Dendronized Polymeric Biomaterial for Loading, Stabilization, and Targeted Cytosolic Delivery of microRNA in Cancer...

Area of Science:

• Biomaterials Science
• Nanotechnology
• Molecular Biology
• RNA Therapeutics

Background:

• MicroRNAs (miRNAs) are crucial regulators of gene expression.
• Anti-miRNA agents, a type of RNA-interference (RNAi) therapy, show promise but face delivery challenges.
• Current USFDA-approved RNAi therapeutics (ONPATTRO, Leqvio) highlight the need for effective delivery systems.

Purpose of the Study:

• To develop a novel nanobiomaterial for the selective delivery of anti-miRNA into cancer cells.
• To create a cationic dendronized hyaluronic acid polymer (dCHA) using a USFDA-approved biopolymer.
• To evaluate the dCHA's potential as a carrier for anti-miRNA therapeutics, overcoming delivery hurdles.

Main Methods:

• Synthesis of cationic dendronized HA polymer (dCHA) via focal cationization using a ligated dendron motif.
• Hemolysis assay to assess dCHA's hemocompatibility.
• Molecular simulation and docking (GROMACS) to evaluate binding affinity to CD44 and interaction with macrophages/albumin.
• Assessment of anti-miR21 loading capacity, RNase protection, and lysoendosomal escape via proton sponge effect.
• Evaluation of CD44-receptor-mediated cellular uptake using FAM-labeled anti-miR21 and assessment of gene expression changes (Bax, CASP3, Bcl2).

Main Results:

• Synthesized dCHA demonstrated hemocompatibility and strong binding affinity for the CD44 receptor.
• dCHA exhibited high anti-miR21 loading efficiency, protected it from RNase degradation, and facilitated cytosolic delivery.
• dCHA-mediated delivery of anti-miR21 led to significant downregulation of miR21 and modulation of target gene expression (Bax, CASP3, Bcl2).

Conclusions:

• The developed dCHA is a suitable nanobiomaterial for loading, preserving, and selectively delivering anti-miRNA therapeutics to cancer cells.
• The CD44-receptor-mediated uptake mechanism was confirmed, highlighting targeted delivery potential.
• This approach offers a versatile platform for various gene therapeutics beyond anti-miR21.