Heat shock factor 1 (HSF1) is a transcription factor controlling the process of stress, shock response, development and many other biological processes by inducing the expression of heat shock proteins (HSPs).21, 22 Heat shock factor 1 is also activated in breast cancer tissue, and its high expression level is associated with poor prognosis of breast cancer.23, 24 Clearly, both FAM3C and HSF1 are important biomarkers and potential targets for the diagnosis and treatment of breast cancer. This evidence concerns the gene FAM3C and breast cancer.