喉癌中线粒体DNA拷贝数和D-loop区基因突变与临床病理的相关性

Correlation between mitochondrial DNA copy number and D-loop gene mutation and clinicopathological features in laryngeal carcinoma

目的探讨喉癌线粒体DNA(mitochondrial DNA,mt DNA)拷贝数和D-loop区基因突变与临床病理特征的相关性。方法收集武汉市第一医院诊治的40例喉癌患者,取mt DNA的CoxⅡ和核DNA的β-actin为目的片段进行实时荧光定量PCR(quantitative real-time PCR,qRT-PCR)扩增,对mt DNA D-loop区进行测序。结果喉癌组织中mt DNA拷贝数(0. 925±0. 136)高于其对应癌旁组织(0. 815±0. 096),两者差异有统计学意义(P <0. 05)。mt DNA拷贝数与患者淋巴结转移相关(P <0. 05),但与患者性别、吸烟、饮酒、肿瘤分期以及肿瘤分化无关。40例喉癌中有21例(52. 50%) mt DNA D-loop区共检测17个突变位点、34个突变;发现86个多态性位点;且mt DNA D-loop区基因突变与患者淋巴结转移和肿瘤分化程度相关(P均<0. 05),其与患者性别、吸烟、饮酒以及肿瘤分期无关。结论喉癌组织中mt DNA拷贝数高于其对应癌旁组织,且mt DNA Dloop区存在高频基因突变,提示mt DNA拷贝数变化以及D-loop区基因突变与喉癌的发生、发展密切相关。

Purpose To investigate the correlation between mitochondrial DNA( mt DNA) copy number and D-loop gene mutation and clinicopathological features in laryngeal carcinoma.Methods 40 cases of laryngeal cancer patients were selected from Wuhan No. 1 Hospital. The quantitative real-time PCR(qRT-PCR) was performed for the mt DNA of Cox Ⅱ and β-actin of nuclear DNA. The mt DNA D-loop region was sequenced.Results The mt DNA copy number(0. 925 ± 0. 136) in laryngeal carcinoma tissue was higher than that in adjacent tissue(0. 815 ± 0. 096),the difference was statistically significant(P< 0. 05). mt DNA copy number was correlated with lymph node metastasis( P < 0. 05),but not with sex,smoking,drinking,tumor stage and tumor differentiation. Of the 40 patients with laryngeal cancer,21( 52. 50%) patients had 17 mutation sites and 34 mutations in the mt DNA D-loop region. A total of 86 polymorphic loci were found. The mt DNA D-loop gene mutationwas associated with lymph node metastasis and tumor differentiation( P < 0. 05),which was not related to gender,smoking,alcohol consumption and tumor stage. Conclusion The mt DNA copy number in laryngeal carcinoma tissue is higher than that in adjacent normal tissue,and there is a high frequency gene mutation in mt DNA D-loop region,which indicates that mt DNA copy number and D-loop gene mutation are closely related to the occurrence and development of laryngeal carcinoma.