Abstract

Liquid Biopsy using Nanotube-CTC-Chip

Balaji Panchapakesan, Associate Professor, Department of Mechanical Engineering, Worcester Polytechnic Institute (WPI)

We report the further development of the nanotube-CTC-chip for isolation of tumor-derived epithelial cells (circulating tumor cells, CTCs) from peripheral blood, with high purity, by exploiting the physical mechanisms of preferential adherence of CTCs on a nanotube surface. The nanotube-CTC-chip is a new 76-element microarray technology that combines carbon nanotube surfaces with microarray batch manufacturing techniques for the capture and isolation of tumor-derived epithelial cells. Using a combination of red blood cell (RBC) lysis and preferential adherence, we demonstrate the capture and enrichment of CTCs with a 5-log reduction of contaminating WBCs. The nanotube-CTC-chip successfully captured CTCs in the peripheral blood of breast cancer patients (stage 1–4) with a range of 4–238 CTCs per 8.5 ml blood or 0.5–28 CTCs per ml. CTCs (based on CK8/18, Her2, EGFR) were successfully identified in breast cancer patients, and no CTCs were captured in healthy controls. CTC enumeration based on multiple markers using the nanotube-CTC-chip enables dynamic views of metastatic progression and could potentially have predictive capabilities for diagnosis and treatment response.