Characterizing for Subcellular Physical Property Changes of Chemotherapy Drug-Resistant Malignant Cancer Cells

Area of Science:

• Biophysics
• Cell Biology
• Nanotechnology

Background:

• Scanning ion conductance microscopy (SICM) is a noncontact nanoprobe tool for analyzing soft biological samples, particularly living cells.
• Cell surface physical properties, like stiffness, can serve as label-free biomarkers for distinguishing tumor from normal cells, fueling interest in cancer research.
• The role of physical factors, such as matrix stiffness and stress, in contributing to tumor drug resistance is increasingly recognized, yet quantification in drug-resistant cells for targeted therapy is underexplored.

Purpose of the Study:

• To investigate the subcellular physical properties (height, roughness, stiffness) of drug-resistant colorectal cancer cell lines.
• To explore the potential of SICM in understanding and potentially overcoming chemotherapy drug resistance.
• To correlate physical property changes in drug-resistant cells with implications for targeted cancer therapy.

Main Methods:

• Established three drug-resistant human colorectal cancer cell lines (DLD1, SW620, HT29) using 5-fluorouracil (5-FU) and oxaliplatin (OXA).
• Employed high-speed SICM to visualize and quantify surface physical properties of both control and drug-resistant cell lines.
• Conducted statistical analysis to compare physical property variations between control and drug-resistant samples.

Main Results:

• Identified distinct changes in subcellular physical properties, including stiffness, in drug-resistant cell lines compared to control samples.
• Observed a reduced change in stiffness in cells simultaneously resistant to 5-FU and OXA.
• Demonstrated SICM's capability to visualize and quantify physical differences at the subcellular level in cancer cells.

Conclusions:

• Subcellular physical properties of drug-resistant cancer cell lines differ from their sensitive counterparts.
• SICM is a valuable tool for characterizing physical attributes of drug-resistant cells, offering insights into targeted therapy strategies.
• This research highlights SICM's potential to aid in developing targeted therapies for overcoming chemotherapy drug resistance in cancer treatment.