da Silva Tarcília Aparecida, Coelho Getúlio, Lorenzetti Bocca Anamélia, Figueiredo Cavalcante Neto Florêncio
Department of Oral Surgery and Pathology, School of Dentistry, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
J Cutan Pathol. 2007 Apr;34(4):315-23. doi: 10.1111/j.1600-0560.2006.00621.x.
Actinic keratosis (AK) is a premalignant lesion caused by ultraviolet (UV) radiation and characterized by epithelial and connective tissue alterations. However, little is known about the link between connective and UV-damaged epithelial tissues in AK.
To examine the potential relationship between connective tissue degeneration and molecular alterations in epithelial cells without evident morphologic changes, 30 cases of AK (8, grade I; 10, grade II; 12, grade III), divided into three grades according to the proportion of dermal elastosis (in grade I, up to 30% of collagen degeneration; in grade II, 30-60%; in grade III, more than 60%), were immunohistochemically analyzed for the expression of Ki67, p53, p63, bcl-2, E-cadherin, 34-betaE12, and CD99.
The increase in the solar elastosis grade was associated with an increase in positive cell numbers for all analyzed markers. Basal expression predominated in the lesions with low and moderate levels of connective tissue degeneration, while a basal and suprabasal expression pattern was prevalent in the lesions with high degeneration. In grade I and II lesions, proliferation marker, Ki67, expression was found to be significantly associated with the proapoptotic marker p53, while in grade III lesions, its expression was correlated with the anti-apoptotic marker, bcl-2.
These results demonstrate that the epithelial expression of apoptotic, cell proliferation, and structural proteins is augmented with the increase of the solar elastosis grade. Thus, the grade of solar elastosis could be a helpful morphologic marker in the assessment of neoplastic changes in sun-damaged skin.
光化性角化病（AK）是一种由紫外线（UV）辐射引起的癌前病变，其特征为上皮组织和结缔组织改变。然而，关于AK中结缔组织与紫外线损伤的上皮组织之间的联系，人们所知甚少。
为了研究在无明显形态学改变的情况下结缔组织退变与上皮细胞分子改变之间的潜在关系，选取30例AK（I级8例；II级10例；III级12例，根据真皮弹力组织变性比例分为三个等级，I级胶原变性达30%；II级为30%-60%；III级超过60%），对其进行免疫组织化学分析，检测Ki67、p53、p63、bcl-2、E-钙黏蛋白、34-βE12和CD99的表达。
日光性弹力组织变性等级增加与所有分析标志物的阳性细胞数增加相关。在结缔组织退变程度低和中等的病变中，主要为基底表达，而在退变程度高的病变中，基底和基底上表达模式较为普遍。在I级和II级病变中，增殖标志物Ki67的表达与促凋亡标志物p53显著相关，而在III级病变中，其表达与抗凋亡标志物bcl-2相关。
这些结果表明，随着日光性弹力组织变性等级的增加，凋亡、细胞增殖和结构蛋白的上皮表达增加。因此，日光性弹力组织变性等级可能是评估日光损伤皮肤肿瘤性变化的一个有用的形态学标志物。
