Liposomes in Breast Cancer Therapy: Applications and Recent Research Progress

Breast cancer presents marked molecular and phenotypic heterogeneity, often requires prolonged treatment, and remains prone to drug resistance and recurrence. Conventional chemotherapy is still constrained by systemic toxicity and injury to non-target tissues. With a phospholipid bilayer surrounding an aqueous core, liposomes can carry both hydrophobic and hydrophilic drugs. Control of particle size, membrane composition, surface charge, and ligand density can improve drug stability, pharmacokinetics, and tissue distribution. This review outlines liposome structure and preparation, then considers three functional groups used in breast cancer therapy: conventional liposomes, PEGylated long-circulating liposomes, and specialized systems such as thermosensitive, pH-sensitive, and ligand-targeted liposomes. Responsiveness to heat or acidity may release a payload within a tumor, whereas ligand modification can increase receptor-mediated cellular uptake. In practice, protein corona formation, receptor heterogeneity, PEG shielding, and the local tumor microenvironment can weaken these intended effects. Translation to the clinic is further limited by patient-to-patient variation in the enhanced permeability and retention (EPR) effect, storage and in vivo stability, photosensitizer-related phototoxicity, batch-to-batch consistency, and the demands of large-scale manufacturing. Future work should match tumor microenvironmental features with external stimuli, including temperature and light, to build delivery platforms with more predictable and stratified performance. Companion diagnostics, critical quality attribute control, and standardized clinical evaluation will also be needed to establish the safety, efficacy, and translational value of liposome-based therapy.