Parameters of local cellular immunity in patients with bladder cancer.

Abstract

e16508 Background: Bladder cancer (BC), which accounts for 4.5% of the total cancer incidence, is the cause of frequent severe disability and a significant deterioration in the quality of life of patients. BC development is determined by a number of factors, involving the immune system; however, its role is poorly understood. The purpose of the study was to determine characteristics of parameters of the cellular immunity in patients with non-muscle invasive BC. Methods: The study included 14 patients with newly diagnosed stage I BC. Patients were divided into two groups: with low-grade tumors (LG), n = 7, mean age 57 years; with high-grade tumors (HG), n = 6, mean age 60 years. All patients underwent transurethral resection of the bladder, and tumor tissues (TT, size up to 1.5 cm) and perifocal tissues (PT, at least 0.5 cm from the tumor) were obtained. The specimens were disintegrated to obtain the cell suspension. The relative numbers of the main populations of leukocytes and T- and B-lymphocytes, as well as some subpopulations of T-lymphocytes, were determined using the BD FACSCanto II flow cytometer and a panel of antibodies according to the manufacturer's instructions (Becton Dickinson, USA). Results: Reduction of lymphoid tissue infiltration by 78% was observed in TT in HG patients, compared to the LG group; levels of CD8+ lymphocytes, CD3+CD4-CD8- and CD3+CD4+CD8+ cells, NK- and B-lymphocytes were lower by 27%, 33%, 51%, 45% and 62%, respectively. Levels of Treg in HG TT were 32% lower than in LG. The numbers of activated CD4+, CD8+ cells were unchanged, but TT infiltration by naive lymphocytes of both populations was increased by 28% and 31%, respectively. In HG PT, a decrease in the total number of lymphocytes by 27% was observed, together with higher levels of CD3+CD4+CD8+ cells and NK- and B-lymphocytes by 200%, 213% and 31%, respectively. Conclusions: BC patients with various tumor grades demonstrate different distributions of lymphocyte populations in tumor and perifocal tissues; the functional activity of these cells can both contribute to the disease development and determine the risk of recurrence.