Recurrence-free survival analysis for CXCR4 using breast cancer data in Kaplan-Meier Plotter Database [35] showed that the upregulation of CXCR4 was associated with poor prognosis (HR = 1.17 (1.05–1.29), p = 0.0029, Fig. 4B). Here, CXCR4 is linked to breast carcinoma.