鼻咽癌切除术后患者血浆DNA的快速变化

The level of plasma EBV DNA after surgical resection of nasopharyngeal carcinoma

目的 监测鼻咽癌病人于肿瘤切除手术期间和术后 ,其血浆DNA浓度的变化 ,以了解血浆DNA在体内的动态变化情况。方法 静脉抗凝血分离血浆 ,从血浆中提取DNA ,用实时定量PCR方法分别测定手术前、后鼻咽癌病人血浆DNA的浓度。结果 肿瘤手术初期 ,病人血浆DNA的浓度会快速升高 ,随后其水平会迅速下降 ,DNA在血浆中的半衰期为 12 6min ;当血浆DNA水平降到最低时 ,其水平又会再次升高 ,至 2 385min后出现第二个峰值。结论 癌症病人游离DNA可以极其迅速地从血循环中被清除 ,第二个峰值的水平可能对评估组织损伤严重程度具有一定的临床意义 。

Plasma DNA has now been increasingly utilized for the diagnosis and monitoring of cancers. Previously we have demonstrated that the level of plasma EBV DNA actually reflects the burden of tumor cells in patients with nasopharyngeal carcinoma (NPC). However, little has been know about mechanism and kinetics of the clearance of DNA molecules once they are released into the circulation. In this study, we monitored the levels of plasma DNA (( globin gene) in NPC patients during and after surgical resection of NPC. We were able to show that plasma DNA levels would rise rapidly shortly after the start of the operation and followed by an exponential drop with a median half life of 126 minutes.After reaching the trough levels, plasma DNA concentrations climbed up again and the second peak levels occurred after a median of 2385 minutes.