Oxidative Stress in Hadrontherapy

Abstract

Conventional radiotherapy has shown its efficiency since decades with large progresses during the 1990s. However, for 15-20% of treated patients, there is no prognosis improvement either due to tumor radiation resistance and/or to side effects on normal tissues representing the limiting dose given during a radiotherapy protocol. A new modality of radiation therapy has emerged representing a technological breakthrough: hadrontherapy. This regroups mainly proton and carbon ion therapy. Dose deposit is in favor of hadrons compared to photons as it occurs at a precise depth in human body sparing upstream and downstream normal tissues. Mechanisms of action of photons and hadrons are different. When photons mainly act by water radiolysis-producing e − aq , H • , • OH, H 2 O 2 , O 2 •− …, carbon ions and protons mainly act by direct effects, i.e. by direct transfer of ion energy to biological macromolecules. Moreover, efficiency of carbon ions is considered threefold higher (1.1 for protons) than X-rays in killing tumor cells, whereas it is considered lower for normal cells. These findings suggest strong advantages of hadrontherapy compared to conventional radiotherapy. However, some recent studies tend to show a stronger increase in oxidative stress in normal cells after protons or carbon ions than X-rays.

Differential normal skin transcriptomic response in total body irradiated mice exposed to scattered versus scanned proton beams

“…Indeed, heterogeneity can occur in the lateral penumbra due to the variety of tissues encountered 5 . Moreover, to treat the entire volume of a tumor, Bragg peaks have to be added (SOBP, Spread-Out Bragg Peak) thus resulting in an increase in the dose received upstream of the tumor where plateau phases are also added 6 . In addition, PT can be delivered by two different techniques: passive scattering or active scanning.…”

Multi-omics strategy reveals potential role of antimicrobial resistance and virulence factor genes responsible for Simmental diarrheic calves caused by Escherichia coli

“…The acetyl-11-keto-beta-boswellic acid is known to exhibit potent anti-inflammatory properties in vitro and in vivo ( 106 ). The 11-deoxy-16,16-dimethyl prostaglandin E2 was confirmed to protect against oxidative stress ( 107 ), which is responsible for a variety of degenerative processes including diarrhea ( 108 ). Limonene-1,2-epoxide is one derivative of limonene that is associated with diarrhea ( 109 ).…”

Biological Effects of Scattered Versus Scanned Proton Beams on Normal Tissues in Total Body Irradiated Mice: Survival, Genotoxicity, Oxidative Stress and Inflammation

“…Associated or not with surgery, this therapy often allows definitive control of the tumor [1,2]. However, about 15-20% of the patients treated by RT, prognosis is not improved [3] of RT go to failure. These failures depend on different parameters: (i) characteristics of the tumor (volume, cell kinetics, radiosensitivity, repair capacity), (ii) its environment (hypoxia, proximity of organs at risk) [4,5] and (iii) the radiation sensitivity of surrounding healthy tissues [6].…”