Shorter Leukocyte Telomere Length Is Associated with Worse Survival of Patients with Bladder Cancer and Renal Cell Carcinoma

Simple Summary Intrinsic telomere shortening promotes tumorigenesis in cells with impaired DNA damage repair mechanisms, as dysfunctional telomeres lead to chromosomal instability. More recent data show that the telomere length of peripheral blood leukocyte (PBL) cells can be a prognostic marker for survival of patients with solid tumors. However, reports on bladder cancer (BC) and renal cell carcinoma (RCC) are not consistent and partly contradictory. Our results show, first, that telomere length is shorter in patients with BC or RCC compared to patients without malignant disease. More importantly, the relative telomere length (RTL) of PBL cells is associated with survival of patients with BC and RCC. Thus, telomere length in PBL cells could be an auxiliary prognostic marker in BC and RCC. Background: Telomeres are protein-DNA complexes at the tips of linear chromosomes. They protect the DNA from end-to-end fusion and exonucleolytic degradation. Shortening of telomeric DNA during aging can generate dysfunctional telomeres, promoting tumorigenesis. More recent data indicate that both short and long telomeres of peripheral blood leukocyte (PBL) cells can serve as prognostic biomarkers for cancer risk and may be associated with survival of patients with solid cancers. Telomere length in PBL cells could also be a potential prognostic biomarker for survival in bladder cancer (BC) or renal cell carcinoma (RCC). Methods: The relative telomere length (RTL) of PBL cells was assessed in patients with BC (n = 144) and RCC (n = 144) by using qPCR. A control population of patients without malignant disease (NC, n = 73) was included for comparison. The correlation and association of RTL with histopathological parameters and overall survival (OS) were evaluated. Results: Patients with BC and RCC had significantly shorter telomeres compared to patients without malignant disease. Within the cancer cohorts, multivariate analysis revealed that short RTL is an independent predictor of worse survival in BC (p = 0.039) and RCC (p = 0.041). Conclusion: Patients with BC and RCC had significantly shorter telomeres compared to the normal population. Shorter RTL in BC and RCC was an independent predictor of reduced survival.