Platinum nanoparticles: an exquisite tool to overcome radioresistance

Abstract

BackgroudSmall metallic nanoparticles are proposed as potential nanodrugs to optimize the performances of radiotherapy. This strategy, based on the enrichment of tumours with nanoparticles to amplify radiation effects in the tumour, aims at increasing the cytopathic effect in tumours while healthy tissue is preserved, an important challenge in radiotherapy. Another major cause of radiotherapy failure is the radioresistance of certain cancers. Surprisingly, the use of nanoparticles to overcome radioresistance has not, to the best of our knowledge, been extensively investigated. The mechanisms of radioresistance have been extensively studied using Deinococcus radiodurans, the most radioresistant organism ever reported, as a model.MethodsIn this work, we investigated the impact of ultra-small platinum nanoparticles (1.7 nm) on this organism, including uptake, toxicity, and effects on radiation responses.ResultsWe showed that the nanoparticles penetrate D. radiodurans cells, despite the 150 nm cell wall thickness with a minimal inhibition concentration on the order of 4.8 mg L−1. We also found that the nanoparticles amplify gamma ray radiation effects by >40%.ConclusionsFinally, this study demonstrates the capacity of metallic nanoparticles to amplify radiation in radioresistant organisms, thus opening the perspective to use nanoparticles not only to improve tumour targeting but also to overcome radioresistance.Electronic supplementary materialThe online version of this article (doi:10.1186/s12645-017-0028-y) contains supplementary material, which is available to authorized users.

Functionalized Nanomaterial Assembling and Biosynthesis Using the Extremophile Deinococcus radiodurans for Multifunctional Applications

“…PtNPs were used to combat radioresistance in D. radiodurans treated by ionizing radiation . Li and colleagues characterized the localization and content of PtNPs in D. radiodurans through various advanced microscopy techniques .…”

“…PtNPs were used to combat radioresistance in D. radiodurans treated by ionizing radiation . Li and colleagues characterized the localization and content of PtNPs in D. radiodurans through various advanced microscopy techniques . The impact of nanoparticles on the response of D. radiodurans to gamma‐ray radiation exposure was investigated and quantified by colony‐forming units analysis .…”

“…Li and colleagues characterized the localization and content of PtNPs in D. radiodurans through various advanced microscopy techniques . The impact of nanoparticles on the response of D. radiodurans to gamma‐ray radiation exposure was investigated and quantified by colony‐forming units analysis . They found that a concentration of ≈4700 NPs/cell PtNPs had no major effects on bacterial growth under normal conditions.…”

“…They found that a concentration of ≈4700 NPs/cell PtNPs had no major effects on bacterial growth under normal conditions. This amount of PtNPs was shown to significantly augment radiation effects after exposure of a dose of 8 kGy gamma rays, which was attributed to the confined production of ROS around PtNPs . The use of gold nanomaterials synthesized by D. radiodurans may overcome the radioresistance of certain tumors, improve tumor targeting, and provide a major breakthrough into radiotherapy.…”

Are platinum nanoparticles safe to human health?

“…Interesting is the fact that platinum nanoparticles slightly, but reproducibly, increased cell death after the exposure to gamma rays. The authors claimed that such an amplification effect was due to the confined production of reactive oxygen species in nano-volumes around nanoparticles which favored the induction of complex damage in biomolecules [41]. A HepG2 liver model was used to characterize the toxicological potential of platinum nanoparticles in in vitro studies.…”