Second-harmonic generation scattering directionality predicts tumor cell motility in collagen gels

Area of Science:

• Biophysics
• Cancer Biology
• Biomaterials

Background:

• Second-harmonic generation (SHG) quantifies collagen structural changes during tumor metastasis.
• SHG directionality (F/B ratio) correlates with collagen fibril diameter, spacing, and packing disorder.
• Distinct F/B ratios are observed in invasive ductal carcinoma (IDC) tumors with varying metastatic potential.

Purpose of the Study:

• To investigate the direct relationship between collagen microstructure and tumor cell motility.
• To explore how varying SHG F/B ratios in collagen gels affect tumor cell migration.

Main Methods:

• Utilized in vitro collagen gels with controlled F/B ratios.
• Assessed tumor cell migration within these engineered collagen environments.
• Measured total distance traveled, average velocity, and maximum velocity of tumor cells.

Main Results:

• A significant correlation was found between the SHG F/B ratio and tumor cell migration parameters.
• Higher F/B ratios were associated with altered total distance, average, and maximum cell velocities.
• Collagen microstructure directly influences tumor cell locomotion in a controlled setting.

Conclusions:

• Tumor cell motility is directly impacted by the structural properties of the surrounding collagen matrix.
• The SHG F/B ratio serves as a potential biomarker for predicting tumor cell invasiveness.
• Collagen's influence on cell motility may be a key mechanism driving metastasis in IDC.