Two-stage microfluidic chip for selective isolation of circulating tumor cells (CTCs)

Area of Science:

• Biomedical Engineering
• Cancer Research
• Microfluidics

Background:

• Circulating tumor cells (CTCs) are crucial for cancer research but are rare and heterogeneous.
• Existing CTC isolation methods (positive and negative enrichment) have limitations like bias or low purity.
• Overcoming these limitations is key to advancing cancer diagnostics and treatment.

Purpose of the Study:

• To develop a novel two-stage microfluidic chip for efficient CTC isolation and characterization.
• To address the challenges of CTC rarity and heterogeneity in cancer research.
• To enable better understanding of CTCs for personalized cancer therapy.

Main Methods:

• A two-stage microfluidic system combining microfluidic magnetic activated cell sorting (μ-MACS) and geometrically activated surface interaction (GASI) chips.
• The μ-MACS stage removes white blood cells (WBCs).
• The GASI stage selectively isolates CTCs based on surface protein expression (EpCAM, HER2).

Main Results:

• Achieved up to 763-fold enrichment of cancer cells from 5 mL blood samples using the μ-MACS chip.
• Demonstrated successful CTC separation with efficiencies of 10.19%–22.91% using the GASI chip.
• The system effectively isolated CTCs and classified heterogeneous CTCs based on their characteristics.

Conclusions:

• The developed two-stage microfluidic chip offers a promising solution for CTC isolation and heterogeneity analysis.
• This technology can advance research into CTC heterogeneity, crucial for personalized cancer treatment.
• The chip provides a valuable tool for improving cancer diagnostics and therapeutic strategies.