以广泛抑制。相反，我们认为 - 当Cox2基因在巨噬细胞/单核细胞中删除时（通过将Cox2flox小鼠与乳胶小鼠穿越COX2FLOX小鼠）相对于静物对照组的增加时，就会增加COX2基因（通过将COX2FLOX小鼠穿过Cox2Flox小鼠）时。 COX-2介导的上皮细胞和单核细胞/巨噬细胞中的前列腺素（PG）形成在皮肤癌发育中具有明显不同的作用。 鉴于我们的数据表明，在皮肤癌进展过程中，COX-2在不同细胞中介导的PG表达的不同作用，我们在此补充应用中添加了第三个目标：我们希望“我们想问“ COX-2在单个细胞类型中的COX-2表达，来自内源性COX2启动子，介导/调节DMBA/TPA或UV-B诱导的皮肤癌？”例如，在其他细胞中没有COX-2表达的上皮细胞中“内源性” COX-2表达是否足以诱导DMBA/TPA皮肤癌？为了回答这个问题，我们将开发COX2细胞限制的（COX2CR）小鼠，其中内源性COX2基因在功能上沉默，除非通过细胞类型特异性CRE切除去除抑制的停止序列。 公共卫生相关性：尽管心血管副作用，COX-2抑制剂仍被研究为上皮癌的治疗和预防剂。 “下游” COX-2途径效应子（前列腺素合酶和受体）已成为类似研究的靶标。如果我们可以确定COX-2表达和前列腺素效应子调节癌症发展的细胞类型，那么我们可能能够以较低浓度且延长药理学剂的延长应用来瞄准这些步骤。我们预计我们将能够为COX-2癌症增强和抑制定义关键细胞。