Therapeutic targeting of cancer stem cell-specific surface glycans and glycoproteins

Cancer stem cells (CSCs) represent a critical subpopulation within tumors, driving malignancy, metastasis, and therapeutic resistance. Their unique biological attributes, particularly the distinctive landscape of surface glycans and glycoproteins, offer promising avenues for targeted therapeutic intervention. This comprehensive review explores the pivotal role of CSC-specific surface glycans and glycoproteins, including CD133, CD44 variants, EpCAM, MUC1, gangliosides (GD2, GD3), and truncated O-glycans (Tn, Sialyl Lewis X), as key drivers of CSC properties and therapeutic vulnerabilities. The report details current therapeutic strategies, such as monoclonal antibodies, antibody-drug conjugates, and advanced chimeric antigen receptor (CAR) T, NK, and NKT cell therapies, which are engineered to exploit these surface markers. Furthermore, it examines small molecule inhibitors that target CSC metabolism (metabostemness, the metabolic reprogramming that supports CSC stemness) and induce ferroptosis, a form of regulated cell death characterized by iron-dependent lipid peroxidation, often synergistically. Significant challenges in clinical translation, including achieving specificity, overcoming tumor heterogeneity, modulating the immunosuppressive tumor microenvironment, and addressing manufacturing complexities, are critically discussed. The integration of multi-modal diagnostics, combining multiple diagnostic approaches, encompassing liquid biopsy, advanced imaging, and single-cell epigenomics, is presented as an essential future direction for precision oncology, enabling real-time monitoring and personalized treatment strategies for high-risk cancers like neuroblastoma. This review underscores the imperative for innovative, multi-pronged approaches to effectively eradicate CSCs and achieve durable patient responses.