SFN inhibits cell proliferation and mammosphere formation of CSCs in TNBC. SFN significantly decreases the expression of cancer-specific CR1 and CRIPTO-3/TDGF1P3 genes. SFN suppresses the expression of stem cell markers Nanog, ALDH1A1, Wnt3, and Notch4. SFN may control CSC malignant proliferation in TNBC via CRIPTO-mediated pathway by inhibiting CRIPTO/Alk4 protein complex formation and suppressing its expression and is thus suitable for the chemoprevention of TNBC. Here, CR1 is linked to cancer.