Au-Pt Nanoparticle Formulation as a Radiosensitizer for Radiotherapy with Dual Effects

Abstract

Background: Radiotherapy occupies an essential position as one of the most significant approaches for the clinical treatment of cancer. However, we cannot overcome the shortcoming of X-rays which is the high value of the oxygen enhancement ratio (OER). Radiosensitizers with the ability to enhance the radiosensitivity of tumor cells provide an alternative to changing X-rays to protons and heavy ion radiotherapy. Materials and Methods: We prepared the Au-Pt nanoparticles (Au-Pt NPs) using a onestep method. The characteristics of the Au-Pt NPs were determined using TEM, HAADF-STEM, elemental mapping images, and DLS. The enhanced radiotherapy was demonstrated in vitro using MTT assays, colony formation assays, fluorescence imaging, and flow cytometric analyses of the apoptosis. The biodistribution of the Au-Pt NPs was analyzed using ICP-OES, and thermal images. The enhanced radiotherapy was demonstrated in vitro using immunofluorescence images, tumor volume and weigh, and hematoxylin & eosin (H&E) staining. Results: Polyethylene glycol (PEG) functionalized nanoparticles composed of the metallic elements Au and Pt were designed to increase synergistic radiosensitivity. The mechanism demonstrated that heavy metal NPs possess a high X-ray photon capture crosssection and Compton scattering effect which increased DNA damage. Furthermore, the Au-Pt NPs exhibited enzyme-mimicking activities by catalyzing the decomposition of endogenous H 2 O 2 to O 2 in the solid tumor microenvironment (TME). Conclusion: Our work provides a systematically administered radiosensitizer that can selectively reside in a tumor via the EPR effect and enhances the efficiency of treating cancer with radiotherapy.

Platinum nanoplatforms: classic catalysts claiming a prominent role in cancer therapy

“…5). 164 Several studies have used Pt-based structures to combine RT and PTT to promote therapeutic synergies [141][142][143]165 where PTT can efficiently alleviate some inherent drawbacks of RT (Fig. 5).…”

Multifunctional high-Z nanoradiosensitizers for multimodal synergistic cancer therapy

“…34 Similar to Au nanoparticles, noble metal nanomaterials with other high-Z elements (e.g., Pt and Ir) have been developed to enhance the efficacy of RT. [35][36][37] For example, Muhammad et al found that HeLa cells treated with dendritic Pt nanomaterials showed a sharp decline in their survival curve when compared with the control group under X-ray irradiation. 38 In addition to the most commonly used high-energy X-rays, some other radioactive sources are also used in tumor RT, such as protons and neutrons.…”

Functionalized Au@Cu-Sb-S Nanoparticles for Spectral CT/Photoacoustic Imaging-Guided Synergetic Photo-Radiotherapy in Breast Cancer

“…What's more, cancer cells that are resistant to radiotherapy could be killed by phototherapy. [8][9][10][11][12] High atomic number (Z) metals, including platinum, 13 gold, [13][14][15] and bismuth, 16 have been successfully used as radiotherapy sensitizers to increase the efficacy of external radiation, a process known as radiosensitization. Gold (Au) is a typical high-Z element that is considered an excellent radiotherapy sensitizer because of its higher mass energy absorption coefficients, which results in amplified radiation dose deposition.…”