FZD2 and breast cancer: High FZD2 expression is associated with tumor progression in various cancers (38–40).For example, the Wnt5a/FZD2 signaling pathway is critical for resistance to the androgen receptor antagonist enzalutamide in prostate cancer (41, 42); FZD2 activates the Notch signaling pathway to promote TGF-β-induced EMT in breast cancer (43); and WNT2 stabilizes STAT3 signaling through FZD2, modulating metastasis in esophageal cancer.