Enhanced capture system for mesenchymal‑type circulating tumor cells using a polymeric microfluidic device 'CTC‑Chip'...

Area of Science:

• Biomedical Engineering
• Oncology
• Cancer Diagnostics

Background:

• Current clinical methods for capturing circulating tumor cells (CTCs) rely on epithelial cell adhesion molecule (EpCAM) and fail to detect cells undergoing epithelial-mesenchymal transition (EMT).
• EMT-CTCs are crucial for metastasis, highlighting a significant limitation in existing diagnostic technologies.

Purpose of the Study:

• To develop and evaluate a novel EpCAM-independent microfluidic device for capturing CTCs.
• To enable the detection of cancer-specific EMT markers, specifically cell surface vimentin (CSV), for improved CTC identification.

Main Methods:

• A versatile polymeric microfluidic 'CTC-chip' was engineered for antibody conjugation.
• Chips were functionalized with anti-EpCAM and anti-CSV antibodies.
• Capture efficiency was assessed using lung and colon cancer cell lines with varying EMT characteristics spiked into blood and PBS.

Main Results:

• The EpCAM-chip effectively captured epithelial and intermediate cells but showed low efficiency for mesenchymal cells (A549).
• The CSV-chip demonstrated significant capture of mesenchymal-type cells (A549), with improved efficiency at higher antibody concentrations.
• CSV-chip performance in blood samples showed promising, albeit lower, capture rates for mesenchymal cells compared to PBS.

Conclusions:

• The developed CSV-chip offers a promising solution for capturing EpCAM-negative, mesenchymal-type CTCs.
• This technology has potential for improved detection of EMT-CTCs, crucial for understanding and targeting metastasis.