肺腺癌中SPG20基因甲基化检测及临床意义

The Clinical Significance of Detection of SPG20 Gene Methylation in Lung Adenocarcinoma

目的 探讨肺腺癌组织中痉挛性截瘫20(SPG20)基因甲基化与临床病理的关系。方法 通过焦磷酸测序法检测70例肺腺癌组织和正常肺组织中SPG20基因甲基化程度,实时荧光定量PCR(qRT-PCR)法检测SPG20 mRNA相对表达量,免疫组化和Western blot检测SPG20蛋白表达量,分析SPG20甲基化程度与蛋白表达及患者临床病理特征之间的关系。结果 肺腺癌组织中SPG20甲基化率(68.57%)高于正常肺组织(18.57%)(P<0.05),SPG20 mRNA表达水平(1.22±0.47)低于正常肺组织(5.79±1.13)(P<0.05)。免疫组化结果显示,肺腺癌组织中SPG20蛋白表达阳性率(24.29%)低于正常肺组织(68.57%)(P<0.05)。Western blot结果显示,肺腺癌组织中SPG20蛋白表达(15.78±1.85)%低于正常肺组织(63.14±2.05)%(P <0.05)。SPG20蛋白表达量与其甲基化程度呈负相关(r=-0.457,P<0.05)。肺腺癌组织中SPG20甲基化水平与患者的TNM分期、组织分化和淋巴结转移密切相关(P<0.05)。结论 SPG20高甲基化状态与肺腺癌的发生发展相关。

Objective To investigate the relationship between spastic paraplegia 20(SPG20) gene methylation and clinicopathology in lung adenocarcinoma tissue. Methods The degree of gene methylation in 70 lung adenocarcinoma tissues and normal lung tissues was detected by pyrophosphate sequencing method. The m RNA relative expression of SPG20 in tissues was detected by quantitative real-time fluorescence PCR(q RT-PCR).The protein expression of SPG20 was detected by Immunohistochemical method and Western blot. The relationship between SPG20 degree of methylation and clinicopathological characteristics of patients was analyzed. Results The SPG20 methylation rate was 68.57% in cancer tissues,higher than 18.57% in normal lung tissues(P<0.05),and the expression level of SPG20 m RNA in cancer tissues(1.22±0.47)was lower than that in normal lung tissues(5.79±1.13)(P<0.05). Immunohistochemistry showed that the positive rate of SPG20 protein expression in cancer tissues was 24.29%,lower than 68.57% of normal lung tissues(P<0.05).The Western blot results showed that the protein expression of SPG20 was(15.78±1.85)% in cancer tissues,lower than that in normal lung tissues significantly(63.14±2.05)%(P<0.05). SPG20 protein expression was negative correlated with the SPG20 methylation(r=-0.457,P<0.05). The level of SPG20 methylation in lung adenocarcinoma tissues was closely related to TNM staging,tissue differentiation and lymph node metastasis(P<0.05). Conclusion The SPG20 hypermethylation status is associated with the occurrence and development of lung adenocarcinoma.