ATM and cancer: Accordingly, we have shown that SMOX overexpression further enhances the DNA-PKCs and ATM phosphorylation/activation status induced by IR in FN-RMS cells 3 h post-irradiation, a time interval commonly known to be sufficient for DNA repair in normal but not in cancer cells (Tarnawski et al., 2002; Marcu et al., 2004; Begg et al., 2011).