INFLUENCE OF P16 GENE METHYLATION ON THE RISK OF PROGRESSION OF NON-MUSCLE INVASIVE BLADDER CANCER

To accurately predict the tumor behavior and individualize the treatment approach, new methods for bladder cancer (BC) prognosis are required. The most promising prognostic markers are the mutational and epigenetic changes of genes involved in maintaining cellular homeostasis. In the present study, we evaluated the influence of p16 promoter hypermethylation on the risk of recurrence, progression and disease outcome in the group of 158 BC patients. p16 epigenetic changes were found in 11.4 % of urothelial carcinomas and did not depend on clinicоmorphological characteristics. However, in the subgroup of patients with non-muscle invasive tumors, p16 abnormal methylation was significantly associated with smoking, and in the subgroup of patients with muscle-invasive BC, it was linked to a high tumor grade (G3). In the multivariate Cox regression analysis, p16 promoter hypermethylation was an independent predictor for bladder cancer progression (HR 6.84; 95 % CI 1.6–29.9; р = 0.011). The use of the data on the p16 methylation status may improve the accuracy of prognosis of the bladder cancer clinical course and the selection of appropriate treatment strategy.

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