Mateus Gláucia Cardoso Paixão, Lanza Gleyson Henrique dos Santos Pena, de Moura Pedro Henrique Ribeiro, Marigo Helenice de Andrade, Horta Martinho Campolina Rebello
Oral Pathology Laboratory, School of Dentistry, Pontifícia Universidade Católica de Minas Gerais, Belo Horizonte, MG, Brazil.
Med Oral Patol Oral Cir Bucal. 2008 Nov 1;13(11):E697-702.
Keratocystic odontogenic tumors (KOTs), also known as odontogenic keratocysts, were recently classified as a benign neoplasia due to the aggressive clinical behavior. Although several studies have shown the high proliferative activity of the epithelial lining, few studies have evaluated apoptosis in KOTs. Therefore, the aim of this study is to evaluate and compare the proliferation index (PI) and the apoptotic index (AI) of the epithelial lining in sporadic KOTs, KOTs associated with the Nevoid Basal Cell Carcinoma Syndrome (NBCCS KOTs), and dentigerous cysts.
A total of 11 sporadic KOTs, 15 NBCCS KOTs, and 11 dentigerous cysts were evaluated. The PI was assessed by immunohistochemical detection of the cell proliferation marker Ki-67. The AI was assessed by morphological evaluation of sections stained by methyl green-pyronin. The TUNEL assay was used to confirm the occurrence of apoptosis. Differences in the PI and the AI between sporadic KOTs, NBCCS KOTs, and dentigerous cysts were analyzed using the Kruskal-Wallis test. Differences in the PI and the AI between the epithelial layers of each lesion were analyzed using the Wilcoxon test.
The PI and AI were higher in sporadic and NBCCS KOTs than in dentigerous cysts. No difference in these indexes was observed between sporadic and NBCCS KOTs. In dentigerous cysts, the PI was higher in the basal layer. In sporadic and NBCCS KOTs, the PI was higher in suprabasal layer. No difference in the AI was observed between the basal layer and the suprabasal layer in the three lesions. The AI was higher in the superficial layer of sporadic and NBCCS KOTs.
The present study demonstrates that the epithelial lining of KOTs shows a distinct pattern of cell proliferation and apoptosis, reflecting its high cell turnover and reinforcing its classification as an odontogenic tumor.
角化囊性牙源性肿瘤（KOTs），也称为牙源性角化囊肿，因其侵袭性临床行为最近被归类为良性肿瘤。尽管多项研究表明其上皮衬里具有高增殖活性，但很少有研究评估KOTs中的细胞凋亡情况。因此，本研究的目的是评估和比较散发性KOTs、与痣样基底细胞癌综合征相关的KOTs（NBCCS KOTs）以及含牙囊肿中上皮衬里的增殖指数（PI）和凋亡指数（AI）。
共评估了11例散发性KOTs、15例NBCCS KOTs和11例含牙囊肿。通过免疫组织化学检测细胞增殖标志物Ki-67来评估PI。通过对甲基绿-派洛宁染色切片进行形态学评估来评估AI。采用TUNEL法确认细胞凋亡的发生。使用Kruskal-Wallis检验分析散发性KOTs、NBCCS KOTs和含牙囊肿之间PI和AI的差异。使用Wilcoxon检验分析每个病变上皮层之间PI和AI的差异。
散发性和NBCCS KOTs中的PI和AI高于含牙囊肿。散发性和NBCCS KOTs之间在这些指标上未观察到差异。在含牙囊肿中，基底层的PI较高。在散发性和NBCCS KOTs中，基底上层的PI较高。在这三种病变的基底层和基底上层之间未观察到AI的差异。散发性和NBCCS KOTs表层的AI较高。
本研究表明，KOTs的上皮衬里显示出独特的细胞增殖和凋亡模式，反映了其高细胞更新率，并强化了其作为牙源性肿瘤的分类。
