GSTK1 and bladder transitional cell carcinoma: Lower expression of GSTK1 was associated with worse 5-year survival in BLCA (50% vs. 37%, p < 0.05), KIRP (83% vs. 58%, p < 0.001), BRCA (86% vs. 65%, p < 0.001), and HNSC (50% vs. 27%, p < 0.001).