Microfluidics-based approaches for separation and analysis of circulating tumor cells

Metastasis is the leading cause of epithelial cancer-associated mortality. The shedding of tumor cells into the circulatory system is a key step for metastasis. Circulating tumor cells (CTCs) are reliable biomarkers for cancer diagnostics and treatment. To obtain clinical information, accurate approaches for separating and analyzing CTCs are necessary. Microfluidic technologies have demonstrated their extraordinary abilities for separating and analyzing CTCs. In this paper, we present a comprehensive review of microfluidics-based approaches for CTCs separation and analysis. We first present the general methods for CTCs separation using the microfluidic chips, including physical properties-based approaches for CTCs enrichment and affinity-based approaches for CTCs capture, and compare the pros and cons of different separation technologies. Then we introduce microfluidics-based CTCs analysis on cellular and molecular levels and the biomedical applications of CTCs analysis. Finally, we summarize the development of microfluidics-based CTCs separation and analysis, and make a prospective of future research.