Multifunctional Nanoplatforms for Endoplasmic Reticulum-Targeted Cancer Therapy.

Innovations in therapeutic modalities and targeted drug delivery are two key approaches to improving the effectiveness of cancer treatment. With the development of therapeutic concepts and nanotechnology, recent research has shifted from tissue- or cell-level drug delivery to organelle-specific delivery to amplify therapeutic effects. Among these organelles, the endoplasmic reticulum (ER) has emerged as a particularly promising target because of its extensive membrane network, which serves as a major site for protein synthesis, lipid metabolism, calcium homeostasis, and intracellular signaling. The disruption of ER function can trigger severe cellular stress and apoptosis, providing a rationale for ER-targeted cancer therapy. However, traditional small-molecule drugs often exhibit poor ER specificity, rapid degradation, and limited intracellular accumulation, significantly restricting their therapeutic potential. In contrast, ER-targeting multifunctional nanoplatforms have demonstrated superior advantages, including enhanced stability, precise localization, controlled drug release, and multimodal therapeutic capabilities. In this Review, we systematically summarize the recent advances in ER-targeting nanotherapeutics and their applications in chemotherapy, phototherapy, immunotherapy, biotherapy, and combination therapy. Furthermore, we discuss the advantages, challenges, and mechanistic insights of these strategies, aiming to provide perspectives on accelerating the clinical translation of ER-targeting precision drugs.