直接荧光定量法检测肺癌患者血浆游离DNA含量临床意义

Analysis of plasma free DNA level in lung cancer patients by direct fluorescent staining

目的探讨荧光染料直接染色法检测血浆游离DNA含量在肺癌诊断和预后判断中的意义。方法用picogreen荧光染料直接染色法测定不同浓度的人基因组DNA之吸光度,并依此制作标准曲线;收集27例肺癌患者(小细胞肺癌9例,非小细胞肺癌18例)和37例健康体检者新鲜血浆,用picogreen荧光染料直接染色法对血浆游离DNA进行染色,与标准曲线对比得出其含量。结果正常对照组血浆DNA水平(14.1±3.8)μg/L,肺癌组血浆DNA水平15.3μg/L^1771.2μg/L;18例非小细胞肺癌血浆DNA水平15.3μg/L^219.7μg/L,9例小细胞肺癌为68.5μg/L^1771.2μg/L。秩和检验显示:肺癌组明显高于正常对照组(P<0.05);小细胞肺癌组和非小细胞肺癌组之间也有显著性差异(P<0.05);小细胞肺癌伴转移组高于非转移组(P<0.05)。结论肺癌患者血浆游离DNA水平与疾病的发生、发展和预后密切相关,检测血浆DNA水平有助于肺癌的诊断和预后判断。

Objective To discuss the clinical significance of plasma free DNA level in diagnosis and prognosis of lung cancer. Methods The fresh plasma samples were collected from 27 lung cancer patients, including 9 cases of small cell lung cancer and 18 non - small cell lung cancer patients, and 37 healthy controls for direct staining on free DNA using picogreen fluorescent dye, and the standard curves of these plasma samples were drew based on the fluorescent picogreen absorbance, then the stand- ard curves were compared to obtain the DNA levels. Results The plasma DNA levels in lung cancer cases （ 15.3 μg/L - 1771.2 μg/L） were significantly higher than those of healthy controls [ （14.1± 3.8） μg/L], showing significant statistical difference（ P 〈 0. 05 ）. The plasma DNA levels in small cell lung cancer cases（68.5 μg/L - 1771.2 μg/L） were higher than those in non -small cell lung cancer patients（ 15.3 μg/L -219.7 μg/L）, and the difference had statistical significance too（ P 〈 0.05 ）. In addition, there was also statistical difference in the plasma DNA level between small cell lung cancer patients with and without metastasis（P 〈 0.05 ）. Conclusion Plasma free DNA level is closely related with the Occurrence, development and prognosis of lung cancer, and it can contribute to differential diagnosis and prognosis evaluation of lung cancer.