Relationship between radiosensitivity, initial DNA damage, apoptosis and gene expression: Between reproducible works and technical artefacts

摘要

Reply to Henriquez-Hemandez et al 'Common genomic signalling among initial DNA damage and radiation-induced apoptosis in peripheral blood lymphocytes from locally advanced breast cancer patients'. The Breast 22 (2013) 28-33.The relationships between radiosensitivity, DNA damage, apoptosis and gene expression are dependent on methodology. However: Most of works demonstrate that radiosensitivity is correlated with unrepaired but not radiation-induced (initial) DNA double-strand breaks (DSB). This was demonstrated with various DSB assays and cellular models.1-2 Cells from ataxia telangi-ectasia (AT), the most hyper-radiosensitive syndrome, show about 40 DSB induced per Gy, like radioresistant controls but systematically more unrepaired DSB than radioresistant controls. This is also the case for BRCA1/2 mutations. With regard to apoptosis, AT like radioresistant fibroblasts do not show apoptosis despite their difference in radiosensitivity and apoptotic bodies in lymphocytes, often technically confused with micronuclei, are not necessarily correlated with radiosensitivity.