喉癌组织中Klotho基因的表达及其临床意义

Expression of Klotho gene in laryngeal carcinoma and its clinical significance

目的探讨喉癌组织中Klotho基因的表达及其与临床病理特征的关系。方法应用实时荧光定量PCR(QPCR)和Western blotting检测80例喉癌组织及癌旁正常组织中的Klotho mRNA及蛋白表达情况,并探讨两者表达与临床病理特征的关系。采用甲基化特异性PCR(MSP)法检测Klotho基因启动子DNA甲基化状况。结果 80例喉癌组织中的Klotho mRNA相对表达量为0.2890±0.012,低于癌旁正常组织的0.7908±0.015,差异有统计学意义(P<0.01);Klotho蛋白相对表达量为0.2290±0.009,低于癌旁正常组织的0.5368±0.023,差异有统计学意义(P<0.01)。Klotho mRNA及蛋白表达与肿瘤浸润深度及淋巴结转移有关(P<0.05),而与年龄、性别、肿瘤部位、分化程度无关(P>0.05)。喉癌组织及癌旁正常组织中Klotho基因启动子区DNA甲基化率分别为53.8%(43/80)、26.2%(21/80),差异有统计学意义(P<0.05)。结论Klotho基因在喉癌组织中表达下调,其表达可能受Klotho基因启动子区DNA甲基化水平的调控,且与浸润深度及淋巴结转移密切相关。

Objective To explore the expression of Klotho gene in human laryngeal carcinoma tissues and its clinical significance. Methods The expression of Klotho mRNA and protein were measured in 80 paired normal and laryngeal squamous cell carcinoma（ LSCC） tissue samples by real-time fluoresence quntitative polymerase chain reaction（ QPCR） and Western blotting. The relation between Klotho expression and clinical pathological parameters was investigated. Methylation-specific polymerase（ MSP） chain reaction were performed to analyze the DNA methylation of Klotho promoter. Results The expression of Klotho mRNA in LSCC tissues was 0. 2890 ± 0. 012,significantly lower than 0. 7908 ± 0. 015 in corresponding non-malignant tissues（ P〈0. 01）. The expression of Klotho protein in LSCC tissues was 0. 2290 ± 0. 009,significantly lower than 0. 5368 ± 0. 023 in their corresponding non-tumor tissues（P〈0. 01）. The expression of Klotho was related to depth of tumor invasion and lymph node metastasis,but not related to age,sex,tumor location and degree of differentiation（ P〉0. 05）. The DNA methylation rate of Klotho gene promoter region in 80 cases of LSCC and adjacent non-tumor laryngeal tissues was 53. 8%（43/80） and 26. 2%（21/80）,respectively,and the difference was statistically significant（ P〈0. 05）. Conclusion The aberrant DNA methylation of Klotho promoter region may be mainly responsible for its downregulation in LSCC,and plays a key role in invasion and metastasis.