Effect of Argon-Helium Cryosurgery on Regulatory T Lymphocytes in the Peripheral Blood of Patients with Advanced Renal Carcinoma

Abstract

Objective:To analyze the effect of Argon-Helium cryosurgery (AHCS) on CD4+ CD25+ regulatory T cells (Treg) and its implication in patients with advanced renal carcinoma. Metbods:,Peripheral venous blood samples were obtained from 32 patients with advanced renal cell carcinoma before and after AHCS. The proportions of Treg cells and T lymphocyte subsets (CD3+ T, CD4+ T, CD8+ T, CD4+ T/CD8+ T, and NK cells) in the peripheral blood were measured by flow cytometry. Enhanced CT or enhanced MRI was used to observe the necrosis of tumor at 1 month after AHCS. The areas with no imaging enhancement in tumor were regarded as tumor necrosis. The necrosis rate was measured by Cavalieri method and the tumor burden was evaluated. Results:At 3 months after AHCS, the percentages of Treg cells were gradually decreased from 4.18%±1.58% to 1.96%±0.54%, with a significant difference (P=0.001). At 3 months after AHCS, the proportions of CD3+ T, CD4+ T, NK and CD4+ T/CD8+ T were gradually increased from 19.26%±7.52%, 43.54%±12.99%, 1.15%±0.57%, and 17.49%±8.36% to 30.83%±5.69%, 49.58±10.76%, 1.84%±0.12%, and 27.63%±8.20%, with a statistical significance (P=0.000, P=0.003, P=0.02, and P=0.001). The proportion of CD8 + T was decreased from 40.86%±8.89% to the lowest ratio (26.74%±4.29%) at 3 months after AHCS, with a significant difference (P=0.000). At 3～6 months after cryotherapy, there was only a slight change in the proportions of CD3 + T, CD4 + T, CD4 + T/CD8 + T, NK, CD8 + T, and Treg cells, with no significant difference (P0.05). Correlation analysis showed that the decrease in tumor burden was positively correlated with the decrease of the proportion of Treg cells (r=0.793, P0.01). Conclusion:After AHCS, the distribution of T-lymphocyte subsets can be improved and the anti-tumor immune response was strengthened. The percentage of Treg cells is correlated with tumor burden.