肿瘤细胞对化疗药物产生耐药性是肿瘤治疗失败的主要原因之一，而肿瘤干细胞氧化还原环境的异常是导致肿瘤耐药的重要因素。研究表明，当肿瘤进行化疗时，产生较高的氧化应激反应（ROS）诱导肿瘤细胞凋亡。而由于肿瘤干细胞处于ROS抑制状态，使肿瘤干细胞对化疗药物不敏感，从而产生了耐药。我们设计了一种以四硫键为主要组成骨架的新型介孔硅纳米粒，用于递送化疗药物。四硫键能够与肿瘤干细胞中异常升高的还原性谷胱甘肽（GSH）反应，不仅能够促进介孔硅骨架崩解，使其具有生物可降解性，降低介孔硅纳米粒的毒性；同时，该反应可以降低肿瘤干细胞中GSH的浓度，从而提高肿瘤干细胞的ROS水平，逆转肿瘤干细胞对化疗药物的耐药性，提高肿瘤的治疗效果。本课题提出了以纳米载体自身抑制肿瘤干细胞克服肿瘤耐药的新思路，并协同化学治疗，为肿瘤治疗提供了一种新方案。

Resistance of tumor to chemotherapy is partially one of the main failure to cancer treatment. The main causes of drug resistant is due to the abnormalities of redox environment in cancer stem cells. The current research have showed that tumor cells need higher oxidative stress response to induce the apoptosis when the tumor was treated with chemotherapy drugs. Because of the inhibited state of ROS in cancer stem cells, making cancer stem cells not sensitive to chemotherapy drugs. This is the main mechanism of drug resistance generation . We designed a novel multi-function mesoporous silica nanoparticles to delivery chemotherapy drugs. The cage construction was 4 sulphur keys that could reduce the concentration of GSH in cancer stem cells. This function not only reduced the toxicity of mesoporous silica nanoparticles, but also enhanced ROS and reversed the drug resistant. All together, our study will help explore the feasibility of tumor treatment by multi-function mesoporous silica nanoparticle delivery system and feasibility of treating tumor by eliminating cancer stem cells.