Since in vitro analyses showed an effect of HSF1 on E2-stimulated cell migration that may facilitate metastasis formation, we checked HSF1 levels in metastatic (defined as all cases with a nonzero number of positive lymph nodes or with distant metastases; 418 cases) and nonmetastatic (399 cases) breast cancers (data deposited in TCGA database). The gene discussed is HSF1; the disease is breast cancer.