DNA甲基转移酶在原发性肺癌患者血清中的表达及临床意义

Expression and significance of DNA methyltransferase in sera of patients with lung cancer

目的观察原发性肺癌患者血清中DNA甲基转移酶（DNMT）1、3a、3b蛋白表达，探讨其临床意义。方法采用酶联免疫吸附试验（ELISA）法对2012年9月至2013年6月郑州大学第一附属医院呼吸内科136例原发性肺癌患者（肺癌组）和同期郑州市第六人民医院进行健康体检的147名健康人群（对照组）血清中DNMT1、3a、3b蛋白表达进行测定，采用Logistic回归分析蛋白表达与肺癌危险性关系及蛋白的表达与肺癌临床病理特征的关系。结果肺癌组DNMTl、DNMT3a、3b蛋白表达（15±10、997±76、302±25）均显著高于对照组（15±10、344±93、1084-22）（t=3．28、62．51、37．27，P=0．021、0．000、0．000）；非条件Logistic回归分析提示DNMTl、3a、3b蛋白高表达均可增加患肺癌的危险性（X2=14．811、26．768、12．057，P=0．000、0．000、0．001），其中DNMTl显著增加患肺癌的危险性（OR=1．545，95％CI：1．238～1．928）。不同组织学类型和不同临床分期肺癌患者的DNMTl、3a、3b蛋白表达差异均无统计学意义（均P〉0．05）。结论血清中DNMTl、5a、3b蛋白高表达可增加患肺癌的危险性，可能是肺癌发展早期过程中的重要生物学标志。

Objective To explore the protein expressions of DNMT1, DNMT3a and DNMT3b in sera of lung cancer patients. Methods Enzyme-linked immunosorbent assay （ELISA） method was used to measure the protein expressions of DNMT1, DNMT3a and DNMT3b in 136 lung cancer patients hospitalized at Department of Respiratory Diseases, First Affiliated Hospital, Zhengzhou University during September 2012 to June 2013. And 147 healthy controls were selected from a population of physical examination at Sixth People＇s Hospital of Zhengzhou. And the relationship was analyzed between protein expressions of DNMT1, DNMT3a and DNMT3b and clinic characteristics of lung cancer. Results The protein expressions of DNMT1, DNMT3a and DNMT3b in patients with lung cancer （ 15 ± 10,997 ± 76 , 302 ±25 ） were higher than those of the controls （13 ± 10, 344 ±93, 108 ±22）. And there were statistical significance （t =3.28, 62. 51, 37.27; P = 0.021, 0.000, 0.000）. The results of Logistic regression show that the protein expressions DNMT1, DNMT3a and DNMT3b increased morbidity for lung cancer （X2 = 14. 811, 26. 768, 12. 057 ; P =0. 000, 0. 000 0. 001 ）, especially so for DNMT1 （ OR = 1. 545,95% CI： 1. 238 - 1. 928）. No correlation existed between the protein expressions of DNMT1, DNMT3a, DNMT3b and histological types or stages （P 〉 0. 05 ）. Conclusions The high protein expressions of serum DNMT1, DNMT3a and DNMT3b increase morbidity for lung cancer. And these markers may predict the early occurrence of lung cancer.