Three-Dimensional Telomeric Analysis of Isolated Circulating Tumor Cells (CTCs) Defines CTC Subpopulations

Abstract

Circulating tumor cells (CTCs) have been identified with the potential to serve as suitable biomarkers for tumor stage and progression, but the availability of effective isolation technique(s) coupled with detailed molecular characterization have been the challenges encountered in making CTCs clinically relevant. For the first time, we combined isolation of CTCs using the ScreenCell filtration technique with quantitative analysis of CTC telomeres by TeloView. This resulted in the identification and molecular characterization of different subpopulations of CTCs in the same patient. Three-dimensional (3D) telomeric analysis was carried out on isolated CTCs of 19 patients that consisted of four different tumor types, namely, prostate, colon, breast, melanoma, and one lung cancer cell line. With telomeric analysis of the filter-isolated CTCs, the level of chromosomal instability (CIN) of the CTCs can be determined. Our study shows that subpopulations of CTCs can be identified on the basis of their 3D telomeric properties.

Pathways and therapeutic targets in melanoma

“…The methodology was successfully tested in epithelial cancer and melanoma, and enables RNA profiling of single cells. Isolation of CTC using the ScreenCell filtration technique with quantitative analysis of CTC telomeres by TeloView was described recently [341]. …”

Challenges in circulating tumor cell detection by the CellSearch system

“…The earlier versions of the image analysis software had the tools incorporated to enumerate tumor cell clusters, but to simplify matters it was omitted from the commercial versions of the software. These tumor cell clusters are also observed using other platforms (Aceto et al., 2014; Adebayo Awe et al., 2013; Hosokawa et al., 2013; Molnar et al., 2001; Sarioglu et al., 2015; Werner et al., 2015) but also for these platforms no clear guidance is provided what is and what is not a cluster. A minority of these clusters are composed of tumor cells and lymphocytes of which an example is shown in the figure.…”

Liquid biopsy - emergence of a new era in personalized cancer care

“…As CTCs differ in size from other blood components, size-based filtration systems have been frequently used by numerous authors to enrich them [108]. Generally, the filtration system consists of a filtration tube containing the membrane, a manifold vacuum plate with valve settings, a vacuum manifold and a vacuum pump [109][110][111]. Following filtration, CTCs can be stained by standard immuhistochemistry techniques to identify specific proteins or nucleic acid can be extracted and analyzed by ddPCR or NGS to identify mutations [107,[112][113][114].…”