Department of Obstetrics and Gynecology, Kanazawa University Graduate School of Medicine, 13-1 Takaramachi, Kanazawa, Ishikawa 920-8641, Japan.
Br J Cancer. 2012 Jul 24;107(3):448-54. doi: 10.1038/bjc.2012.276. Epub 2012 Jun 26.
Recently developed detection system for circulating tumour cells (CTCs) using a telomerase-specific replicative adenovirus generated nonspecific green fluorescent protein (GFP) signals because of the co-presence of white blood cells (WBCs) nonspecifically infected by viruses. Here, we established a unique detection system for CTCs that completely excludes nonspecific signals.
Blood obtained from the patients was subjected to haemolytic processes to eliminate red blood cells. The cell pellets were then infected with OBP-401, fixed, incubated with fluorescence-labelled anti-CD45 antibody to mark white blood WBCs, and examined on slides under a microscope.
Preparatory experiments with cancer cells artificially added to healthy donor samples confirmed that CD45 labelling could distinguish GFP-positive cancer cells from WBCs. In 53 patients with gynaecological cancers, CTCs were detected in 21 patients (39.6%) when CD45-positive cells were excluded as WBCs among GFP-positive cells. No CTCs were detected in samples from healthy volunteers. There was no significant correlation between CTC counts and known clinicopathological factors. The CTCs rapidly vanished after surgery or chemotherapy in most patients whose treatments were effective. In contrast, the persistence of CTCs even after treatments was tightly associated with poor response to the treatments (P<0.005).
The presence of CTCs in our system may potentially be a novel therapeutic marker in gynaecological cancers.
最近开发的循环肿瘤细胞（CTC）检测系统使用一种端粒酶特异性复制腺病毒，由于白细胞（WBC）被病毒非特异性感染，会产生非特异性绿色荧光蛋白（GFP）信号。在此，我们建立了一种独特的 CTC 检测系统，可完全排除非特异性信号。
从患者获得的血液经过溶血处理以消除红细胞。然后将细胞沉淀用 OBP-401 感染、固定，用荧光标记的抗 CD45 抗体孵育以标记白细胞，然后在显微镜下观察载玻片。
在将癌细胞人工添加到健康供体样本的预备实验中，证实 CD45 标记可区分 GFP 阳性癌细胞和 WBC。在 53 名妇科癌症患者中，当排除 GFP 阳性细胞中的 CD45 阳性细胞作为 WBC 时，在 21 名患者（39.6%）中检测到 CTC。在健康志愿者的样本中未检测到 CTC。CTC 计数与已知的临床病理因素之间没有显著相关性。在大多数治疗有效的患者中，手术后或化疗后 CTC 迅速消失。相比之下，即使在治疗后 CTC 的持续存在也与对治疗的反应不佳密切相关（P<0.005）。
我们系统中 CTC 的存在可能是妇科癌症的一种新的治疗标志物。
