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© The Author(s) 2021. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http:// creat iveco mmons. org/ licen ses/ by/4. 0/. The Creative Commons Public Domain Dedication waiver (http:// creat iveco mmons. org/ publi cdoma in/ zero/1. 0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data. Background Cancer is an important disease that seriously threatens human health, such as ovarian cancer, which is a salient public health concern and remains the deadliest form of gynaecological malignancy despite of its infrequent incidence [1]. It ranks the 7th most common form of cancer and the 8th leading cause of cancer-related death among women worldwide. [2, 3] Currently, the treatment of cancer includes surgery [4], chemotherapy [4], targeted therapy [5], but it is still difficult to achieve a radical cure of the cancer due to the risk of recurrence and treatment resistance [1, 4]. Therefore, there is an urgent need to find new strategies to treat cancer. With the rapid development of nanomedicine, the application of nanoparticles in anti-tumor therapy has attracted more and more attention. Reactive oxygen species (ROS) are a group of molecules formed from incomplete reduction of oxygen, including superoxide anion (O2), hydrogen peroxide (H2O2), hydroxyl radical (·OH), and so on [6]. Among them, ·OH exhibits indiscriminate reactivity and is highly oxidative to all biological targets [7]. ROS is prevalent in various diseases, for instance cancer, cardiovascular diseases and neurodegenerative diseases [8]. The balance of production and removal of ROS in the niche of normal cells keeps a dynamic balance. Low concentration of ROS in cells mediates intracellular signals, while the over-expression of ROS caused cytotoxicity, leading to apoptosis or necrosis [9]. And high concentration of ROS is recognized as the hallmark of cancer cells, since it is always caused by the alterations in cellular metabolism for supporting their malignant proliferation [10]. Therefore, it is a potential therapy for combating against cancer by the abrogation of redox homeostasis [11, 12]. Due to the excellent reactivity of ·OH, the conversion of H2O2 to ·OH is expected to cause greater oxidative damage in tumor cells. In addition, the standard reduction potential E0′ (H2O2, H/H2O, ·OH) = 320 mV from the electrochemical standpoint [13], which is also thermodynamically viable [14]. Catalysis, as one of the most significant processes occurring in human bodies persistently, helps maintain the general homeostasis [6, 15]. Catalytic chemistry has rapidly developed in recent years, and it provides feasible tools for us to harness redox reactions for biochemical applications by using nanozymes to actuate redox reactions [16]. To deal with malignant cancer with effective therapeutic outcomes and alleviate adverse biotoxicities, pathological and chemical hallmarks in the tumor microenvironment have been applied to provide distinct stimulations to initiate the nanozyme reactions [17–19]. The enzyme-mimetic reagents are able to initiate Fentonlike reactions in tumor cells, and can convert hypotoxic H2O2 into hypertoxic ·OH, resulting in oxidization and inactivation of proteins and organelles in cells abruptly Open Access Journal of Nanobiotechnology