Hypersensitivity to very-low single radiation doses: Its relationship to the adaptive response and induced radioresistance

Low-Dose Fractionated Radiation Potentiates the Effects of Cisplatin Independent of the Hyper-Radiation Sensitivity in Human Lung Cancer Cells

“…These observations are contrary to the reports that radioresistant cells express increased HRS/IRR (32). In fact, the most pronounced HRS was shown in the most radiosensitive H-157 cells, suggesting that HRS is not an exclusive phenomenon for radioresistant tumor cells.…”

“…Similar results were obtained by Marples and Skov (35) in CHO cells, as cisplatin increased resistance to subsequent low-dose radiation exposures by abolishing HRS. Because H-157 cells showed HRS, it is likely that a DNA-damaging agent such as cisplatin can trigger the repair mechanisms so that HRS is lost and IRR is induced when cells are exposed to subsequent doses of radiation (32,36). Alternatively, both cisplatin and radiation may target the same subpopulation of the cells.…”

Radiobiological Response of Cervical Cancer Cell Line in Low Dose Region: Evidence of Low Dose Hypersensitivity (HRS) and Induced Radioresistance (IRR)

“…Previously, The HRS/IRR response has been studied in SiHa cell line that showed no evidence of HRS [9].The transition dose was found to be 28 cGy for Co60 beam, 25 cGy for 6 MV and 40 cGy for 15 MV photon. The cellular effects of ionizing radiation were described initially by Puck and Marcus [10][11][12].…”

Current Importance and Potential Use of Low Doses of Gamma Radiation in Forest Species

“…There is evidence that different stress conditions can activate similar defense mechanisms in biological systems (Joiner et al, 1996;1999;Babu et al, 2003). The AR probably involves the transcription of many genes and the activation of numerous signaling pathways that trigger cell defenses more efficient detoxification of free radicals, DNA repair systems, induction of new proteins in irradiated cells with a conditioning dose, and enhanced antioxidant production (Wolff, 1998;Mendez-Alvarez et al, 1999;Pajovic et al, 2001;Assis et al, 2002;Chankova & Bryant, 2001;Coleman et al, 2005;Lanza et al, 2005).…”

“…The AR probably involves the transcription of many genes and the activation of numerous signaling pathways that trigger cell defenses more efficient detoxification of free radicals, DNA repair systems, induction of new proteins in irradiated cells with a conditioning dose, and enhanced antioxidant production (Wolff, 1998;Mendez-Alvarez et al, 1999;Pajovic et al, 2001;Assis et al, 2002;Chankova & Bryant, 2001;Coleman et al, 2005;Lanza et al, 2005). There is evidence that DNA repair underlies the AR induced by low radiation doses in human and plant cells (Lambin et al, 1994;Patra et al, 2003) by increasing the amount and rate of DNA repair (Joiner et al, 1996;1999). It has been proposed that these effects could be related to the induction of an AR.…”