Figure 1.

The overview of CTCs’ biology, isolation techniques, and clinical application of CTC. (A) CTCs detach from the primary tumor, enter the blood, and then undergo the stages of intravasation, circulation, and extravasation to reach the occurrence of distant metastasis of the tumor. (B) CTCs in the blood can be isolated through immunological and biophysical principles. Immunological methods include positive and negative screening, while biophysical methods include based-on-size, density, and dielectrophoresis. (C) The isolated CTCs can be used clinically as a biomarker and an effective tool for diagnosis, prognosis, and treatment monitoring. Created with Biorender. Abbreviations: DEP, dielectrophoresis.