支气管上皮受压以自分泌方式调节表皮生长因子受体家族配体的表达。
Bronchial epithelial compression regulates epidermal growth factor receptor family ligand expression in an autocrine manner.
作者信息
Chu Eric K, Foley John S, Cheng Jason, Patel Anita S, Drazen Jeffrey M, Tschumperlin Daniel J
机构信息
Department of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, 75 Francis Street, Boston, MA 02115, USA.
出版信息
Am J Respir Cell Mol Biol. 2005 May;32(5):373-80. doi: 10.1165/rcmb.2004-0266OC. Epub 2005 Feb 10.
The epidermal growth factor receptor (EGFR), an important signaling pathway in airway biology, is stimulated by compressive stress applied to human airway epithelial cells. Although the EGFR ligand, heparin-binding epidermal growth factor-like growth factor (HB-EGF), is known to be released as a result of this stimulation, whether compressive stress enhances expression of other EGFR ligands, and the duration of mechanical compression required to initiate this response, is not known. Human airway epithelial cells were exposed to compressive stress, and expression of four EGFR ligands was examined by quantitative PCR. Cells were exposed to: (1) continuous compressive stress over 8 h, (2) compression with and without EGFR inhibitor (AG1478), or (3) time-limited compression (3.75, 7.5, 15, 30, and 60 min). Compressive stress produced a sustained upregulation of the EGFR ligands HB-EGF, epiregulin, and amphiregulin, but not transforming growth factor-alpha. Inhibition with AG1478 demonstrated that expression of HB-EGF, epiregulin, and amphiregulin is dependent on the signaling via the EGFR. Immunostaining for epiregulin protein demonstrated increased expression with compression and attenuation with EGFR inhibition. The response of all three EGFR ligands persisted long after the mechanical stimulus was removed. Taken together, these data suggest the possibility of a mechanically activated EGFR autocrine feedback loop involving selected EGFR ligands.
表皮生长因子受体(EGFR)是气道生物学中的一条重要信号通路,施加于人气道上皮细胞的压缩应力可刺激该通路。尽管已知表皮生长因子受体配体——肝素结合表皮生长因子样生长因子(HB-EGF)会因这种刺激而释放,但压缩应力是否会增强其他表皮生长因子受体配体的表达,以及引发这种反应所需的机械压缩持续时间尚不清楚。将人气道上皮细胞暴露于压缩应力下,通过定量聚合酶链反应检测四种表皮生长因子受体配体的表达。细胞被暴露于:(1)8小时的持续压缩应力;(2)有或没有表皮生长因子受体抑制剂(AG1478)的压缩;或(3)限时压缩(3.75、7.5、15、30和60分钟)。压缩应力使表皮生长因子受体配体HB-EGF、表皮调节素和双调蛋白持续上调,但不包括转化生长因子-α。AG1478抑制作用表明,HB-EGF、表皮调节素和双调蛋白的表达依赖于通过表皮生长因子受体的信号传导。对表皮调节素蛋白进行免疫染色显示,随着压缩表达增加,而随着表皮生长因子受体抑制表达减弱。在去除机械刺激后很长时间,所有三种表皮生长因子受体配体的反应仍然持续。综上所述,这些数据提示存在一种涉及特定表皮生长因子受体配体的机械激活的表皮生长因子受体自分泌反馈环的可能性。