Black-hole system: in vivo continuous bioligand-assisted elimination of circulating tumor cells to prevent cancer recurrence and metastasis

In vivo continuous eradication of circulating tumor cells (CTCs) following chemotherapy represents a promising strategy to prevent cancer recurrence and metastasis, but remains a practical challenge. Here, we propose a bioligand-assisted in vivo therapy for dynamic check and hemo clearance of CTCs, termed the "Black-hole" system. Inspired by hemopurification, the Black-hole system integrates a peristaltic pump to maintain continuous blood flow, a functionalized microfluidic reservoir for CTCs sustained capture, and flexible tubing with needles for in vivo blood withdrawal and reinfusion. In this system, blood is drawn from the left carotid artery, passes through the microfluidic reservoir to selectively withhold CTCs, and is subsequently reinfused into the right jugular vein. Demonstration in a live tumor-bearing mouse model demonstrated the biosafety and efficacy of the system for single-pass, in vivo CTCs elimination. No significant morphological alterations were observed in major organs after the Black-hole system therapy. Notably, mice receiving the Black-hole therapy following paclitaxel chemotherapy exhibited a 50% survival rate, along with a 16.7% reduction in overall tumor recurrence. We expect the Black-hole system to become a safe and effective adjuvant therapy for postoperative cancer management.