Regulation Of Differentiation In Lung And Epidermal Kera

肺和表皮角质层分化的调节

• 批准号: 6837504
• 负责人: Anton M Jetten
• 金额: --
• 依托单位: NATIONAL INSTITUTE OF ENVIRONMENTAL HEALTH SCIENCES
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6837504
• 关键词: biotransformation; bronchus; carcinogenesis; cell differentiation; cell growth regulation; cell proliferation; clinical research; developmental genetics; esophagus; functional /structural genomics; gene environment interaction; gene expression; gene targeting; genetic regulation; genetically modified animals; human tissue; keratinocyte; laboratory mouse; lung neoplasms; microarray technology; mucins; p53 gene /protein; peroxisome proliferator activated receptor; respiratory epithelium; retinoids; squamous cell carcinoma; trachea

I. The trachea and esophagus have a common origin evolving from the foregut endoderm during early embryonic development. These epithelia undergo a series of well-defined structural changes involving differentiation of progenitor cells into several cell types that ultimately result in the formation of the mature epithelium. In this study, we monitor the expression of p63 in the esophageal and tracheobronchial epithelium at several stages during development and determine the effect of the lack of p63 expression on the morphogenesis of these epithelia in p63-/- mice. At day E15.5, the esophageal and tracheobronchial epithelium contain 2-3 layers of cells; however, only the progenitor cells express p63. The progenitor cells differentiate first into ciliated cells (p63-/b-tubulin IV+) and at birth into basal cells (p63+/K14+/BS-I-B4+). In adult mouse and human, the lining of the esophagus matures into a (non)keratinizing, stratified epithelium while the tracheobronchial lining develops into a pseudostratified, columnar epithelium containing basal, ciliated and mucosecretory cells. In mature epithelia, the K14+/BS-I-B4+ basal cells are the most intensely stained for p63. Expression of p63 is dramatically repressed during squamous differentiation in vivo or in cultured cells. Generally, human squamous cell carcinomas stained strongly while human adenocarcinomas did not stain for p63. In contrast to the esophagus and trachea from wild type mice, the esophageal and tracheobronchial epithelium from newborn p63-/- mice consist largely of a columnar, ciliated epithelium that appear to lack basal cells. Our study indicates that p63 is critical for normal morphogenesis of the esophageal and tracheobronchial epithelium. In p63-/- mice, progenitor cells are able to differentiate into ciliated cells but do not appear to generate basal cells suggesting a role for p63 either in the regulation of the differentiation of progenitor cells into basal cells or in the survival of basal cells. II. Retinoids play an important role in the tracheobronchial epithelium. Retinoids can act via nuclear retinoid receptors or through other mechanisms. The synthetic retinoid 6-[3-(1-adamantyl)-4-hydroxyphenyl]-2-naphthalene carboxylic acid (AHPN) can act both activate RARgamma and act by receptor-independent mechanisms. We have analyzed the effect of several retinoids on the expression of non-steroidal anti-inflammatory drug-activated gene (NAG-1) in normal human tracheobronchial epithelial (HTBE) cells and several lung carcinoma cell lines. The retinoid AHPN greatly enhances the expression of NAG-1 mRNA and protein in a time and dose-dependent manner in human lung adenocarcinoma H460 cells and several other carcinoma cell lines. This induction was specific for AHPN since retinoic acid, an RAR- and an RXR-pan-agonist were unable to induce NAG-1 suggesting that this induction is not mediated through activation of retinoid receptors. Although NAG-1 is a p53-responsive gene, AHPN-induced NAG-1 expression does not require p53. The induction of NAG-1 expression by AHPN is at least in part due to a 8-fold increase in the stability of NAG-1 mRNA. In contrast to carcinoma cells, NAG-1 expression is effectively induced by retinoic acid and the RAR-selective pan-agonist in normal HTBE cells and accompanies the inhibition of squamous differentiation and the initiation of normal differentiation. In vivo, NAG-1 expression was observed in the normal tracheobronchial epithelium while no expression was found in either squamous metaplastic tracheal epithelium or in sections of human lung tumors. Our results suggest that the induction of NAG-1 expression by retinoids in normal HTBE and lung carcinoma cells is regulated by distinct mechanisms and is associated with different biological processes. The linkage between AHPN treatment and NAG-1 expression revealed in this study provides a new mechanism for the anti-tumorigenic activity of AHPN.

