宫颈癌患者循环DNA的定量及意义

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.

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

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.