Temperature and Tumor Microenvironment Dual Responsive Mesoporous Magnetic Nanospheres for Magnetothermal Effect-Induced Cancer Theranostics

The development of smart drug delivery systems(SDDSs)based on engineered nanomaterials is important for clinical applications.Nevertheless,controllable administration of chemotherapeutic drugs for deep tumors and the avoidance of side effects caused by off-targeting during delivery remain a great challenge.Herein,a stimulus-responsive system of mesoporous nanospheres(composed of Cu@Fe_(2)C@mSiO_(2))with good magnetothermal effect is introduced into the tumor microenvironment.This system plays an important role in image-guided controllable targeted drug delivery that is independent of tumor depth.Aggregation-induced emission luminogen-based fluorescence imaging and magnetic resonance imaging were utilized since these techniques visualize the delivery process in real time.In addition,the degraded nanocarriers showed high catalytic activity for Fenton and Fenton-like reactions,upregulating the level of hydroxyl radicals(•OH)in cancer cells to realize chemodynamic therapy.The induced•OH led to the overexpression of pho-STAT3,activating the STAT3 signaling pathway,eventually inducing cancer cell apoptosis.Through metabolic monitoring,this SDDS is removed from the body after its degradation in vivo.The synergistically enhanced therapeutic effect was obtained in the chemo-chemodynamic therapy of 4T1 tumor-bearing mice,offering a platform for efficient cancer therapy with a personalized theranostic strategy.

A pH-responsive biomimetic drug delivery nanosystem for targeted chemo-photothermal therapy of tumors

Smart drug delivery nanosystem is significant for tumor treatments due to its possibility of temporally,spatially,and dose-controlled release.However,the therapeutic efficacy of drug delivery nanosystem is often compromised in cancer treatment as the enrichment of therapeutic agents in the reticuloendothelial system.Herein,doxorubicin(DOX)loaded biomimetic drug delivery nanosystem with macrophage cell membrane(MCM)camouflaged,MnFe_(2)O_(4)-DOX-MCM nanocube(NC),is developed for cancer treatment with tumor targeting,pH-stimuli drug release,and chemo-photothermal therapeutic effects.The nanosystem shows the capability of immune escape and enhanced cellular uptake of cancer cells due to the MCM decoration.Acid-labile bond between the MnFe2O4 NCs and DOX remains stable at physiological condition and release drugs immediately in response to the endo-/lysosome pH stimuli.Meanwhile,the photothermal effect of the nanosystem destroys tumor tissue,which further promotes chemotherapeutic efficacy.In vivo results demonstrate the tumor homing ability and produce a notable synergistic therapeutic effect of the NCs.Thus,biomimetic pH-responsive drug delivery nanosystem,MnFe_(2)O_(4)-DOX-MCM NCs,is an effective nanoplatform,which might be potential application for cancer synergistic treatment.