Mochizuki Chihiro, Nakamura Junna, Nakamura Michihiro
Department of Organ Anatomy & Nanomedicine, Graduate School of Medicine, Yamaguchi University, 1-1-1 minami-Kogushi, Ube, Yamaguchi 755-8505, Japan.
Core Clusters for Research Initiatives of Yamaguchi University, 1-1-1 minami-Kogushi, Ube, Yamaguchi 755-8505, Japan.
ACS Omega. 2023 Mar 3;8(10):9569-9582. doi: 10.1021/acsomega.3c00096. eCollection 2023 Mar 14.
In radiotherapy, the use of Au nanoparticles (Au NPs) has been proposed to enhance cell damage by X-ray irradiation. Although the role of Au in radiotherapy is not fully understood, the catalytic activity of Au has been actively studied in the industrial field. Moreover, owing to their enzyme-like activity and high biocompatibility and , Au NPs present significant potential for biological applications. In this study, we incorporated different Au states both on the surface and embedded in thiol-organosilica (thiol-OS/Au series) to investigate the efficiency of anticancer cell activity of Au in radiotherapy. The thiol-OS/Au series comprised different Au(I)/Au(0) ratios and Au NPs, and different sizes of Au NPs were embedded in thiol-OS/Au. These thiol-OS/Au series samples were evaluated for enzyme-like activities in reactive oxygen species (ROS) generation by X-ray irradiation. Thiol-OS/Au embedded with small Au NPs (AC600/thiol-OS/Au) exhibited peroxidase (POD)-like activity under acidic conditions. This POD-like activity improved ROS generation and cytotoxicity under X-ray irradiation. Furthermore, AC600/thiol-OS/Au exhibited catalase (CAT)-like activity under basic conditions and showed no cytotoxicity toward nonirradiated cells. These results revealed the efficiency of functionalizing with small Au NPs that possess pH-controlled POD- and CAT-like activity as a radiosensitizer. We compared the suitability of using Au with different states to obtain the thiol-OS/Au series samples for application as radiosensitizers. The findings of this study will aid the design of efficacious strategies for the Au nanostructure-based radiotherapy of cancer cells.
在放射治疗中，有人提出使用金纳米颗粒（Au NPs）来增强X射线照射对细胞的损伤。尽管金在放射治疗中的作用尚未完全明确，但金的催化活性在工业领域已得到积极研究。此外，由于其类似酶的活性以及高生物相容性，金纳米颗粒在生物应用方面具有巨大潜力。在本研究中，我们将不同状态的金同时整合到硫醇 - 有机硅的表面和内部（硫醇 - OS/Au系列），以研究金在放射治疗中对癌细胞的抗癌活性效率。硫醇 - OS/Au系列包含不同的Au(I)/Au(0)比例和金纳米颗粒，并且不同尺寸的金纳米颗粒被嵌入到硫醇 - OS/Au中。通过X射线照射，对这些硫醇 - OS/Au系列样品在活性氧（ROS）生成方面的类似酶活性进行了评估。嵌入小金纳米颗粒的硫醇 - OS/Au（AC600/硫醇 - OS/Au）在酸性条件下表现出类似过氧化物酶（POD）的活性。这种类似POD的活性在X射线照射下提高了ROS的生成和细胞毒性。此外，AC600/硫醇 - OS/Au在碱性条件下表现出类似过氧化氢酶（CAT）的活性，并且对未照射的细胞没有细胞毒性。这些结果揭示了用具有pH控制的类似POD和CAT活性的小金纳米颗粒作为放射增敏剂进行功能化的效率。我们比较了使用不同状态的金来获得硫醇 - OS/Au系列样品作为放射增敏剂的适用性。本研究的结果将有助于设计基于金纳米结构的癌细胞放射治疗有效策略。
