Fig. 4

Elevated ID2 expression correlates with poor patient outcome. a,b Tukey plots representing the expression of ID2 and ALDH3A1 in the TCGA datasets based on receptor status. Box indicates the first and third quartiles, the bar indicates the median, whiskers indicate 1.5 interquartile range (IQR), and dots indicate outliers. The number of samples is shown in parentheses. a Adjusted p values determined using one-way ANOVA followed by Tukey’s multiple comparisons test. **p < 0.01, *p < 0.05. b p values determined using Mann-Whitney test (p < 0.0016 for ID2, p < 0.0028 for ALDH3A1). c Kaplan-Meier analysis of breast cancer-specific distance metastasis-free survival (DMFS) in the 218 oestrogen receptor (ER)-negative tumours of the Gyorffy et al. dataset [13]. The number of samples in each group, hazard ratios (HR), and log rank Mantel-Cox p values are shown. d Kaplan-Meier analysis of brain metastasis relapse-free survival (RFS) in the cohort of 104 ER-negative tumours from patients who had either no metastatic relapse or brain-only relapse (see Methods). HR and log rank Mantel-Cox p values are shown. e Comparison of ID2 expression in primary breast cancers and breast cancer brain metastases (BCBM) in the Schulten et al. [15] (left panel) and Harrell et al. [16] (right panel) datasets. The number of samples is shown in parentheses. Data represent normalised expression values ± SEM. HER2 human epidermal growth factor 2, ns not significant, TN triple-negative