Lenalidomide derivatives and proteolysis-targeting chimeras for controlling neosubstrate degradation

Area of Science:

• Chemical Biology
• Oncology
• Molecular Biology

Background:

• Lenalidomide, an immunomodulatory drug (IMiD), is a cornerstone therapy for hematological cancers like multiple myeloma (MM) and 5q myelodysplastic syndromes (5q MDS).
• IMiDs function as molecular glues, hijacking CRL4CRBN to degrade specific neosubstrates, a process central to their therapeutic action.
• Current IMiDs and IMiD-based Proteolysis-Targeting Chimeras (PROTACs) lack neosubstrate selectivity, degrading proteins involved in embryonic development and disease progression.

Purpose of the Study:

• To investigate the role of lenalidomide's 6-position modifications in controlling neosubstrate selectivity for targeted protein degradation (TPD).
• To evaluate the anti-proliferative effects of novel 6-position-modified lenalidomide derivatives and their corresponding PROTACs in hematological cancer models.

Main Methods:

• Synthesis and characterization of 6-position-modified lenalidomide derivatives.
• Assessment of neosubstrate degradation profiles using biochemical assays.
• Evaluation of anti-proliferative activity in MM and 5q MDS cell lines.
• Development and testing of IMiD-based PROTACs targeting BET proteins.

Main Results:

• 6-fluoro lenalidomide demonstrated selective degradation of IKZF1, IKZF3, and CK1α, key targets in anti-hematological cancer activity.
• The modified lenalidomide derivative exhibited superior anti-proliferative effects on MM and 5q MDS cell lines compared to lenalidomide.
• PROTACs incorporating these derivatives selectively degraded BET proteins with consistent neosubstrate selectivity and potent anti-proliferative activity.

Conclusions:

• Modifications at the 6-position of lenalidomide are critical for achieving selective neosubstrate degradation.
• 6-position-modified lenalidomide derivatives represent a promising strategy for developing more selective and effective TPD agents.
• These findings pave the way for next-generation IMiD-based therapies with improved efficacy and reduced off-target effects in hematological malignancies.