Tumor-Targeted Magnetic Micelles for Magnetic Resonance Imaging, Drug Delivery, and Overcoming Multidrug Resistance.

Nasopharyngeal carcinoma (NPC) is prevalent in Southern China. Unfortunately, current treatments encounter multidrug resistance (MDR). Overexpression of P-glycoprotein (P-gp), resulting in the efflux of chemotherapy drugs, is one of the significant mechanisms causing MDR. d-α-Tocopheryl poly(ethylene glycol) 1000 succinate (TPGS) has been demonstrated to effectively inhibit P-gp expression. The objectives of this study are to improve tumor MRI imaging, optimize docetaxel (DOC) administration, and target P-gp to overcome NPC resistance. Multifunctional micelles of TPGS (MM@DOC), loaded with magnetic nanoparticles, were synthesized for the targeted delivery of the first-line anticancer drug. MM@DOC exhibited greater toxicity and induced higher levels of apoptosis in DOC-resistant NPC cells (C666-1/DOC) compared to DOC. MM@DOC loaded with magnetic nanoparticles improved the quality of tumor MRI imaging. MM@DOC also demonstrated significant antitumor effects in nude mice with C666-1/DOC NPC. In conclusion, MM@DOC exhibited promising inhibitory effects on resistant tumors both in vitro and in vivo, optimized tumor MRI imaging, and showed great potential in drug delivery and overcoming resistance.