Bone Marrow-Targeted Liposomes Loaded with Bortezomib Overcome Multiple Myeloma Resistance

Area of Science:

• Oncology
• Nanomedicine
• Pharmacology

Background:

• Multiple myeloma (MM) presents significant treatment challenges due to its aggressive nature and development of drug resistance.
• Bortezomib, a proteasome inhibitor, has improved MM therapy but limitations persist.
• Targeted drug delivery systems are needed to enhance efficacy and overcome resistance.

Purpose of the Study:

• To develop and evaluate AMD3100-targeted Bortezomib Liposomes (ATBL) for targeted delivery of bortezomib to multiple myeloma cells.
• To assess the efficacy and safety of ATBL in preclinical models of MM, including bortezomib-resistant clones.
• To investigate the role of CXCR4 in ATBL uptake and therapeutic response.

Main Methods:

• Development of liposomes targeted with AMD3100 for enhanced MM cell uptake via CXCR4.
• In vitro and in vivo evaluation of ATBL efficacy in MM models.
• Assessment of ATBL in bortezomib-resistant MM clones and CXCR4-knockdown models.
• Analysis of ATBL biodistribution and toxicity profiles.

Main Results:

• ATBL demonstrated enhanced uptake in MM cells dependent on CXCR4 expression, both in vitro and in vivo.
• ATBL treatment resulted in superior therapeutic efficacy compared to free bortezomib or non-targeted liposomes in MM-bearing mice.
• Therapeutic activity of ATBL was diminished in CXCR4-knockdown MM cells, indicating CXCR4 as a response biomarker.
• ATBL showed significant efficacy against an aggressive, bortezomib-resistant MM clone.
• Safety and bone marrow-targeting capabilities of ATBL were confirmed.

Conclusions:

• ATBL represents a promising targeted therapy for multiple myeloma, leveraging CXCR4 for enhanced drug delivery.
• This approach demonstrates potential to overcome bortezomib resistance in MM.
• ATBL exhibits favorable safety and biodistribution profiles, suggesting its potential as a next-generation MM therapeutic.