Accessory microRNA byproducts expand RNA interference via microprocessor-mediated cleavage activation.

Area of Science:

• Biotechnology
• Molecular Biology
• Genomics

Background:

• RNA medicine faces challenges in treating complex diseases like cancer due to multiple abnormal pathways.
• Current therapeutic strategies struggle to address multifactorial diseases effectively.

Purpose of the Study:

• To develop a novel microRNA-based platform for simultaneous up- and down-regulation of microRNAs.
• To demonstrate the therapeutic potential of this platform in a glioblastoma model.
• To target difficult-to-drug pathways like nuclear factor κB (NF-κB).

Main Methods:

• Exploited unique microRNA processing features using a microprocessor-dependent, cleave-activation strategy.
• Designed chimeric microRNA clusters to simultaneously modulate multiple microRNAs and enable aptamer chaperoning.
• Tested the platform in a glioblastoma model, targeting five deregulated microRNAs and the NF-κB pathway via an anti-p50 aptamer.

Main Results:

• Achieved simultaneous bidirectional modulation of microRNAs, leading to significant anti-tumor effects in glioblastoma.
• Successfully employed microRNA-mediated chaperoning to deliver an anti-p50 aptamer, blocking the NF-κB pathway.
• Demonstrated the platform's ability to interfere with critical tumor mass and target a previously difficult-to-drug pathway.

Conclusions:

• Chimeric microRNA clusters represent a promising therapeutic concept for multifactorial diseases, including cancer.
• The developed platform offers a novel strategy for simultaneously targeting multiple molecular pathways.
• This approach has the potential to overcome limitations of current RNA medicine in complex diseases.