Tunio G M, Hirota S, Nomura S, Kitamura Y
Department of Pathology, Osaka University Medical School, Suita, Japan.
Arch Pathol Lab Med. 1998 Dec;122(12):1087-90.
Psammoma bodies are often observed in papillary carcinomas of the thyroid. Recently we reported that osteopontin (OPN) appears to play an important role in the development of psammoma bodies in meningiomas. Because the morphology and components of psammoma bodies in papillary carcinoma of the thyroid are similar to those of psammoma bodies in meningioma, we examined whether OPN was related to the psammoma bodies in papillary carcinoma of the thyroid.
Expression of OPN mRNA was examined by Northern blotting and in situ hybridization. Immunohistochemistry was performed to localize the deposition of OPN protein and to identify the type of OPN mRNA-expressing cells.
The expression of OPN mRNA was detected in papillary thyroid carcinomas but not in normal thyroid tissue. Osteopontin mRNA-expressing cells were present around the psammoma bodies, and the localization of OPN protein was consistent with that of psammoma bodies. The OPN mRNA-expressing cells were identified as CD68-positive macrophages.
Osteopontin produced by macrophages may play a significant role in the development of psammoma bodies in papillary carcinoma of the thyroid.
砂粒体常见于甲状腺乳头状癌中。最近我们报道骨桥蛋白（OPN）似乎在脑膜瘤砂粒体的形成中起重要作用。由于甲状腺乳头状癌中砂粒体的形态和成分与脑膜瘤中的砂粒体相似，我们研究了OPN是否与甲状腺乳头状癌中的砂粒体有关。
采用Northern印迹法和原位杂交法检测OPN mRNA的表达。进行免疫组织化学以定位OPN蛋白的沉积并鉴定表达OPN mRNA的细胞类型。
在甲状腺乳头状癌中检测到OPN mRNA的表达，但在正常甲状腺组织中未检测到。表达骨桥蛋白mRNA的细胞存在于砂粒体周围，OPN蛋白的定位与砂粒体一致。表达OPN mRNA的细胞被鉴定为CD68阳性巨噬细胞。
巨噬细胞产生的骨桥蛋白可能在甲状腺乳头状癌砂粒体的形成中起重要作用。
