DGKα Enhances Tumorigenic Activity in Bladder Cancer Patients With Chronic Kidney Disease.

INTRODUCTION: Chronic kidney disease (CKD) is a risk factor for bladder cancer (BC) and is reportedly involved in its recurrence and progression. This study aimed to determine the molecular mechanisms underlying the development of BC in patients with CKD. METHODS: First, we generated the CKD mouse model according to a unilateral two-stage renal ischemia-reperfusion injury protocol using wild-type C57BL/6 mice. Second, we conducted a molecular functional analysis of DGKα in BC and investigated the contribution of DGKα to cell invasion, migration, and proliferation activity using human BC cell lines. RESULTS: After confirming elevated serum creatinine levels in mice, the bladder was dissected, and mRNA sequencing of bladder urothelial cells was conducted. Gene expression profiling revealed remarkable upregulation in diacylglycerol kinase alpha (DGKα) level compared to that in control urothelial cells. DGKα-knockdown cells displayed significantly decreased invasion, migration, and proliferation activity compared to the controls. Next, we conducted a clinical analysis of DGKα in BC patients and performed immunohistochemistry (IHC) on samples from patients treated with radical cystectomy. IHC staining revealed that DGKα-positive cases had significantly worse recurrence-free and cancer-specific survival rates (p = 0.036 and = 0.003, respectively). CONCLUSION: DGKα expression is associated with tumorigenic activity in BC. Therefore, it is speculated that increased expression of DGKα in CKD cases is involved in the malignant potentials in BC. In conclusion, the crucial role of DGKα in BC is suggested, and it may be one of the factors contributing to poor prognosis in BC patients with CKD.