Fig. 1: RBM15 expression and clinical outcomes in BC patients.

a Venn diagram of genes showing significant differential expression between basal and non-basal BC tissues in three independent BC patient cohorts. A univariate test using class comparison analysis in the BRB array tool was performed. b RBM15 mRNA expression (log₂) levels in basal/TNBC patients and non-basal/TNBC patients. c Molecular subtypes of RBM15 in the indicated cohorts. d Gene alteration of RBM15 in the TCGA-BRCA cohort. e–g IHC staining of breast cancer tissue specimens from a TMA slide was performed with an RBM15 antibody. Representative images of IHC staining of the specimens (e, f) and a graph of the results of IHC quantification (g). Student’s t test was applied for statistical significance (*p < 0.05, ***p < 0.005). h, j Patients in the indicated BC cohorts or basal/TNBC-specific cohorts were dichotomized by relatively high or relatively low RBM15 expression and were considered for plotting. The differences between these groups were significant as indicated (log‐rank test). (i, k) ROC curve analysis of the RBM15 expression-related probability of recurrence in the BC cohort (i) and basal/TNBC cohort (k). ROC curve analysis was performed to evaluate the correlation of RBM15 gene expression levels with overall survival by determining the area under the curve (AUC), which was estimated through the concordance index. The corresponding p values were determined using one-sided Wilcoxon signed-rank tests.