Circulating microRNA electrochemical assays in thyroid cancer

Area of Science:

• Biomedical Engineering
• Molecular Diagnostics
• Endocrinology

Background:

• Thyroid cancer diagnosis and surveillance face challenges in distinguishing benign from malignant nodules and monitoring treatment effectiveness.
• Conventional microRNA (miRNA) detection methods like qPCR and sequencing present cost, labor, and standardization hurdles.
• Circulating miRNAs are minimally invasive biomarkers for thyroid cancer, but their clinical utility is hindered by detection technology limitations.

Purpose of the Study:

• To review advancements in electrochemical biosensing for thyroid-relevant circulating miRNAs.
• To identify key preanalytical and analytical factors influencing biosensor performance.
• To discuss the translation of these biosensors from laboratory findings to clinical application.

Main Methods:

• Review of electrochemical biosensing techniques including voltammetry, impedimetry, electrochemiluminescence, and photoelectrochemistry.
• Discussion of nanostructured interfaces (e.g., gold nanoparticles, graphene, MXenes) and amplification strategies (e.g., DSN, HCR, CHA, CRISPR).
• Analysis of preanalytical variables (sample matrix, hemolysis, storage, extraction) and analytical parameters (limit of detection, linear range, functional sensitivity).

Main Results:

• Electrochemical biosensors demonstrate ultra-low analytical limits of detection for thyroid miRNAs.
• Performance is significantly impacted by preanalytical sample handling and matrix effects in patient samples.
• Specific miRNAs (e.g., miR-146b, miR-221, miR-222, miR-21) show potential for diagnosis, risk stratification, and follow-up.
• Multiplexed and cartridge-based platforms show resilience to biological variability.

Conclusions:

• Electrochemical biosensing holds significant potential for non-invasive thyroid cancer diagnostics and surveillance.
• Standardization of preanalytical procedures and robust clinical validation are crucial for widespread adoption.
• Future efforts should focus on inter-study standardization, multi-center validation, and regulatory pathways to accelerate clinical translation.