SFRP1 and breast carcinoma: As a reminder, the decrease in SFRP1 expression in non-tumoral (MCF10A) and pre-tumoral (MCF10AT1) breast lesions was inversely correlated with ESR1 expression (Figure 3B and Figure 4B), highlighting the existence of a differential role of SFRP1 with regards to breast cancer stage and molecular subtype.