Kaplan-Meier survival plot revealed that for all estrogen receptor (ER)-negative breast cancer patients treated with chemotherapy, those with a high CUL4A expression in tumor tissues had significantly shorter cancer-specific relapse-free survival (RFS) compared to those with a low CUL4A expression (HR = 1.72, 95% confidence interval 1.11–2.65, p = 0.013) as shown in Figure 6C. This evidence concerns the gene ESR1 and neoplasm.