Miyake Tetsumi, Tanaka Yukichi, Kato Keisuke, Tanaka Mio, Sato Yukiko, Ijiri Rieko, Inayama Yoshiaki, Ito Yumi, Aoki Shinjiro, Kawabe Ryoichi, Tohnai Iwai
Department of Oral Maxillofacial Surgery, Yokohama City University Graduate School of Medicine, Yokohama, Japan.
Pathol Int. 2006 Dec;56(12):732-7. doi: 10.1111/j.1440-1827.2006.02039.x.
In the present study the significance of nuclear/cytoplasmic expression of beta-catenin (CTNNB1) and mutation of the CTNNB1 gene (CTNNB1) in odontogenic tumors was examined. Six ameloblastomas (five follicular ameloblastomas and one plexiform ameloblastoma) and three malignant odontogenic tumors (one metastasizing ameloblastoma, one ameloblastic carcinoma, and one primary intraosseous odontogenic carcinoma) were investigated for CTNNB1 expression and CTNNB1 mutation. Immunohistochemically, all follicular ameloblastomas and one primary intraosseous odontogenic carcinoma exhibited focal and moderate nuclear/cytoplasmic expression of CTNNB1, whereas the plexiform ameloblastoma and the remaining two malignant odontogenic tumors had entirely membranous expression. CTNNB1 mutation at codon 40 of exon 3 was found in one of the six follicular ameloblastomas. The other five follicular ameloblastomas, the plexiform ameloblastoma, and the three malignant odontogenic tumors did not show mutation in exon 3 of CTNNB1. These findings further confirmed that CTNNB1 mutation is not frequent in ameloblastoma and malignant odontogenic tumors, although the abnormality of Wnt signaling may be associated with some of these tumors.
在本研究中，检测了β-连环蛋白（CTNNB1）的核/细胞质表达及CTNNB1基因（CTNNB1）突变在牙源性肿瘤中的意义。研究了6例成釉细胞瘤（5例滤泡型成釉细胞瘤和1例丛状成釉细胞瘤）和3例恶性牙源性肿瘤（1例转移性成釉细胞瘤、1例成釉细胞癌和1例原发性骨内牙源性癌）的CTNNB1表达及CTNNB1突变情况。免疫组织化学结果显示，所有滤泡型成釉细胞瘤和1例原发性骨内牙源性癌均表现为CTNNB1的局灶性、中度核/细胞质表达，而丛状成釉细胞瘤和其余2例恶性牙源性肿瘤则完全为膜性表达。在6例滤泡型成釉细胞瘤中的1例发现了第3外显子40密码子处的CTNNB1突变。其余5例滤泡型成釉细胞瘤、丛状成釉细胞瘤和3例恶性牙源性肿瘤在CTNNB1的第3外显子未显示突变。这些发现进一步证实，尽管Wnt信号异常可能与部分此类肿瘤有关，但CTNNB1突变在成釉细胞瘤和恶性牙源性肿瘤中并不常见。
