RESUMO
BACKGROUND: Telomerase activity plays a crucial role in cancer development and progression. Thus, telomerase activation through the interplay of mutations and epigenetic alterations in the telomerase reverse transcriptase (TERT) promoter may provide further insight into bladder cancer induction and progression. METHODS: In this study 100 bladder tumour tissues were selected, and four molecular signatures were analysed: THOR methylation status, TERT promotor mutation, telomere length, and TERT expression. RESULTS: In our study, 88% of bladder cancer patients had an hypermethylation of the THOR region and 60% had mutations in the TERT promoter region. TERT promoter methylation was observed in all stages and grades of bladder cancer. While, TERT promoter mutations were detected in advanced stages and grades. In our cohort, high levels of TERT expression and long telomeres have been found in noninvasive cases of bladder cancer, with a significant association between TERT expression and Telomere length. Interestingly, patients with low TERT expression and cases with long telomeres had significantly longer Disease-free survival and overall survival. CONCLUSION: The methylation and mutations occurring in the TERT promoter are implicated in bladder carcinogenesis, offering added prognostic and supplying novel insight into telomere biology in cancer.