Liquid Biopsy of Hepatocellular Carcinoma: Circulating Tumor-Derived Biomarkers

Figure 2

Schematic model of CTCs enrichment and further identification of molecular information. Enrichment of CTCs from the peripheral blood of cancer patients is based on the following principles: CTCs can be enriched on the basis of physical properties, including size (filtration-based devices), density (Ficoll centrifugation), and electric charges (dielectrophoresis) (a). CTCs can also be positively or negatively enriched on the basis of the expression of cell surface markers (EpCAM for positive selection and CD45 for negative selection) (b). CTCs can also be trapped from PBMCs by flowing through posts in a microfluidic chip on the basis of both physical and biological properties (c). The subsequent analysis of CTCs including fluorescence in situ hybridization (FISH), microarray, immunofluorescence, sequencing, flow cytometry, and RT-PCR (d).