Department of Cancer Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia Pennsylvania.
Institute of Biochemistry and Clinical Biochemistry, Laboratory of Clinical Molecular and Personalized Diagnostics, Catholic University of the Sacred Heart, Rome, Italy.
Clin Cancer Res. 2017 Oct 15;23(20):6086-6093. doi: 10.1158/1078-0432.CCR-17-1173. Epub 2017 Jul 5.
Early detection is essential for treatment plans before onset of metastatic disease. Our purpose was to demonstrate feasibility to detect and monitor estrogen receptor 1 () gene mutations at the single circulating tumor cell (CTC) level in metastatic breast cancer (MBC). We used a CTC molecular characterization approach to investigate heterogeneity of 14 hotspot mutations in and their correlation with endocrine resistance. Combining the CellSearch and DEPArray technologies allowed recovery of 71 single CTCs and 12 WBC from 3 ER-positive MBC patients. Forty CTCs and 12 WBC were subjected to whole genome amplification by MALBAC and Sanger sequencing. Among 3 selected patients, 2 had an mutation (Y537). One showed two different variants in a single CTC and another showed loss of heterozygosity. All mutations were detected in matched cell-free DNA (cfDNA). Furthermore, one had 2 serial blood samples analyzed and showed changes in both cfDNA and CTCs with emergence of mutations in (Y537S and T570I), which has not been reported previously. CTCs are easily accessible biomarkers to monitor and better personalize management of patients with previously demonstrated ER-MBC who are progressing on endocrine therapy. We showed that single CTC analysis can yield important information on clonal heterogeneity and can be a source of discovery of novel and potential driver mutations. Finally, we also validate a workflow for liquid biopsy that will facilitate early detection of mutations, the emergence of endocrine resistance and the choice of further target therapy. .
早期检测对于转移性疾病发作前的治疗计划至关重要。我们的目的是证明在转移性乳腺癌（MBC）中检测和监测雌激素受体 1 () 基因突变的单循环肿瘤细胞（CTC）水平的可行性。我们使用 CTC 分子特征分析方法来研究 14 个热点突变在中的异质性及其与内分泌抵抗的相关性。结合 CellSearch 和 DEPArray 技术，从 3 名 ER 阳性 MBC 患者中回收了 71 个单 CTC 和 12 个白细胞。将 40 个 CTC 和 12 个白细胞用 MALBAC 和 Sanger 测序进行全基因组扩增。在 3 名选定的患者中，有 2 名发生了 突变（Y537）。1 名 CTC 中显示出两种不同的 变体，另一名则显示出杂合性丢失。所有突变均在匹配的无细胞 DNA (cfDNA) 中检测到。此外，有 1 名患者进行了 2 次连续的血液样本分析，显示 cfDNA 和 CTCs 均发生变化，出现了 （Y537S 和 T570I）突变，这在以前的报道中尚未见报道。CTC 是一种易于获取的生物标志物，可用于监测和更好地个性化管理先前证实的 ER-MBC 患者，这些患者在内分泌治疗中进展。我们表明，单个 CTC 分析可以提供关于克隆异质性的重要信息，并且可以成为发现新的和潜在的驱动突变的来源。最后，我们还验证了一种液体活检工作流程，该流程将有助于早期检测 突变、内分泌抵抗的出现以及选择进一步的靶向治疗。
