Fullen Douglas R, Garrisi Angela J, Sanders Donita, Thomas Dafydd
Department of Pathology, Universityof Michigan Medical Center, Ann Arbor, Michigan, USA.
J Cutan Pathol. 2008 Nov;35 Suppl 2:28-34. doi: 10.1111/j.1600-0560.2007.00866.x. Epub 2008 Jan 14.
S100A6, a calcium-binding protein in the S100 family, has been observed in melanocytic nevi, neural tumors, fibrohistiocytic tumors and is overexpressed in melanoma. Previous studies reported S100A6 expression in atypical fibroxanthomas (AFX) but not in a small number of desmoplastic melanomas (DM). Limited data on S100A6 expression in cutaneous epithelial tumors exists in the literature. The goal of this study was to determine the specificity and sensitivity of S100A6 protein in a spectrum of cutaneous mesenchymal or epithelial tumors.
Tissue microarrays of cutaneous epithelial neoplasms, mesenchymal neoplasms, DM and malignant peripheral nerve sheath tumors (MPNST) were stained with S100A6 antibody.
Eleven basal cell carcinomas (BCC) failed to express S100A6, whereas all 10 squamous cell carcinomas (SCC) expressed S100A6. Four of seven microcystic adnexal carcinomas (MAC) stained for S100A6. Tumors with duct differentiation variously expressed S100A6 protein, with two hidradenomas showing the strongest staining. Malignant spindle cell tumors, with the exception of 13 of 30 MPNST, had a high incidence of S100A6 positivity.
S100A6 expression may distinguish SCC from BCC, MAC from BCC and hidradenoma from other adnexal tumors. S100A6 expression favors DM over MPNST but overlap limits its diagnostic use.
S100A6是S100家族中的一种钙结合蛋白，已在黑素细胞痣、神经肿瘤、纤维组织细胞瘤中被观察到，且在黑色素瘤中过表达。先前的研究报道了S100A6在非典型纤维黄色瘤（AFX）中的表达，但在少数促纤维增生性黑色素瘤（DM）中未观察到。文献中关于S100A6在皮肤上皮肿瘤中表达的数据有限。本研究的目的是确定S100A6蛋白在一系列皮肤间叶性或上皮性肿瘤中的特异性和敏感性。
用S100A6抗体对皮肤上皮肿瘤、间叶性肿瘤、DM和恶性周围神经鞘瘤（MPNST）的组织芯片进行染色。
11例基底细胞癌（BCC）未表达S100A6，而所有10例鳞状细胞癌（SCC）均表达S100A6。7例微囊性附属器癌（MAC）中有4例S100A6染色阳性。具有导管分化的肿瘤S100A6蛋白表达各异，2例汗腺腺瘤染色最强。除30例MPNST中有13例外，恶性梭形细胞瘤S100A6阳性率较高。
S100A6表达可区分SCC与BCC、MAC与BCC以及汗腺腺瘤与其他附属器肿瘤。S100A6表达支持DM而非MPNST，但存在重叠限制了其诊断用途。
