Hager Gudrun, Cacsire-Castillo Tong Dan, Schiebel Ingrid, Rezniczek Günther A, Watrowski Rafal, Speiser Paul, Zeillinger Robert
Division of Gynaecology, Department of Obstetrics and Gynaecology, Molecular Oncology Group, Medical University of Vienna, Waehringer Guertel 18-20, 5Q A-1090 Vienna, Austria.
Gynecol Oncol. 2005 Aug;98(2):211-6. doi: 10.1016/j.ygyno.2005.04.042.
Metastatic relapse due to early dissemination of tumor cells is associated with poor prognosis for epithelial cancer. The molecular characterization of these single cells or cell clusters that have evaded the tumor is indispensable in order to evaluate their biological behavior and metastatic potential. In this study, we established a sensitive immunomagnetic method to isolate rare cancer cells from peripheral blood based on their expression of epithelial- or tumor-cell-specific markers.
Low numbers of cells of breast cancer cell lines - ZR-75-1, MCF-7, HBL-100 - were spiked into peripheral blood specimens of healthy volunteers. Enrichment of tumor cells was performed using either pre-coupled HEA and/or ErbB2 microbeads or a mixture of three monoclonal antibodies against HEA, ErbB2 and EGFR.
The recovery rate of spiked tumor cells correlated with the expression of the corresponding antigens. ZR-75-1 cells high expressing all three genes could be isolated to 60-71%. MCF-7 cells, which hardly express EGFR, showed a significant better recovery by using two specific antibodies in combination (50-68%) than one pre-coupled bead alone (31-42%). HBL-100 cells little expressing HEA could not be isolated with HEA microbeads and only to 27% in combination with ErbB2 beads -in contrast the use of an antibody cocktail achieved 38%.
As tumor and epithelial specific cell marker antigens are expressed differently in disseminated tumor cells, the immunomagnetic enrichment from peripheral blood is most robust and reliable when using a combination of specific antibodies compared to single antibodies.
肿瘤细胞早期播散导致的转移性复发与上皮癌的不良预后相关。为了评估这些已逃离肿瘤的单个细胞或细胞簇的生物学行为和转移潜能，对其进行分子特征分析必不可少。在本研究中，我们基于上皮或肿瘤细胞特异性标志物的表达，建立了一种从外周血中分离罕见癌细胞的灵敏免疫磁珠法。
将少量乳腺癌细胞系ZR-75-1、MCF-7、HBL-100的细胞加入健康志愿者的外周血标本中。使用预偶联的HEA和/或ErbB2微珠或三种抗HEA、ErbB2和EGFR的单克隆抗体混合物进行肿瘤细胞富集。
加入的肿瘤细胞回收率与相应抗原的表达相关。高表达所有三个基因的ZR-75-1细胞的分离率可达60%-71%。几乎不表达EGFR的MCF-7细胞，联合使用两种特异性抗体时的回收率（50%-68%）明显高于单独使用一种预偶联磁珠（31%-42%）。几乎不表达HEA的HBL-100细胞不能用HEA微珠分离，与ErbB2磁珠联合使用时分离率仅为27%，相比之下，使用抗体混合物时分离率可达38%。
由于肿瘤和上皮特异性细胞标志物抗原在播散肿瘤细胞中的表达不同，与单克隆抗体相比，使用特异性抗体组合从外周血中进行免疫磁珠富集最为有效和可靠。
