Nanomedicines targeting myeloid cells for breast cancer therapy

Breast cancer remains the most frequently diagnosed malignancy among women, accounting for over 30 ​% of all cancer cases in this population. Although the incorporation of targeted therapies has significantly improved clinical outcomes, therapeutic resistance and immune evasion continue to undermine durable disease control. Myeloid cells—including monocytes, macrophages, dendritic cells (DCs), and granulocytes—play a pivotal role in orchestrating the tumor microenvironment (TME). While these cells exhibit immunostimulatory properties under physiological conditions, they often adopt immunosuppressive and pro-tumorigenic phenotypes within the TME, thereby facilitating tumor progression, metastasis, and resistance to treatment. Nanomedicine has emerged as a promising platform for modulating the TME, offering enhanced delivery precision, controlled drug release, and the potential to reprogram immune responses. In particular, nanoparticle-based systems—including liposomes, polymeric nanoparticle (PNP), micelles, and hybrid nanomaterials—have been actively investigated for their capacity to selectively target and manipulate myeloid cell populations in breast cancer. By delivering immunomodulatory agents directly to these cells, such strategies aim to reverse their tumor-supportive functions and reinvigorate anti-tumor immunity. This review provides a comprehensive overview of recent advances in nanomedicine-based approaches for targeting myeloid cells in breast cancer. We discuss the underlying biological mechanisms, preclinical efficacy, and translational challenges—including nanoparticle stability, specificity, and scalability—that must be addressed to facilitate clinical implementation. Integrating nanotechnology with immunomodulation represents a promising frontier in precision oncology, with the potential to overcome therapeutic resistance and improve outcomes in breast cancer management. • Myeloid Cells in Breast Cancer -Myeloid cells shift to immunosuppressive roles, driving cancer progression and therapy resistance. • Nanomedicine-Based Targeting -Liposomes, nanoparticles, and micelles modulate myeloid cells, improving breast cancer treatment. • Challenges in Clinical Translation -Stability, targeting, regulatory hurdles, and scalability pose key barriers, needing further research for success.