Quantification of Protein Secretion from Circulating Tumor Cells in Microfluidic Chambers

Area of Science:

• Biomedical Engineering
• Oncology
• Microfluidics

Background:

• Circulating tumor cells (CTCs) are crucial for cancer metastasis and monitoring treatment efficacy.
• Current methods for CTC analysis are limited in providing detailed phenotypic and functional information.
• Understanding CTC secretion profiles can offer valuable insights into tumor behavior.

Purpose of the Study:

• To develop and validate a microfluidic platform for integrated capture, isolation, and analysis of CTCs.
• To enable quantification of secreted proteins from single CTCs and CTC clusters.
• To advance the functional profiling of CTCs for improved cancer diagnostics.

Main Methods:

• A microfluidic device with dedicated trapping structures for high-efficiency CTC capture (>95%).
• Integration of functionalized magnetic beads for co-capture and assessment of protein secretion.
• Application of bead-based assays for quantifying secreted proteins, including granulocyte growth stimulating factor (G-CSF).
• Testing with breast cancer cell lines and mouse-model-derived CTCs.

Main Results:

• Demonstrated high-efficiency isolation of CTCs from whole blood.
• Successfully quantified protein secretion from single CTCs and CTC clusters.
• Achieved a limit of detection of 1.5 ng mL⁻¹ for secreted proteins.
• Identified G-CSF secretion, linking it to neutrophil recruitment.

Conclusions:

• The developed microfluidic platform enables comprehensive functional profiling of CTCs.
• This technology enhances the ability to analyze CTC phenotypes and secreted factors.
• The platform holds potential for multiplexed analysis and future clinical applications in cancer management.