Shaffer David R, Leversha Margaret A, Danila Daniel C, Lin Oscar, Gonzalez-Espinoza Rita, Gu Bin, Anand Aseem, Smith Katherine, Maslak Peter, Doyle Gerald V, Terstappen Leon W M M, Lilja Hans, Heller Glenn, Fleisher Martin, Scher Howard I
Genitourinary Oncology Service, Immunicon Corporation, Huntingdon Valley, Pennsylvania, USA.
Clin Cancer Res. 2007 Apr 1;13(7):2023-9. doi: 10.1158/1078-0432.CCR-06-2701.
To better direct targeted therapies to the patients with tumors that express the target, there is an urgent need for blood-based assays that provide expression information on a consistent basis in real time with minimal patient discomfort. We aimed to use immunomagnetic-capture technology to isolate and analyze circulating tumor cells (CTC) from small volumes of peripheral blood of patients with advanced prostate cancer.
Blood was collected from 63 patients with metastatic prostate cancer. CTCs were isolated by the Cell Search system, which uses antibodies to epithelial cell adhesion marker and immunomagnetic capture. CTCs were defined as nucleated cells positive for cytokeratins and negative for CD45. Captured cells were analyzed by immunofluorescence, Papanicolau staining, and fluorescence in situ hybridization.
Most patients (65%) had 5 or more CTCs per 7.5 mL blood sample. Cell counts were consistent between laboratories (c = 0.99) and did not change significantly over 72 or 96 h of storage before processing (c = 0.99). Their identity as prostate cancer cells was confirmed by conventional cytologic analysis. Molecular profiling, including analysis of epidermal growth factor receptor (EGFR) expression, chromosome ploidy, and androgen receptor (AR) gene amplification, was possible for all prostate cancer patients with >or=5 CTCs.
The analysis of cancer-related alterations at the DNA and protein level from CTCs is feasible in a hospital-based clinical laboratory. The alterations observed in EGFR and AR suggest that the methodology may have a role in clinical decision making.
为了更精准地将靶向治疗应用于表达靶点的肿瘤患者，迫切需要一种基于血液的检测方法，能够在患者不适最小的情况下实时、持续地提供表达信息。我们旨在利用免疫磁捕获技术从晚期前列腺癌患者的少量外周血中分离并分析循环肿瘤细胞（CTC）。
收集63例转移性前列腺癌患者的血液。通过Cell Search系统分离CTC，该系统利用上皮细胞黏附分子抗体和免疫磁捕获技术。CTC被定义为细胞角蛋白阳性、CD45阴性的有核细胞。对捕获的细胞进行免疫荧光、巴氏染色和荧光原位杂交分析。
大多数患者（65%）每7.5 mL血样中有5个或更多的CTC。各实验室之间的细胞计数结果一致（c = 0.99），在处理前储存72或96小时后细胞计数无显著变化（c = 0.99）。通过传统细胞学分析证实了它们作为前列腺癌细胞的身份。对所有每7.5 mL血样中CTC≥5个的前列腺癌患者都可以进行分子分析，包括表皮生长因子受体（EGFR）表达、染色体倍性和雄激素受体（AR）基因扩增分析。
在医院临床实验室中，从CTC进行DNA和蛋白质水平的癌症相关改变分析是可行的。在EGFR和AR中观察到的改变表明该方法可能在临床决策中发挥作用。
