Enhancing Tumor Catalytic Therapy by Co‐Catalysis

Abstract

Fenton reactions have been recently applied in tumor catalytic therapy, whose efficacy suffers from the unsatisfactory reaction kinetics of Fe3+ to Fe2+ conversion. Here we introduce a co‐catalytic concept in tumor catalytic therapy by using a two‐dimensional molybdenum disulfide (MoS2) nanosheet atomically dispersed with Fe species. The single‐atom Fe species act as active sites for triggering Fenton reactions, while the abundant sulfur vacancies generated on the nanosheet favor electron capture by hydrogen peroxide for promoting hydroxyl radical production. Moreover, the 2D MoS2 support also acts as a co‐catalyst to accelerate the conversion of Fe3+ to Fe2+ by the oxidation of active Mo4+ sites to Mo6+, thereby promoting the whole catalytic process. The 2D nanocatalyst exhibits a desirable catalytic performance, as well as a significantly enhanced anticancer efficacy both in vitro and in vivo, which indicates the feasibility for applying such a co‐catalytic concept in tumor therapy.

Novel Strategy for Optimized Nanocatalytic Tumor Therapy: From an Updated View

“…Given that the efficacy of Fenton reactions suffered from the unsatisfactory Fe 3+ to Fe 2+ conversion kinetics, Yang et al [ 30 ] developed a cocatalytic concept in catalytic therapy by introducing a 2D MoS 2 nanosheet atomically dispersed with Fe species. Taking the advantages of SACs and 2D nanosheets, Fenton reactions could be triggered by active sites of the single‐atom Fe species, while the abundant sulfur vacancies generated on the nanosheet facilitated electron capture by H 2 O 2 for elevated •OH production ( Figure 2B ) .…”

“…C) Schematic illustration of antitumor effect of the cocatalyst. Reproduced with permission [30]. Copyright 2022, Wiley-VCH.…”

A core–shell liquid metal-Cu nanoparticle with glutathione consumptionviaanin situreplacement strategy for tumor combination treatment of chemodynamic, microwave dynamic and microwave thermal therapy

“…[1][2][3][4][5] As one of the ROS-based strategies, chemodynamic therapy (CDT) can transform H 2 O 2 into •OH by means of a Fenton or Fenton-like reaction between the nanocatalyst and H 2 O 2 without any external energy. [6][7][8][9][10][11][12] Since H 2 O 2 is excessively expressed in tumor cells, [13][14][15][16][17][18][19] CDT can not only play an effective role in tumor therapy, but also reduce the damage to normal tissue by ROS. However, highly expressed glutathione in the tumor microenvironment can reduce excess ROS, protecting the tumor cells against damage, [20][21][22] which seriously hinders ROS-based therapy including CDT.…”

Biomimetically constructing a hypoxia-activated programmable phototheranostics at the molecular level

“…39,40 Metal oxide nanoparticles that performed the catalase-like dismutation of H 2 O 2 have been extensively explored as chemodynamic catalysts for this purpose. [41][42][43] Direct use of antioxidant enzymes such as catalase has also been reported; however, the obstacles, including large molecular weight, high expense, low cellular uptake, and easy hydrolytic degradation by the proteases in living cells, need to be overcome. 44,45 To maximize the synergistic action of different ingredients, design of such a combination medicine at the molecular level would be particularly desirable.…”