de Araújo Vera Cavalcanti, Furuse Cristiane, Cury Patricia Ramos, Altemani Albina, de Araújo Ney Soares
Department of Oral Pathology, São Leopoldo Mandic Dental Research Center, Rua José Rocha Junqueira 13, Campinas-SP 13045-755, Brazil.
Oral Oncol. 2008 May;44(5):439-45. doi: 10.1016/j.oraloncology.2007.05.011. Epub 2007 Sep 7.
The aim of the present study was to evaluate the signal transducer and activator of transcription (STAT3) expression, which is constitutively active in different types of malignant tumours, in salivary gland tumours. Fifty biopsies of salivary gland tumours (9 pleomorphic adenomas, 12 adenoid cystic carcinomas, 7 epithelial-myoepithelial carcinomas, 10 polymorphous low-grade adenocarcinomas and 12 mucoepidermoid carcinomas) and 10 normal salivary glands were immunohistochemically labeled for STAT3 and Phospho-STAT3 (STAT3P). The labeled sections were qualitatively and quantitatively evaluated. The results showed that, in normal salivary gland, STAT3 was expressed in cytoplasm and STAT3P in nuclei of all tissue cells, except in large mucous acinar cells for which both antibodies were negative. In pleomorphic adenoma, the expression was the same as in normal glands. In malignant tumours, there were variations in the expression of these antibodies. The most important one was the presence of STAT3 in the nuclei of the malignant tumour cells, most evident in the cribriform-type of adenoid cystic carcinoma. Both loss and variation of STAT3P expression were also observed. The presence of STAT3 in the nuclei of malignant salivary gland tumours may represent an important event in oncogenesis probably contributing to tumour cell proliferation while blocking apoptosis. However, further investigation will be necessary to support this hypothesis.
本研究的目的是评估信号转导子和转录激活子（STAT3）的表达情况，STAT3在不同类型的恶性肿瘤中具有组成性活性，此次研究聚焦于唾液腺肿瘤。对50例唾液腺肿瘤活检组织（9例多形性腺瘤、12例腺样囊性癌、7例上皮-肌上皮癌、10例多形性低度腺癌和12例黏液表皮样癌）以及10例正常唾液腺进行免疫组织化学标记，检测STAT3和磷酸化STAT3（STAT3P）。对标记后的切片进行定性和定量评估。结果显示，在正常唾液腺中，STAT3表达于所有组织细胞的细胞质中，STAT3P表达于细胞核中，但大黏液腺泡细胞除外，这两种抗体对其均呈阴性。在多形性腺瘤中，其表达与正常腺体相同。在恶性肿瘤中，这些抗体的表达存在差异。最重要的是，在恶性肿瘤细胞的细胞核中存在STAT3，在筛状型腺样囊性癌中最为明显。还观察到STAT3P表达的缺失和变化。恶性唾液腺肿瘤细胞核中STAT3的存在可能代表肿瘤发生过程中的一个重要事件，可能有助于肿瘤细胞增殖，同时抑制细胞凋亡。然而，需要进一步研究来支持这一假说。
