Low-dose exposure to gamma rays induces specific gene regulations in normal human keratinocytes.

Skin is the organ most exposed to various environmental aggressors, including ionizing radiation. Low-dose and low-dose-rate exposures to gamma rays account for most occupational, medical or environmental irradiations. To examine whether this type of exposure triggers specific molecular responses, cultured primary keratinocytes isolated from adult normal skin were irradiated with single acute doses of 1 cGy or 2 Gy.

Activation of an energy providing response in human keratinocytes after gamma irradiation.

We performed a microarray study on human differentiated HaCaT keratinocytes exposed to ionizing radiation (2 or 10 Gy). At 3 h after exposure, more than 150 known and unknown genes were found regulated in irradiated HaCaT keratinocytes. Among the genes regulated at 3 h, those involved in cell energy metabolism appeared to be the most abundant and the most responsive.