I.气管和食道在早期胚胎发育期间从前肢内胚层演变出来。这些上皮经历了一系列定义明确的结构变化，涉及祖细胞分化为几种细胞类型，最终导致成熟上皮形成。在这项研究中，我们监测发育过程中多个阶段的食管和气管上皮细胞中p63的表达，并确定缺乏p63表达对p63 - / - 小鼠中这些上皮的形态发生的影响。在E15.5天，食管和气管支气管上皮含有2-3层细胞。但是，只有祖细胞表达p63。祖细胞首先将其分化为纤毛细胞（p63-/b-微管蛋白IV+），并在出生中分为基底细胞（p63+/k14+/bs-i-b4+）。在成年小鼠和人类中，食道的衬里成熟成（非）角质化，分层的上皮，而气管支气管内衬则成长为含有基础，纤毛和粘膜分泌细胞的假性柱状，柱状上皮。在成熟的上皮中，K14+/BS-I-B4+基底细胞是p63最强烈的染色。在体内或培养细胞中的鳞状分化过程中，p63的表达受到了极大的抑制。通常，人类鳞状细胞癌强烈染色，而人腺癌对p63没有染色。与野生型小鼠的食道和气管相反，新生儿p63 - / - 小鼠的食管和气管支气管上皮在很大程度上是由柱状上皮组成的，似乎缺乏碱细胞。我们的研究表明，p63对于食管和气管支气管上皮的正常形态发生至关重要。在p63 - / - 小鼠中，祖细胞能够分化为纤毛细胞，但似乎没有产生基底细胞，这表明p63在调节祖细胞分化为基底细胞或基底细胞的存活中起作用。 ii。类视网膜类动物在气管支气管上皮中起重要作用。类维生素类动物可以通过核视黄素受体或其他机制作用。合成性视网膜类似6- [3-（1-亚氨烷）-4-羟基苯基] -2-萘甲苯羧酸（AHPN）可以通过不依赖受体的机制来激活Rargamma和ACT。我们已经分析了几类类视丁素对正常人气管上皮细胞（HTBE）细胞和几种肺癌细胞系中非甾体类抗炎药激活基因（NAG-1）表达的影响。类视感AHPN大大增强了人类肺腺癌H460细胞和其他几种癌细胞系中Nag-1 mRNA和蛋白质的表达和剂量依赖性方式。这种诱导是针对AHPN的特异性，因为视黄酸，RAR-和RXR-PAN激动剂无法诱导NAG-1，这表明这种诱导不是通过激活性类维生素性受体介导的。尽管NAG-1是p53响应基因，但AHPN诱导的NAG-1表达不需要p53。 AHPN诱导NAG-1表达至少部分是由于Nag-1 mRNA的稳定性增加了8倍。与癌细胞相比，在正常HTBE细胞中，视黄酸和RAR选择性泛 - 启动器有效诱导NAG-1表达，并伴随着鳞状分化和正常分化的抑制。在体内，在正常的气管支气管上皮中观察到NAG-1表达，而在鳞状化生性气管上皮或人肺肿瘤的部分中均未发现表达。我们的结果表明，类维生素类动物在正常HTBE和肺癌细胞中诱导NAG-1表达的诱导受不同的机制调节，并且与不同的生物学过程有关。在这项研究中揭示的AHPN处理与NAG-1表达之间的联系为AHPN的抗肿瘤活性提供了新的机制。