SOX2 and urinary bladder cancer: Kaplan-Meier analysis showed that SOX2, but not SOX4, expression correlated with a poor recurrence-free survival in bladder cancer patients, and the patients harboring a SOX2-high/SOX4-low signature had a worse recurrence-free survival outcome than those with SOX2-low/SOX4-high signature (Fig. 6a–c).