Exosomes are a type of tiny vesicles released by cells, which contain bioactive molecules such as proteins, nucleic acids, and lipids secreted by cells. Exosomes released by different cells play an important role in tumor development and metastasis. These exosomes can regulate the tumor microenvironment, promote the tumor growth and invasion, and participate in the process of distant metastasis by carrying specific proteins and nucleic acids. In addition, some biomarkers in exosomes can serve as potential biomarkers for early diagnosis and prognosis evaluation of osteosarcoma. This article reviews the research progress of exosomes in osteosarcoma, aiming to gain a deeper understanding of their mechanisms of action in this disease and provide a reference for the development of new treatment strategies and prognostic evaluation indicators.
Objective To review the research progress on bone repair biomaterials with the function of recruiting endogenous mesenchymal stem cells (MSCs). Methods An extensive review of the relevant literature on bone repair biomaterials, particularly those designed to recruit endogenous MSCs , was conducted, encompassing both domestic and international studies from recent years. The construction methods and optimization strategies for these biomaterials were summarized. Additionally, future research directions and focal points concerning this material were proposed. Results With the advancement of tissue engineering technology, bone repair biomaterials have increasingly emerged as an ideal solution for addressing bone defects. MSCs serve as the most critical "seed cells" in bone tissue engineering. Historically, both MSCs and their derived exosomes have been utilized in bone repair biomaterials; however, challenges such as limited sources of MSCs and exosomes, low survival rates, and various other issues have persisted. To address these challenges, researchers are combining growth factors, bioactive peptides, specific aptamers, and other substances with biomaterials to develop constructs that facilitate stem cell recruitment. By optimizing mechanical properties, promoting vascular regeneration, and regulating the microenvironment, it is possible to create effective bone repair biomaterials that enhance stem cell recruitment. Conclusion In comparison to cytokines, phages, and metal ions, bioactive peptides and aptamers obtained through screening exhibit more specific and targeted recruitment functions. Future development directions for bone repair biomaterials will involve the modification of peptides and aptamers with targeted recruitment capabilities in biological materials, as well as the optimization of the mechanical properties of these materials to enhance vascular regeneration and adjust the microenvironment.