Isolation and characterization of circulating tumor cells in patients with metastatic colorectal cancer
Isolation and characterization of circulating tumor cells in patients with metastatic colorectal cancer
复制标题
DOI：
10.3816/ccc.2006.n.029
复制
发表时间：
2006-07-01
影响因子：
3.4
通讯作者：
Meropol, Neal J.
中科院分区：
文献类型：
--
作者：
Cohen, Steven J.;Alpaugh, R. Katherine;Meropol, Neal J.
目的：由于缺乏一种非侵入性的药物效应替代物，结直肠癌（CRC）靶向治疗药物的开发受到阻碍。该初步研究评估了免疫磁性分离分离循环肿瘤细胞（CTC）的能力以及荧光显微镜系统和流式细胞术计数和表征转移性CRC患者CTC的能力。患者和方法：50例转移性CRC患者在治疗开始和疾病评估时间点捐献了50 mL血液。从17例患者中获得新鲜肿瘤标本，以比较循环和原位肿瘤细胞特征。从全血中磁性分离上皮细胞，靶向抗上皮细胞粘附分子（EpCAM）。循环肿瘤细胞定义为EpCAM分离的、细胞角蛋白阳性、核染色阳性和CD 45阴性。从EpCAM富集的CTC中分离总RNA，并进行多基因逆转录酶聚合酶链反应分析。结果：流式细胞术检测到的CTC的中位数为2/7.5mL血液。肿瘤进展与非进展患者的细胞计数平均变化存在显著差异（+6.7 vs. +0.2/7.5 mL; P = 0.001）。CTC和配对肿瘤标本中细胞角蛋白的平均荧光强度（流式细胞术）之间存在相关性（r = 0.79，P = 0.06）。近80%（19例中的15例）具有>= 2个CTC的样本表达>= 1个上皮标记基因（CK 19、CK 20、癌胚抗原或表皮生长因子受体）。结论：从转移性CRC患者中分离和鉴定CTC是可行的。CTC数量的变化可能反映临床状态，流式细胞术和基因表达数据表明循环和原位肿瘤细胞的相似性。有必要进一步评价CTC在CRC患者中的药效学和临床监测。
Purpose: Development of targeted therapeutic agents in colorectal cancer (CRC) is impeded by the lack of a noninvasive surrogate of drug effect. This pilot study evaluated the ability of immunomagnetic separation to isolate circulating tumor cells (CTCs) and of the fluorescent microscope system and flow cytometry to enumerate and characterize CTCs from patients with metastatic CRC. Patients and Methods: Fifty patients with metastatic CRC contributed 50 mL of blood at treatment initiation and disease evaluation timepoints. Fresh tumor specimens were obtained from 17 patients for comparison of circulating and in situ tumor cell characteristics. Epithelial cells were magnetically isolated from whole blood targeting the antiepithelial cell adhesion molecule (EpCAM). Circulating tumor cells were defined as EpCAM isolated, cytokeratin positive, nuclear stain positive, and CD45 negative. Total RNA was isolated from EpCAM-enriched CTCs and multigene reverse-transcriptase polymerase chain reaction analyses were performed. Results: The median number of CTCs detected by flow cytometry was 2/7.5 mL blood. Mean change in cell count was significantly different for patients with tumor progression versus nonprogression (+6.7 vs. +0.2/7.5 mL; P = 0.001). A correlation was noted between mean fluorescence intensity (flow cytometry) of cytokeratin in CTC and matched tumor specimens (r = 0.79, P = 0.06). Nearly 80% (15 of 19) of samples with >= 2 CTCs expressed >= 1 epithelial marker gene (CK19, CK20, carcinoembryonic antigen, or epidermal growth factor receptor). Conclusion: Isolating and characterizing CTCs from patients with metastatic CRC is feasible. Change in the CTC number might reflect clinical status, and flow cytometric and gene expression data suggest similarity of circulating and in situ tumor cells. Further evaluation of CTCs for pharmacodynamic and clinical monitoring in patients with CRC is warranted.