ATM and cancer: ATM mRNA itself is also targeted by some miRNAs up-regulated in cancer, such as the N-myc-induced miR421 (Hu et al., 2010; Mansour et al., 2013), but also miR101 (Yan et al., 2010) and miR100 (Ng et al., 2010) whose overexpression enhances radiosensitivity by down-regulating ATM.