Actis A B, Lampe P D, Eynard A R
Instituto de Biología Celular, Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Casilla de Correos No, 220, Argentina.
Oral Oncol. 2002 Jul;38(5):441-9. doi: 10.1016/s1368-8375(01)00091-4.
Cell proliferation and apoptosis as well as cell-cell adhesion and communication are essential processes that assure cell survival, renewal and coordination. Since junctional proteins have a tumor suppressor activity, their immunohistochemical characterization has diagnostic and prognostic value. The purpose of this report is to review the role played by junctional and proliferation-related proteins in the salivary glands and to illustrate their immunohistochemical localisation in normal murine submandibular gland. Normal salivary gland tissue was obtained from normal adult male BALB/c mice. After immediate fixation in formalin and ethanol, the samples were immunohistochemically stained for E-cadherin (HECD-1), Bcl-2, Ki67 (MIB-1), connexin26 and connexin 32, beta-catenin and gamma-catenin. Their topological distribution and reactivity were evaluated by light microscopy. The nuclei of submandibular acinar cells exhibited low to moderate staining for Ki67, but no reaction was observed in ductal cells. Murine Bcl-2 was light to moderately expressed in the latero-basal domain of cells of submandibular acini but was only lightly expressed in striated and eosinophilic ducts. The lateral domain of acinar cells were heavily stained with anti-E-cadherin, while only low levels were expressed at the cellular surface of ducts. beta-Catenin was consistently and evenly distributed along the latero-apical boundaries of eosinophilic secretory duct cells as well as on the lateral domain of acinar cells. On the contrary, gamma-catenin was generally expressed at lower levels than beta-catenin, was not expressed in ductal cells and was only lightly stained on the lateral membranes of acinar cells. No expression of connexin 32 was observed in ducts but it was significantly expressed in a spotted pattern along the plasma membrane of acinic cells. Connexin 26 showed similar localization to that of connexin 32 but the staining was much more intense. Since these proteins have been reported to play key roles in maintaining homeostasis via control of cell growth, differentiation and death, their analysis in normal salivary tissue will hopefully contribute to the study of salivary tumorigenesis.
细胞增殖与凋亡以及细胞间黏附与通讯是确保细胞存活、更新与协调的重要过程。由于连接蛋白具有肿瘤抑制活性，其免疫组织化学特征具有诊断和预后价值。本报告的目的是综述连接蛋白和增殖相关蛋白在唾液腺中的作用，并阐述它们在正常小鼠下颌下腺中的免疫组织化学定位。正常唾液腺组织取自正常成年雄性BALB/c小鼠。在立即用福尔马林和乙醇固定后，样本进行免疫组织化学染色，检测E-钙黏蛋白（HECD-1）、Bcl-2、Ki67（MIB-1）、连接蛋白26和连接蛋白32、β-连环蛋白和γ-连环蛋白。通过光学显微镜评估它们的拓扑分布和反应性。下颌下腺腺泡细胞的细胞核对Ki67呈低至中度染色，但在导管细胞中未观察到反应。小鼠Bcl-2在下颌下腺腺泡细胞的侧基区域轻度至中度表达，但在纹状管和嗜酸性导管中仅轻度表达。腺泡细胞的外侧区域用抗E-钙黏蛋白染色强烈，而在导管细胞表面仅低水平表达。β-连环蛋白沿嗜酸性分泌导管细胞的侧顶边界以及腺泡细胞的外侧区域持续且均匀分布。相反，γ-连环蛋白的表达水平通常低于β-连环蛋白，在导管细胞中不表达，仅在腺泡细胞的外侧膜上轻度染色。在导管中未观察到连接蛋白32的表达，但在腺泡细胞的质膜上呈斑点状显著表达。连接蛋白26的定位与连接蛋白32相似，但染色要强得多。由于这些蛋白据报道通过控制细胞生长、分化和死亡在维持内环境稳定中起关键作用，对正常唾液组织中它们的分析有望有助于唾液肿瘤发生的研究。
