Obermayr Eva, Bednarz-Knoll Natalia, Orsetti Beatrice, Weier Heinz-Ulrich, Lambrechts Sandrina, Castillo-Tong Dan Cacsire, Reinthaller Alexander, Braicu Elena Ioana, Mahner Sven, Sehouli Jalid, Vergote Ignace, Theillet Charles, Zeillinger Robert, Brandt Burkhard
Department of Obstetrics and Gynecology, Medical University of Vienna, Vienna, Austria.
Institute of Tumor Biology, University Medical Center Eppendorf, Hamburg, Germany.
Oncotarget. 2017 Nov 16;8(63):106415-106428. doi: 10.18632/oncotarget.22468. eCollection 2017 Dec 5.
In 75% of ovarian cancer patients the tumor mass is completely eradicated by established surgical and cytotoxic treatment; however, the majority of the tumors recur within 24 months. Here we investigated the role of circulating tumor cells (CTCs) indicating occult tumor load, which remains inaccessible by established diagnostics.
Blood was taken at diagnosis (baseline samples, = 102) and six months after completion of adjuvant first-line chemotherapy (follow-up samples; = 78). CTCs were enriched by density gradient centrifugation. A multi-marker immunostaining was established and further complemented by FISH on CTCs and tumor/metastasis tissues using probes for stem-cell like fusion genes MECOM and HHLA1.
CTCs were observed in 26.5% baseline and 7.7% follow-up blood samples at a mean number of 12.4 and 2.8 CTCs per ml blood, respectively. Baseline CTCs indicated a higher risk of death in R0 patients with complete gross resection (univariate: HR 2.158, 95% CI 1.111-4.191, = 0.023; multivariate: HR 2.720, 95% CI 1.340-5.522, = 0.006). At follow-up, the presence of CTCs was associated with response to primary treatment as assessed using RECIST criteria. Chromosomal gains at MECOM and HHLA1 loci suggest that the observed cells were cancer cells and reflect pathophysiological decisive chromosomal aberrations of the primary and metastatic tumors.
Our data suggest that CTCs detected by the multi-marker protein panel and/or MECOM/HHLA1 FISH represent minimal residual disease in optimally debulked ovarian cancer patients. The role of CTCs cells especially for clinical therapy stratification of the patients has to be validated in consecutive larger studies applying standardized treatment schemes.
在75%的卵巢癌患者中，肿瘤块可通过既定的手术和细胞毒性治疗被完全清除；然而，大多数肿瘤会在24个月内复发。在此，我们研究了循环肿瘤细胞（CTC）在提示隐匿性肿瘤负荷方面的作用，而既定诊断方法无法检测到这种隐匿性肿瘤负荷。
在诊断时（基线样本，n = 102）以及辅助一线化疗完成后6个月（随访样本；n = 78）采集血液。通过密度梯度离心法富集CTC。建立了多标记免疫染色，并使用针对干细胞样融合基因MECOM和HHLA1的探针，通过荧光原位杂交（FISH）对CTC以及肿瘤/转移组织进行进一步补充检测。
在基线血液样本中，26.5%检测到CTC，平均每毫升血液中有12.4个CTC；在随访血液样本中，7.7%检测到CTC，平均每毫升血液中有2.8个CTC。基线CTC表明，在进行了完全肉眼切除的R0患者中死亡风险更高（单变量：风险比[HR] 2.158，95%置信区间[CI] 1.111 - 4.191，P = 0.023；多变量：HR 2.720，95% CI 1.340 - 5.522，P = 0.006）。在随访时，根据实体瘤疗效评价标准（RECIST）评估，CTC的存在与对初始治疗的反应相关。MECOM和HHLA1基因座处的染色体增益表明，所观察到的细胞是癌细胞，反映了原发性和转移性肿瘤的病理生理决定性染色体畸变。
我们的数据表明，通过多标记蛋白质组和/或MECOM/HHLA1 FISH检测到的CTC代表了最佳减瘤后的卵巢癌患者中的微小残留病。CTC细胞在患者临床治疗分层中的作用，尤其需要在应用标准化治疗方案的连续更大规模研究中进行验证。
