title: Impairing the radioresistance of cancer cells by hydrogenated nanodiamonds.
abstract: Hydrogenated nanodiamonds (H-NDs) exhibit a negative electron affinity that confers a high reactivity with oxygen species and a positive charge in aqueous solutions. It allows electron emission from H-NDs following irradiation by photons and in consequence may enhance the effects of radiation on cancer cells. By using three human radioresistant cancer cell lines, we showed a potentialization of cytotoxicity after a co-exposure to H-NDs and irradiation; an event occurring through the induction of DNA damage and reactive oxygen species. This occurred together with a decrease in cell impedance, the activation of G1/S, an unlocking of G2 cell cycle check-points and early low cell death rate. At later stage of exposure, persistent increases in heterochromatinization, large γ-H2AX foci and β-galactosidase activity were detected providing evidence of cells' entrance into senescence. Similar potentialization was observed with neocarzinostatin (NCS), a radiomimetic drug. This original finding underlines a wide clinical potential of H-NDs to intensify radiation effects on radio-resistant cancer cells.
authors.affiliation: Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), IRCM, Laboratory of Experimental Cancerology (LCE), Fontenay aux Roses, France. Electronic address: romain.grall@cea.fr.
authors.forename: Romain
authors.initials: R
authors.lastname: Grall
authors.affiliation: Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), LIST, Diamond Sensors Laboratory, Gif-sur-Yvette, France. Electronic address: hugues.girard@cea.fr.
authors.forename: Hugues
authors.initials: H
authors.lastname: Girard
authors.affiliation: Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), IRCM, Laboratory of Experimental Cancerology (LCE), Fontenay aux Roses, France. Electronic address: lina2321986@hotmail.com.
authors.forename: Lina
authors.initials: L
authors.lastname: Saad
authors.affiliation: Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), LIST, Diamond Sensors Laboratory, Gif-sur-Yvette, France. Electronic address: tristan.petit@helmholtz-berlin.de.
authors.forename: Tristan
authors.initials: T
authors.lastname: Petit
authors.affiliation: Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), LIST, Diamond Sensors Laboratory, Gif-sur-Yvette, France. Electronic address: celine.gesset@cea.fr.
authors.forename: Céline
authors.initials: C
authors.lastname: Gesset
authors.affiliation: Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), LIST, Diamond Sensors Laboratory, Gif-sur-Yvette, France. Electronic address: mathilde.combis-schlumberger@centraliens.net.
authors.forename: Mathilde
authors.initials: M
authors.lastname: Combis-Schlumberger
authors.affiliation: Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), IRCM, Laboratory of Experimental Cancerology (LCE), Fontenay aux Roses, France. Electronic address: vincent.paget@cea.fr.
authors.forename: Vincent
authors.initials: V
authors.lastname: Paget
authors.affiliation: Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), IRCM, Laboratory of Experimental Cancerology (LCE), Fontenay aux Roses, France. Electronic address: jozo.delic@cea.fr.
authors.forename: Jozo
authors.initials: J
authors.lastname: Delic
authors.affiliation: Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), LIST, Diamond Sensors Laboratory, Gif-sur-Yvette, France. Electronic address: jean-charles.arnault@cea.fr.
authors.forename: Jean-Charles
authors.initials: JC
authors.lastname: Arnault
authors.affiliation: Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), IRCM, Laboratory of Experimental Cancerology (LCE), Fontenay aux Roses, France. Electronic address: sylvie.chevillard@cea.fr.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Chevillard
mesh_terms: D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects*; D006801:Humans; D006859:Hydrogen / Q000737:chemistry*; D008422:Materials Testing; D058612:Nanodiamonds / Q000008:administration & dosage* / Q000737:chemistry / Q000648:ultrastructure; D009374:Neoplasms, Experimental / Q000473:pathology / Q000532:radiotherapy*; D011836:Radiation Tolerance / Q000187:drug effects*; D011838:Radiation-Sensitizing Agents / Q000008:administration & dosage / Q000138:chemical synthesis*; D016896:Treatment Outcome
chemical_list: D058612:Nanodiamonds; D011838:Radiation-Sensitizing Agents; D006859:Hydrogen
keywords: Hydrogenated nanodiamonds (H-NDs); Oxidative stress; Radiation sensitization; Senescence; γ-H2AX