抑癌基因CX26在喉鳞状细胞癌中的表达及临床意义

The expressions and clinical significance of tumor suppressor gene CX26 in laryngeal squamous cell carcinoma

目的:观察抑癌基因CX26的mRNA和蛋白质在喉鳞状细胞癌中的表达情况,探讨CX26基因与喉鳞状细胞癌生物学行为的关系,及其与喉鳞状细胞癌发生和发展的分子机制。方法:38例喉鳞状细胞癌患者,每例患者均同时在喉癌切除手术时从喉癌肿瘤组织中心部位取癌组织(喉癌组),在肿瘤边缘外1.0cm部位取喉癌旁组织(对照组),分别采用半定量RT-PCR检测CX26mRNA的表达水平,冷冻切片免疫组织化学方法检测CX26蛋白的表达情况。结果:RT-PCR结果显示,CX26mRNA在喉癌组和对照组中均呈阳性表达;经半定量分析,CX26mRNA在喉癌组中的表达较对照组明显降低(P<0.05);免疫组织化学发现,CX26蛋白在18例(47.4%)患者的喉癌组织呈阳性表达,在34例(89.5%)患者的喉癌旁组织呈强阳性表达,CX26蛋白在两者中的阳性表达差异有统计学意义(P<0.05),并且伴有细胞内定位的改变;同时发现,CX26蛋白阳性表达率和CX26基因mRNA的表达水平在Ⅲ期和Ⅳ期喉癌组明显低于Ⅰ期和Ⅱ期(P<0.05),有颈淋巴结转移者明显低于无转移者(P<0.05),并且其表达水平随病理分化程度的降低而降低(P<0.05)。结论:CX26与喉癌的发生和发展关系密切,并可能与喉癌的预后有关。

Objective：To investigate the expressions of tumor suppressor gene CX26 mRNA and coding protein in laryngeal squamous cell carcinoma, and to explore the relationship between CX26 gene and the biological behaviors of laryngeal squamous cell carcinoma for understanding the tumorigenicity and development of laryngeal squamous cell carcinoma. Method：Laryngeal carcinoma tissues （studying group）, which taked from the center of tumors and laryngeal normal tissues （control group）raked at the place of 1.0 cm out of the edge of the tumors, were took from 38 patients with laryngeal squamous cell carcinoma while they were in operation. Semi quantitative reverse transcriptase polymerase chain reaction （RT-PCR） was used to analyze the expression level of CX26 mR- NA, and immunohistochemical staining （frozen section） was used to detect the expression of CX26 protein in laryngeal carcinoma tissues and laryngeal normal tissues of 38 cases, respectively. Result：mRNA of CX26 gene was all positively expressed in laryngeal carcinoma tissues and laryngeal normal tissues of 38 cases by RT-PCR. However, CX26mRNA was obviously down regulated in laryngeal carcinoma tissues than that in laryngeal normal tissues （P〈0. 05）. Immunohistochemieal staining showed CX26 protein was strong-positively expressed in laryngeal normal tissues in 34 cases （89.5%）, while it was positively expressed in laryngeal carcinoma tissues in 18 cases （47.4%）, and with the location alteration of CX26 protein in laryngeal carcinoma cells. There was significant difference between the expression rate of CX26 protein in laryngeal carcinoma tissues and in laryngeal normal tissues（P〈0.05）. Meanwhile, the expression level of CX26 mRNA and the positive-expressed rate of CX26 protein of the laryngeal carcinoma tissues in the advanced stage patients group （Ⅲ stage and Ⅳ stage） were significantly lower than these in the early stage patients group （ Ⅰ and Ⅱ） （P〈0.05）, and it was significantly lower in those who have a cervical lymph node metastasis than those without metastasis. （P〈0.05）. Moreover, the expression level of CX26 mRNA and the positive-expressed rate of CX26 protein reduced along with the reduction of pathological differentiation , and there was significant difference among the well differentiated group, moderately-differ- entiated group and poorly-differentiated group（P〈0.05）. Conclusion：CX26 gene may play an important role in the pathogenisis and development of laryngeal carcinoma and may be related to its prognosis.