Sox10 Is a Novel Marker of Acinus and Intercalated Duct Differentiation in Salivary Gland Tumors
Rie Ohtomo, Taisuke Mori, Koji Tsuta, Akiko M Maeshima, Seiichi Yoshimoto, Masao Asai, Hitoshi Tsuda. National Cancer Center Hospital, Tokyo, Japan
Background: Sox10 is known as a transcription factor crucial for specification and maturation of the neural crest, and maintenance of Schwann cells and melanocytes. In a murine model, Sox10 is also shown to be highly expressed in myoepithelial and acinic cells at the salivary glands. However, there are few reports that studied Sox10 expression in human salivary glands and tumors.
Design: We collected formalin-fixed paraffin-embedded specimens of 15 unremarkable salivary gland tissues (12 parotid glands and 3 submandibular glands) and 15 tumor tissues resected surgically between 1998 and 2010. These tumors comprised of 5 acinic cell carcinomas (AciCC), 3 adenoid cystic carcinoma (ACC), and one case each of epithelial-myoepithelial carcinoma (EMC), salivary duct carcinoma (SDC), mucoepidermoid carcinoma (MEC), carcinoma ex pleomorphic adenoma (Ca-Ex-PA), carcinoma not otherwise specified (CaNOS), pleomorphic adenoma (PA), myoepithelioma (ME). The expression of Sox10, p63 and SMA were immunohistochemically examined and correlated with all types of these salivary glands and tumors.
Results: In all 15 unremarkable salivary glands, Sox10 was expressed in the nuclei of most (>80%) of the myoepithelial cells and luminal (epithelial) cells in acini and intercalated ducts, but not expressed in basal cells and luminal cells of striated and excretory ducts. p63 was confirmed to be expressed in myoepithelial and basal cells but not in all luminal cells, and SMA was confirmed to be expressed only in myoepithelial cells. And Sox10 was expressed luminal and myoepithelial cells of all cases of AciCC, ACC, EMC, and PA, but was completely negative in the cases of SDC, MEC, and CaNOS. In a ME, Sox10 was expressed in myoepithelial cells.
Conclusions: Sox10 was expressed in most of the luminal and abluminal cells of acini and intercalated ducts in all human salivary glands examined. In the salivary tumors, Sox10 was positive in tumors that have similarity to acinus or intercalated duct, i.e. AciCCs, ACCs, EMC, and ME, but negative in those that have similarity to striated and excretory duct, i.e., SDC and MEC. Sox10 can be one of useful markers for the identification of cellular genealogy and diagnosis of salivary gland tumors.
Category: Head & Neck
Tuesday, March 20, 2012 1:00 PM
Poster Session IV # 157, Tuesday Afternoon