DNA Clutch Probes for Circulating Tumor DNA Analysis

Area of Science:

• Biochemistry
• Molecular Biology
• Nanotechnology

Background:

• Liquid biopsies offer minimally invasive disease detection.
• Analysis of circulating tumor DNA (ctDNA) is crucial for cancer diagnostics.
• Current ctDNA detection methods lack sensitivity and specificity, struggling to differentiate tumor DNA from normal DNA.

Purpose of the Study:

• To develop a novel electrochemical assay for sensitive and specific detection of mutated ctDNA.
• To overcome the challenge of distinguishing tumor-derived ctDNA from wild-type DNA in blood samples.
• To establish a non-enzymatic amplification method for ctDNA analysis.

Main Methods:

• Utilized DNA clutch probes (DCPs) to selectively expose specific ctDNA sequences.
• DCPs prevent DNA reassociation and deactivate non-target sequences.
• Employed chip-based sensors for electrochemical detection of hybridization events.

Main Results:

• Achieved highly sensitive and specific detection of mutated ctDNA.
• The assay can detect target mutations at 0.01% relative to wild-type DNA (1 fg/μL mutation vs. 100 pg/μL wild-type).
• Successfully analyzed ctDNA in samples from lung cancer and melanoma patients.

Conclusions:

• This study presents the first non-enzymatic electrochemical detection of ctDNA.
• The developed method using DCPs significantly enhances the accuracy of liquid biopsy analysis.
• This approach holds promise for improved early cancer detection and monitoring.