目的:探讨循环血中Shope病毒DNA含量与兔VX2肿瘤18F-FDGPET/CT影像学特征间的关系及其临床意义。方法:采用组织块接种法建立兔VX2肿瘤模型,并行18^F-FDGPET-CT观测肿瘤大小及糖代谢相关值,实时定量荧光探针PCR法检测肿瘤组织及血浆中Shope病毒特征性DNA片段含量。结果:移植前外周血中未检测出Shope病毒特异性DNA片段;移植后2周,VX2肿瘤组织和循环血中均可以检测到特征性Shope病毒DNA片段。瘤体内DNA含量明显高于循环血中含量。循环血Shope病毒DNA含量与FDG-PET的最大标准摄取值(SUVmax)明显呈正相关(r=0.943,p=0.005),但与肿瘤体积相关性尚不明确(r=0.657,p=0.156)。结论:循环血Shope病毒DNA有望作为一种潜在的VX2肿瘤标志物,其廉价、无创的特性,有望在肿瘤的早期诊断和预后随访中发挥优势。
Objective: To investigate the relationship between 18F-FDG PET/CT imaging characteristics and circulating cell-free shope virus DNA copies, and to explore its clinical values. Methods: The VX2 tumor models in rabbit were established by transplanting VX2 tumor mass into leg muscles, and the shope virus DNA in tumor tissues and plasma was quantified by a quantitative real-time quantitative polymerase chain reaction (PCR) method. Results: Before tumor transplantation, no viral DNA was detected in peripheral blood; 14 days after transplantation circulating shope virus specific DNA fragments could be detected. Concentration of shope virus DNA in tumor tissue (mean (4.9± 1.9)× 10^6 copies/L) was significantly higher than that in the plasma (mean (1.3± 0.9)× 10^3 copies/L). There is a positive association between circulating shope DNA level and 18F-FDG-PET/CT maximum standard uptake value, but no significant association was observed between plasma shope virus DNA level and VX2 tumor size. Conclusion: Cell-free shope viral DNA in circulating plasma may be a tumor-marker of VX2 tumor animal model for cancer research, and circulating cell free tumor specific DNA may be proposed as a novel and early detectable bio-marker as well as an inexpensive and noninvasive assay for cancer management.