Targeting oncogenic KRAS with molecular brush-conjugated antisense oligonucleotides

Area of Science:

• Biotechnology
• Oncology
• Nanomedicine

Background:

• Mutant KRAS is a critical driver in many human cancers, presenting a significant therapeutic challenge.
• Current treatments for KRAS-driven cancers have limitations, highlighting an unmet clinical need.

Purpose of the Study:

• To develop and evaluate a novel class of bottlebrush polyethylene glycol (PEG)-conjugated antisense oligonucleotides (ASOs) for KRAS depletion.
• To assess the in vivo efficacy and safety of these nanoconstructs in preclinical cancer models.

Main Methods:

• Synthesized bottlebrush PEG-ASO conjugates with a unique branched architecture.
• Administered conjugates systemically to mice bearing human non-small-cell lung carcinoma xenografts.
• Evaluated KRAS levels, tumor growth, pharmacokinetic properties, and potential side effects.

Main Results:

• Bottlebrush PEG-ASO conjugates achieved potent in vivo KRAS depletion and significantly reduced tumor growth.
• The nanoconstructs demonstrated enhanced plasma pharmacokinetics and tumor uptake compared to conventional ASO strategies.
• Unmodified ASOs conjugated to bottlebrush polymers showed efficacy comparable to chemically modified ASOs.
• The conjugates were well-tolerated in mice, with minimal observed side effects.

Conclusions:

• Bottlebrush PEG-ASO conjugates represent a promising therapeutic platform for KRAS-driven cancers.
• This approach enhances ASO properties and allows the use of simpler ASO chemistries.
• Further preclinical and clinical development is warranted for this innovative cancer therapy.