In ER+/HER2- BC, PEDF had greater anti-metastatic action in the presence of circulating E1, E2, and E1S levels associated with post-menopause, likely because the corresponding intratumoral oestrogen ratios and associated signalling pathways downregulate PEDF to a greater extent than those present in pre-menopausal BC. The gene discussed is SERPINF1; the disease is breast cancer.