Mayer Julie Ann, Pham Tam, Wong Karina L, Scoggin Jayne, Sales Edgar V, Clarin Trisky, Pircher Tony J, Mikolajczyk Stephen D, Cotter Philip D, Bischoff Farideh Z
Biocept Inc., San Diego, CA, USA.
Cancer Genet. 2011 Nov;204(11):589-95. doi: 10.1016/j.cancergen.2011.10.011.
Determination of HER2 status in breast cancer patients is considered standard practice for therapy selection. However, tumor biopsy in patients with recurrent and/or metastatic disease is not always feasible. Thus, circulating tumor cells (CTCs) are an alternative source of tumor cells for analysis of HER2. An antibody cocktail for recovery of variable, high- and low-, EpCAM-expressing tumor cells was developed based on FACS evaluation and then verified by CTC enumeration (based on CK and CD45 staining) with comparison to EpCAM-only and with CellSearch® (n=19). HER2 fluorescence in situ hybridization (FISH) on all (CK+ and CK-) captured cells was compared to HER2 status on the primary tumors (n=54) of patients with late stage metastatic/recurrent breast cancer. Capture of low EpCAM-expressing tumor cells increased from 27% to 76% when using the cocktail versus EpCAM alone, respectively. Overall, CTC detection with the OncoCEE™ platform was better compared to CellSearch® (68% vs. 89%, respectively), and a 93% concordance in HER2 status was observed. HER2 FISH analysis of CK+ and CK- CTCs is feasible using the CEE™ platform. Although larger clinical studies are warranted, the results demonstrate adequate sensitivity and specificity as needed for incorporation into laboratory testing.
确定乳腺癌患者的HER2状态被认为是治疗选择的标准做法。然而，对复发和/或转移性疾病患者进行肿瘤活检并不总是可行的。因此，循环肿瘤细胞（CTC）是分析HER2的肿瘤细胞的另一种来源。基于流式细胞术评估开发了一种用于回收表达可变、高和低EpCAM的肿瘤细胞的抗体鸡尾酒，然后通过CTC计数（基于细胞角蛋白和CD45染色）与仅使用EpCAM以及与CellSearch®（n = 19）进行比较进行验证。将所有（细胞角蛋白阳性和细胞角蛋白阴性）捕获细胞上的HER2荧光原位杂交（FISH）与晚期转移性/复发性乳腺癌患者原发肿瘤（n = 54）上的HER2状态进行比较。与单独使用EpCAM相比，使用该鸡尾酒时低EpCAM表达肿瘤细胞的捕获率分别从27%提高到76%。总体而言，与CellSearch®相比，使用OncoCEE™平台检测CTC的效果更好（分别为68%对89%），并且观察到HER2状态的一致性为93%。使用CEE™平台对细胞角蛋白阳性和细胞角蛋白阴性CTC进行HER2 FISH分析是可行的。尽管需要进行更大规模的临床研究，但结果表明其具有纳入实验室检测所需的足够敏感性和特异性。
