In addition to its role in BC tumorigenesis and chemosensitivity, our work brings new insights into the role of RNF168, as it indicates that RNF168 not only participates in DDR signalling, as shown previously (Doil et al, 2009; Pinato et al, 2009; Stewart et al, 2009; Ismail et al, 2010; Ginjala et al, 2011; Gatti et al, 2012; Mattiroli et al, 2012; Bohgaki et al, 2013; Chen et al, 2013; Fradet‐Turcotte et al, 2013; Leung et al, 2014; Kocylowski et al, 2015), but is also involved in H2AX stability under chronic stress. This evidence concerns the gene H2AX and breast cancer.