Amino Acid Polymer-Based Nano-Carriers for Targeted Drug Delivery in Breast Cancer Therapy: Mechanisms, Applications, and Future Perspectives

Breast cancer remains one of the leading causes of mortality among women worldwide, despite remarkable advancements in diagnostic and therapeutic approaches. Conventional treatments such as chemotherapy and radiotherapy continue to face major challenges, including systemic toxicity, adverse side effects, and limited efficacy in advanced stages. Recent developments in nanomedicine have introduced amino acid polymer-based nano-carriers as innovative and promising platforms for targeted drug delivery in breast cancer therapy. These nano-carriers offer superior biocompatibility, controlled and sustained drug release, improved physicochemical stability, and selective targeting of tumor tissues, thereby minimizing off-target toxicity.This review comprehensively discusses the latest progress in amino acid polymer-based nano-carriers, with emphasis on their structural design, drug-loading mechanisms, tumor microenvironment responsiveness, and ligand-mediated targeting strategies. Moreover, it highlights current limitations, translational challenges, and research gaps that need to be addressed to achieve successful clinical implementation. Overall, amino acid polymer-based nano-carriers hold significant potential to revolutionize breast cancer treatment by enhancing therapeutic precision, improving patient outcomes, and contributing to the next generation of personalized nanomedicine.