宫颈癌患者循环DNA的定量及意义

Analysis of circulating DNA level in the plasma of cervical cancer patients

目的检测宫颈癌患者血浆游离DNA含量并探讨其与临床病理特征之间的关系。方法收集42例宫颈癌、20例CINIII患者和20例健康妇女的外周血。用微量基因组提取试剂盒提取血浆DNA,用双链DNA高敏试剂盒和荧光仪测定血浆DNA含量。结果I期宫颈癌患者的血浆DNA水平为(12.78±5.58)ng/ml,明显高于正常组[(7.60±3.87)ng/ml]和CINIII组[(8.10±3.06)ng/ml],P=0.001;II-III期患者的血浆DNA水平为(17.99±7.81)ng/ml,明显高于I期患者,P=0.02;CINIII患者的血浆DNA水平与正常对照者之间无明显差别(P>0.05)。以正常对照者血浆DNA水平的95%可信区间上限15.70 ng/ml为界值,其诊断的敏感性为38.10%,特异性为92.50%,阳性预测值为84.21%,阴性预测值为58.73%。结论宫颈癌患者的血浆DNA水平与疾病的发生、发展密切相关,血浆DNA水平可能有助于宫颈癌的鉴别诊断。

Objective To determine the plasma DNA level and investigate its clinicopathological significance in women with cervical cancers. Methods Blood samples were collected from 42 cervical cancer patients, 20 patients with cervical intraepithelial neoplasia grade Ⅲ（CINⅢ） and 20 healthy women. The plasma DNA was extracted using a commercial kit and detected by a fluorescentmeter. Results The mean plasma DNA level in stage Ⅰ cervical cancer patients was 12.78±5.58 ng/ml, significantly higher than that in CINⅢ patients （8.10±3.06 ng/ml） and normal controls （7.60±3.87 ng/ml） （P=-0.001）. The mean DNA level in stage Ⅱ-Ⅲ patients was 17.99±7.81 ng/ml, significantly higher than that in stage Ⅰ patients （P=-0.02）. No significant difference was found in plasma DNA level between CINⅢ patients and the normal controls （P〉0.05）. When the cut-off for diagnosis of cervical cancer was 15.70 ng/ml, the sensitivity, specificity, positive predictive value and negative predictive value were 38.10%, 92.50%, 84.21% and 58.73%, respectively. Conclusion Plasma DNA level is closely related with malignant transformation and development of cervical cancer, and may become a useful means for differential diagnosis of cervical cancer.