Calikoglu Emel, Chavaz Pierre, Saurat Jean-Hilaire, Kaya Gürkan
Department of Dermatology, Fatih University Medical Faculty, Ankara, Turkey.
Dermatology. 2003;207(1):104-6. doi: 10.1159/000070959.
Dermatofibroma (DF) is a common benign histiocytic tumor, which has several clinicopathological variants. Myxoid DF is one of these variants, which is characterized by a stromal mucin deposition. CD44 is a polymorphic transmembrane glycoprotein and the principal cell surface receptor of hyaluronate (HA), the major component of the extracellular matrix. In a recent study, we have observed an abnormal accumulation of HA in the superficial dermis of transgenic mice with a keratinocyte-specific CD44 expression defect. We have also shown that HA was accumulated in large amounts in the superficial dermis of lichen sclerosus et atrophicus (LSA) lesions and that the epidermal CD44 expression of LSA skin was significantly decreased or lost. In an another study, we have suggested that a decrease in CD44 expression in follicular epithelial proliferations might be correlated with an abnormal HA accumulation in perifollicular solitary cutaneous myxoma. Recently we have also demonstrated that classical DF lesions displayed a strong CD44 expression in tumor cells and a weak HA positivity in tumor stroma whereas CD44 expression was significantly reduced or absent in dermatofibrosarcoma lesions and the tumor stroma showed strong HA staining.
Here we present 3 cases of myxoid DF, in which we explored the nature of the mucinous material in myxoid stroma by colloidal iron and hyaluronic acid binding protein stainings, as well as the expression of CD44 in the tumor cells by immunohistochemistry.
We show that HA is accumulated in the stroma of all myxoid DF lesions with a significant decrease in CD44 expression in the tumor cells.
Our results suggest that a decrease in CD44 expression in the tumor cells may result in stromal myxoid changes characterized by an abnormal HA accumulation in myxoid DF.
皮肤纤维瘤（DF）是一种常见的良性组织细胞肿瘤，有多种临床病理变异型。黏液样DF是其中一种变异型，其特征为间质黏蛋白沉积。CD44是一种多态性跨膜糖蛋白，是透明质酸（HA）的主要细胞表面受体，而透明质酸是细胞外基质的主要成分。在最近的一项研究中，我们观察到角质形成细胞特异性CD44表达缺陷的转基因小鼠的浅表真皮中HA异常蓄积。我们还表明，硬化性萎缩性苔藓（LSA）皮损的浅表真皮中大量蓄积HA，且LSA皮肤的表皮CD44表达显著降低或缺失。在另一项研究中，我们提出毛囊上皮增殖中CD44表达的降低可能与毛囊周围孤立性皮肤黏液瘤中HA异常蓄积有关。最近我们还证明，经典DF皮损的肿瘤细胞中CD44表达强烈，肿瘤间质中HA阳性较弱，而皮肤纤维肉瘤皮损中CD44表达显著降低或缺失，且肿瘤间质显示强烈的HA染色。
本文报告3例黏液样DF，通过胶体铁和透明质酸结合蛋白染色探讨黏液样间质中黏液物质性质，并用免疫组化检测肿瘤细胞中CD44的表达。
我们发现所有黏液样DF皮损的间质中均蓄积HA，肿瘤细胞中CD44表达显著降低。
我们的结果表明，肿瘤细胞中CD44表达降低可能导致黏液样DF中以HA异常蓄积为特征的间质黏液样改变。
