Modification of 10 cGy neutron or gamma-rays induced chromosomal damages by hyperthermia: an in vitro study

ABSTRACT

To evaluate the effects of hyperthermia [HT] on the frequency of chromosomal aberrations induced by a low dose of neutron or gamma-rays in human peripheral blood lymphocytes. Blood samples were exposed to HT [41.5°C for 30 and 60min, 43°C for 15 and 30min], 10 cGy neutron or gamma-rays, HT + neutron/gamma, and neutron/gamma + HT. After standard cell culture, harvesting, fixation and staining, the chromosomal damages were scored in metaphase plates. HT alone at 41.5°C did not induce chromatid or chromosome aberrations, however, the frequency of damages was significantly higher at 43°C [P<0.05]. Furthermore, the chromosomal damages was significantly different when cells were irradiated with neutron or gamma-rays alone [P<0.01]. HT 1 hr post neutron/gamma irradiation significantly induced higher chromosome damages in comparison to HT 1 hr before irradiation [P<0.05]. The chromosomal damages were remarkably higher when cells were irradiated with neutron then heated at 43°C for 30 min. Since increasing frequency of chromosome damages increases probability of cell death, application of HT after neutron irradiation [instead of X-or gamma-rays] might be considered as a procedure for cells killing in radiotherapy