To better match the evaluation criteria of HDAC3 in the bc‐GenExMiner database, which contained 4903 breast cancer patients (that database did not state whether HDAC3 was nuclear or cytoplasmic), we classified the cases with high nuclear or cytoplasmic expression of HDAC3 into the C‐high/N‐high group, and other cases were classified into the Others group. This evidence concerns the gene HDAC3 and breast cancer.