(ChemotherapyAdvisor) – Profiling circulating tumor cells (CTCs) on a cell-by-cell basis is possible and may facilitate the application of liquid biopsies to better model drug discovery, according to a multinational team of researchers. The conclusion is based on a paper entitled “Single Cell Profiling of Circulating Tumor Cells: Transcriptional Heterogeneity and Diversity from Breast Cancer Cell Lines,” which was published online in PLoS One on May 7.
The investigators had several aims for this study. First, they wanted to uncover CTC phenotypes, which offer a potential avenue to inform treatment. Second, they wanted to prove the feasibility of CTC transcriptional profiling by overcoming the limitation of leukocyte contamination. Third, they wanted to allow comparisons to breast cancer cell lines widely used for drug discovery.
The investigators used a MagSweeper, an immunomagnetic enrichment device that isolates live tumor cells from unfractionated blood, to isolate CTCs from breast tumors. “Microfluidic-based single cell transcriptional profiling of 87 cancer-associated and reference genes showed heterogeneity among individual CTCs, separating them into two major subgroups, based on 31 highly expressed genes. CTC profiles were distinct from those of cancer cell lines, questioning the suitability of such lines for drug discovery efforts for late-stage cancer therapy.”
The investigators concluded that “for the first time, one can directly measure high dimensional gene expression in individual CTCs without the common practice of pooling such cells. These findings demonstrate that profiling CTCs on a cell-by-cell basis is possible and may facilitate the application of liquid biopsies to better model drug discovery.”