Today, cancer remains one of the world’s deadliest diseases, with more than 10 million new cases diagnosed each year. The main cancer treatment methods including surgery, chemotherapy and radiotherapy have been widely used in clinical practice, but they all have their own defects. For example, the toxic side effects of chemotherapy and the low absorption efficiency of radiation at the tumor site. Chemo-radiotherapy (radiotherapy) has been widely used in clinical trials in recent years, and a large number of clinical results have shown that it is more effective in killing tumours than radiotherapy alone. Total chemoradiotherapy has these advantages, but the accumulation of common chemotherapeutic drugs to normal cells will lead to a sharp increase in the toxic and side effects of chemoradiotherapy, which to a large extent limits the clinical application of combination therapy.
With the development of nanotechnology, nano-related tumor targeted therapy has attracted people’s attention. In chemotherapy, researchers have designed various types of nanodrug carriers (such as mesoporous silica nanoparticles) to deliver drugs to tumor areas, improving treatment effectiveness and reducing chemotherapy side effects. In radiotherapy, many nanomaterials containing high-Z elements (such as Au,Bi,W,Ta,Hf, etc.) have also been applied to sensitize radiotherapy.
As a new nano carrier, mesoporous nano tantalum oxide particles designed and prepared by Zhuang Liu’s research group at Soochow University not only have good drug carrier performance, but also can produce radiotherapy sensitization effect. Under the condition of reducing toxicity to mice, it can effectively combine radiotherapy and chemotherapy to further improve the therapeutic effect. The mesoporous nano tantalum oxide particles are prepared by soft template method in one step, and then the layer by layer modification method is adopted to modify the surface of the material, such as polyethylene glycol and other biomolecules, so that the nano particles have good biocompatibility and low toxicity. Mesoporous tantalum oxide nanosystems can efficiently load adriamycin, prolong the half-life of drugs in vivo, and achieve ph-responsive drug release at the tumor site, which is conducive to tumor targeted chemotherapy. On the other hand, tantalum itself has a good radiotherapy sensitization effect, which makes the final radiotherapy and chemotherapy treatment effect significantly improved. In addition, the toxic side effects of the system were significantly reduced compared to the deaths of experimental mice caused by chemotherapy and radiation with free doxorubicin.
This study will open a window for nano drug delivery system to be used in combination therapy with radiotherapy and chemotherapy, and it is expected to become an efficient and safe multifunctional nano drug delivery system in the future.