Radiation-induced adaptive response with reference to evidence and significance: A review.

In contradiction to classical paradigm, which assumes that radiation effectsare directly proportional to energy deposit, numerous studies described theexistence of a radiation-induced adaptive response, according to whichpre-exposure to low priming dose of ionizing radiations decreases thebiological effects of a subsequent higher challenging dose. Initiallycharacterized in human lymphocytes, this phenomenon has since then beenidentified in a great variety of in vitro and in vivo models. Although fewis known about molecular mechanisms implicated in radiation-induced adaptiveresponse, DNA repair and p53-related pathways seem to play an importantrole. This mini-review addresses the current knowledge on in vitro, in vivoand in utero radioadaptive response, its characteristics and itsconsequences for carcinogenesis and risk assessment. Further research inthis area of study may help to better understand bioresponse to low dose ofradiation and build a new paradigm for evaluation of radiation risks