Through analysis of the public available breast cancer survival data (http://kmplot.com/analysis/), we observe that RNF168 mRNA level is correlated with poor relapse‐free survival in endocrine treated patients, but not correlated with ER alpha mRNA level (Figures 1D and S1A,B), which might indicate the involvement of RNF168 in regulating oestrogen signalling pathway. Here, ESR1 is linked to breast cancer.