Jin L, Yang G Y, Auborn K
Department of Otolaryngology, Long Island Jewish Medical Center, The Long Island Campus of Albert Einstein College of Medicine, New York, USA.
Cell Prolif. 1998 Jun-Aug;31(3-4):127-38. doi: 10.1046/j.1365-2184.1998.00115.x.
Transcription factors belonging to the family of CAAT enhancer binding proteins (C/EBPs) programme differentiation in a wide variety of cells. We asked about the expression of C/EBPs in squamous epithelium. Using immunohistochemistry, C/EBPalpha and C/EBPbeta were easily detected in tissue sections from normal larynx or laryngeal papillomas, benign tumours with a papillomavirus aetiology and characterized by abnormal differentiation. A temporal expression of these C/EBPs occured as keratinocytes differentiated. In both tissues, C/EBPbeta appeared to be exclusively nuclear. In normal tissue, the greatest amount of C/EBPbeta was present in the spinous layer, and much less occurred in the granular layer. The basal layer of the laryngeal papillomas contained the most C/EBPbeta. Less was present in the spinous layer. Little C/EBPbeta was in the granular layer. Much C/EBPalpha was in the cytoplasm in both tissues. In normal tissue, nuclear C/EBPalpha staining was virtually absent in the basal layer, and became present in the spinous layer. Nuclear C/EBPalpha was randomly distributed in all layers in papillomas. Using immunoblots and Southwestern blots, we detected abundant truncated isoforms of C/EBPalpha in the papillomas. Since differentiation of many tissues is determined by the relative amounts of different C/EBPs, our data supports a role for C/EBPs in the differentiation of squamous epithelium.
属于CCAAT增强子结合蛋白（C/EBP）家族的转录因子可调控多种细胞的分化。我们研究了C/EBP在鳞状上皮中的表达情况。通过免疫组织化学方法，在正常喉组织或喉乳头状瘤（一种由乳头瘤病毒引起病因的良性肿瘤，其特征为异常分化）的组织切片中很容易检测到C/EBPα和C/EBPβ。随着角质形成细胞的分化，这些C/EBP呈现出一种时间性表达。在这两种组织中，C/EBPβ似乎仅存在于细胞核中。在正常组织中，C/EBPβ含量最多的是棘层，颗粒层中含量较少。喉乳头状瘤的基底层含有最多的C/EBPβ，棘层中含量较少，颗粒层中几乎没有C/EBPβ。在这两种组织中，C/EBPα大多存在于细胞质中。在正常组织中，基底层几乎没有C/EBPα的细胞核染色，而在棘层中出现。在乳头状瘤中，C/EBPα的细胞核染色在所有层中随机分布。通过免疫印迹和西南印迹法，我们在乳头状瘤中检测到大量截短的C/EBPα异构体。由于许多组织的分化是由不同C/EBP的相对含量决定的，我们的数据支持C/EBP在鳞状上皮分化中发挥作用。
