Isolating Circulating Cancer Stem Cells (CCSCs) from Human Whole Blood

Measuring circulating tumor cells (CTCs) or circulating cancer stem cells (CCSCs) in blood, which shed from primary tumors, is a noninvasive method to screen and/or diagnose patients with a high risk of developing metastatic cancers or relapse. Here, we describe an optimized and standardized laboratory method for isolating CCSCs from human blood samples, using cancer-specific stem cell biomarkers (Kantara et al., Lab Invest 95:100–112, 2015). When performing this technique, 0–1 circulating epithelial tumor cells/mL blood should be expected in patients free of malignant adenocarcinomas compared to over 3 circulating cancer stem cells/mL blood in patients positive for malignant adenocarcinomas (Kantara et al., Lab Invest 95:100–112, 2015).