%0 Journal Article %T Carboxylated mesoporous silica nanoparticle-nucleic acid chimera conjugate-assisted delivery of siRNA and doxorubicin effectively treat drug-resistant bladder cancer. %A Yang J %A Liu B %A Wang Q %A Yan H %A Li G %A Wang X %A Shang Z %A Ou T %A Chen W %J Biomed Pharmacother %V 178 %N 0 %D 2024 Sep 24 %M 39053429 %F 7.419 %R 10.1016/j.biopha.2024.117185 %X Chemotherapy is the main treatment for bladder cancer, but drug resistance and side effects limit its application and therapeutic effect. Herein, we constructed doxorubicin (DOX)/COOH-mesoporous silica nanoparticle/polyethylenimine (PEI)/nucleic acid chimeras (DOX/MSN/Chimeras) to reduce the toxicity of chemotherapy drugs and the resistance of bladder cancer cells. Transmission electron microscopy showed that PEI was coated on the DOX/MSN/BSA nanoparticles with a diameter of about 150 nm. DOX/MSN/PEI could control DOX release for over 48 h, and the sudden release rate was significantly lower than DOX/MSN. Immunohistochemical results showed that DOX/MSN/Chimera specifically bound to bladder cancer cells, and markedly inhibited PI3K expression and proliferation of DOX-resistant bladder cancer cells. DOX/MSN/Chimera promoted the apoptosis of drug-resistant bladder cancer cells, which was superior to DOX/MSN/Aptamer or DOX/MSN. We further carried out animal experiments and found that DOX/MSN/Chimera could reduce the volume of transplanted tumors in vivo. Compared with DOX/MSN/Aptamer group, the proliferation rate was significantly decreased and the proportion of apoptotic cells was highly increased. Through the histological observation of kidneys and lungs, we believed that DOX/MSN/Chimera can effectively reduce the damage of chemotherapy drugs to normal tissues. In conclusion, we constructed a COOH-MSN/nucleic acid chimera conjugate for the targeted delivery of siRNA and anti-cancer drugs. Our study provides a new method for personalized and targeted treatment of drug-resistant bladder cancer.