TERT Promoter Mutation as a Potential Predictive Biomarker in BCG-Treated Bladder Cancer Patients.

Telomerase reverse transcriptase gene promoter (TERTp) mutations are recognized as one of the most frequent genetic events in bladder cancer (BC). No studies have focused on the relevance of TERTp mutations in the specific group of tumors treated with Bacillus Calmette-Guérin (BCG) intravesical therapy. Methods - 125 non muscle invasive BC treated with BCG therapy (BCG-NMIBC) were screened for TERTp mutations, TERT rs2853669 single nucleotide polymorphism, and Fibroblast Growth Factor Receptor 3 (FGFR3) hotspot mutations. Results - TERTp mutations were found in 56.0% of BCG-NMIBC and were not associated with tumor stage or grade. FGFR3 mutations were found in 44.9% of the cases and were not associated with tumor stage or grade nor with TERTp mutations. The TERT rs2853669 single nucleotide polymorphism was associated with tumors of higher grade. The specific c.1-146G>A TERTp mutation was an independent predictor of nonrecurrence after BCG therapy (hazard ratio-0.382; 95% confidence interval-0.150-0.971, p = 0.048). Conclusions - TERTp mutations are frequent in BCG-NMIBC and -146G>A appears to be an independent predictive marker of response to BCG treatment with an impact in recurrence-free survival.

International journal of molecular sciences. 2020 Jan 31*** epublish ***

Rui Batista, Luís Lima, João Vinagre, Vasco Pinto, Joana Lyra, Valdemar Máximo, Lúcio Santos, Paula Soares

Instituto de Investigação e Inovação em Saúde (i3S), 4200-135 Porto, Portugal., Grupo de Patologia e Terapêutica Experimental, Instituto Português de Oncologia do Porto FG, EPE (IPO-Porto), 4200-072 Porto, Portugal., Instituto de Patologia e Imunologia Molecular da Universidade do Porto (IPATIMUP), 4200-135 Porto, Portugal.