肺癌患者血浆游离性DNA的研究

A study on plasma DNA from patients with lung cancer

目的 研究 (1)肺癌患者血浆游离DNA的肿瘤特异性 ;(2 )肺癌患者血浆游离DNA 3p部位微卫星不稳定 (microsatel liteinstability ,MSI)和杂合性缺失 (lossofheteroxygosity,LOH)在肺癌论断、监测中的意义。方法 本研究以 37例肺癌术后新鲜标本、94例肺癌患者的全血标本作为研究对象 ;15例健康正常人和 15例结核病人的全血标本作为对照。通过PCR 银染法检测血浆游离DNA3p部位 3个微卫星位点的LOH、MSI情况 ;并和组织标本结果进行对比。结果 (1)大多数肺癌患者的血浆游离DNA的浓度在微克水平以上 ,而 15例正常对照和 15例结核病人多在微克水平以下 ;(2 )联合 3个位点进行LOH、MSI检测时 ,组织和血浆的阳性率均在 70 %以上 ,一致性在 80 %以上 ;而对照组未检测到有LOH、MSI;(3)不同分期、不同病理类型的LOH、MSI之间差异无显著性意义 ;(4 )有淋巴结转移与无淋巴结转移之间差异有显著性意义。结论 血浆游离DNA的未可微克含量水平具有一定的诊断意义 ,其 3p部位的微卫星检测在肺癌的诊断中具有较高的敏感性和特异性 ,并和组织标本有较高的一致性变化。肺癌患者血浆游离DNA可以作为基因检测的新途径 。

Objective It aimed to study:(1)the tumor specificity of free plasma DNA.(2)the diagnostic and monitoring value of LOH and MSI of 3p microsatelite point in free plasma DNA of lung cancer patients.Methods we made 37 surgery fresh tissue and whole blood sample from 94 patients as the objects ,whole blood sample from 15 health and 15 Tuberculosis patients as controls,measured the free DNA content of plasma,detected LOH and MSI of three microsatellite sites of plasma DNA on chromosome 3p,and compared with result of tissues.Results (1)The plasma free DNA concentration of most lung cancer patients was above microgramme level and the controls below it.(2)Above 70% of tissues and plasmas were positive,and the concordance was above 80%.No LOH and MSI was found in 15 controls.(3)No significant diffenrence was found on diffencent stages and pathology types.(4)The result of patients with metastasis was significant diffenrent with the patients without metastasis.Conclusion The microgramme level of plasma DNA had a certain extene diagnosi value.Microsatellite analysis on chromosome 3p of plasma DNA has high specifecity sencentivity and value for diagnosis of lung cancer.It is a good medium of gene detection and will be used widespreadedly in future.