Role of DNA repair capacity in cadmium induced cellular adaptive response / 中华放射医学与防护杂志

ABSTRACT

Objective To investigate cadmium induced adaptive responses (AR) to either toxicant challenge or irradiation and also the role of PI3K family in the AR. Methods Cells were pre-treated with 0.1 or 1 μmol/L cadmium and then challenged by 50, 100 μmol/L cadmium or 1, 2 Gy γ-rays irradiation. Micronucleus induction was measured to evaluate the magnitude of AR. In some experiments, cells were treated with wortmannin during and after pretreatment. Results Cadmium of sub-lethal concentration could induce AR in all the cells toward 50 μmol/L cadmium or 1 Gy irradiation. When challenged by 50 μmol/L CdCl1, EM-C11 cells had an AR less apparent than the other two cell lines. Moreover, treatment of cells with wortmannin eliminated the AR in all three cell lines. Conclusions The magnitudes of AR in adapted cells may be related to multiple factors, such as DNA repair capacity, the priming and challenging dose of cadmium or irradiation. SSB rather than DSB repair is mainly involved in the cadmium induced AR and this cellular response may be mediated through ATM pathway.