Molecular pathological study of tooth germ and odonto genic tumor

为了阐明上皮和间充质在牙胚分化过程中的相互作用，我们研究了牙胚发育过程中BMP家族基因表达和主要基底膜成分IV型胶原各α链的定位和变化。BMP-4和BMP-7在胎龄11天时表达<th>，BMP-2在胎龄12天时表达<th>。此外，胶原IV的每个α链以阶段依赖的方式定位于牙胚上皮的基底膜。我们研究了BMP家族的作用，以了解牙源性肿瘤细胞的分化。在成釉细胞瘤中，釉原蛋白表达在与早期牙胚形态相似的肿瘤细胞中检测到。在功能分化方面，釉原蛋白在分化晚期表达。在促结缔组织增生性成釉细胞瘤中，BMP家族被证明在基质向牙周组织分化中具有可能的作用。在牙源性腺瘤样瘤中，BMP家族定位与牙胚基质形成阶段相似。综上所述，我们揭示了BMP家族在牙源性肿瘤中各组织类型向实质和间质的诱导分化中的特殊作用，并分析了cbfal在小鼠牙胚基质蛋白表达和骨形成中的作用，揭示了其在牙胚基质蛋白表达和形态形成中的作用。此外，cbaf 1基因敲除小鼠的研究表明，cbfa在切牙牙胚中的分化和转录调控与成骨细胞不同。

To clarify the reciprocal roles of epithelium and mesenchyme in tooth germ differentiation process, we investigated the localization and change of BMP family gene expression and each alpha chain of collagen IV, which is a main basal membrane component, in tooth germ development. The expressions of BMP-4 and BMP-7 at fetal age 11^<th> day and BMP-2 expression at fetal age 12^<th> day were shown. Moreover, each of alpha chains of collagen IV was localized in basal membrane of tooth germ epithelium in a stage dependent manner.We examined the role of BMP family to understand the odontogenic tumor cell differentiation. In ameloblastoma, amelogenin expression was detected in tumor cells with a morphologic similarity to early tooth germ. In terms of functional differentiation, amelogenin was expressed in late differentiation stage. In desmoplastic ameloblastoma, BMP family was shown to have a possible role for the differentiation of stroma into periodontal tissue. In adenomatoid odontogenic tumor, BMP family localization was resembled to matrix formation stage of tooth germ. In summary, we showed the special role of BMP family in induction and differentiation of each tissue type into parenchyma and stroma in odontogenic tumors.Then we analyzed the role of cbfal in matrix protein expression and bone formation in mouse tooth germ and showed its role in matrix protein expression and morphologic formation of tooth germ. Furthermore, cbaf1 knock-out mouse studies demonstrated that differentiation and transcription regulation in incisor tooth germ by cbfa was different than in osteoblasts.