Quantitative oncogene-mapping within malignant tumors through Multi-parameter MRI based on RNA-triggered nanoprobes

Area of Science:

• Biomedical Engineering
• Molecular Imaging
• Nanotechnology

Background:

• Genomic instability is a hallmark of cancer, necessitating precise oncogene detection for early diagnosis.
• Detecting low-abundance oncogenes in vivo remains a significant challenge for current imaging techniques.

Purpose of the Study:

• To develop a quantitative magnetic resonance imaging (MRI) strategy for analyzing tumor-associated microRNA (miRNA) using magnetic resonance tuning (MRET).
• To establish a method for early tumor diagnosis and pathological analysis through precise oncogene quantification.

Main Methods:

• Integrated superparamagnetic iron oxide (Fe3O4) nanoparticles and paramagnetic gadolinium (Gd-DTPA) enhancers via a DNA linker.
• Embedded AS1411 aptamers for targeting overexpressed nucleolins in tumor cells.
• Utilized hybridization with target miRNA to release Gd3+-labeled sequences, enhancing T1 signals for miRNA quantification.

Main Results:

• Verified the MRET effect in vitro with varying concentrations of miR-21.
• Visualized enhanced T2 and activated T1 signals in vivo in 4T1 and CT26 subcutaneous tumor models.
• Established a quantitative correlation between MRI signals and local miR-21 concentration in vivo.

Conclusions:

• The developed nanoprobes show potential for precise tumor-related gene diagnosis and quantification.
• This approach offers a promising avenue for prompt and accurate tumor diagnosis through miRNA analysis.