Nanostructured manganese dioxide (MnO₂) has attracted extensive attention in the field of anticancer applications. As we all know, the tumor microenvironment is usually characterized by a high glutathione (GSH) concentration, overproduced hydrogen peroxide (H₂O₂), acidity, and hypoxia, which affect the efficacy of many traditional treatments such as chemotherapy, radiotherapy, and surgery. Fortunately, as one kind of redox-active nanomaterial, nanostructured MnO₂ has many excellent properties such as strong oxidation ability, excellent catalytic activity, and good biodegradability. It can be used effectively in diagnosis and treatment when it reacts with some harmful substances in the tumor site. It can not only enhance the therapeutic effect but also adjust the tumor microenvironment. Therefore, it is necessary to present the recent achievements and progression of nanostructured MnO₂ for anticancer applications, including preparation methods, diagnosis, and treatment. Special attention was paid to photodynamic therapy (PDT), bioimaging and cancer diagnosis (BCD), and drug delivery systems (DDS). This review is expected to provide helpful guidance on further research of nanostructured MnO₂ for anticancer applications.

中文翻译：

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纳米结构的二氧化锰，用于抗癌：制备，诊断和治疗。

纳米结构二氧化锰（MnO ₂）在抗癌应用领域引起了广泛的关注。众所周知，肿瘤的微环境通常以高谷胱甘肽（GSH）浓度，过量产生的过氧化氢（H ₂ O ₂），酸性和低氧为特征，这会影响许多传统疗法的疗效，例如化学疗法，放射疗法和手术。幸运的是，作为一种氧化还原活性纳米材料，纳米结构的MnO ₂具有许多优异的性能，例如强氧化能力，出色的催化活性和良好的生物降解性。当它与肿瘤部位的某些有害物质发生反应时，可以有效地用于诊断和治疗。它不仅可以增强治疗效果，而且可以调节肿瘤的微环境。因此，有必要介绍用于抗癌应用的纳米结构MnO ₂的最新成就和进展，包括制备方法，诊断和治疗。特别注意了光动力疗法（PDT），生物成像和癌症诊断（BCD）和药物输送系统（DDS）。该综述有望为进一步研究纳米结构MnO ₂在抗癌中的应用提供有益的指导。