SPRY4‐IT1 is up‐regulated in breast cancer stem cells and is correlated with prognosis. A, SPRY4‐IT1 expression in breast cancer patients by in situ hybridization. Original magnification, ×200. Scale bars, 100 μm. B, Kaplan‐Meier survival analysis of breast cancer patients’ overall and disease‐free survival based on SPRY4‐IT1 expression in our cohort (n = 101, P = .0474 and P = .0417, respectively). C, Kaplan‐Meier survival analysis of breast cancer patients’ overall survival based on SPRY4‐IT1 expression by Kaplan‐Meier Plotter (P = .0033). D, mRNA expression level of SPRY4‐IT1 in MCF‐7 cells and MCF‐7 CSCs detected by qRT‐PCR. E, SPRY4‐IT1 mRNA expression level in the CD44+/CD24‐ group and other groups from RNA sequencing data from TCGA‐BRCA database. OCT4(F), ABCC1(G) and ABCG1(H) mRNA expression levels in the SPRY4‐IT1 low expression group and high expression group from RNA sequencing data from TCGA‐BRCA database. *P < .05, **P < .01, ***P < .001, ****P < .0001