[Increased serum IL-6 and soluble IL-6 receptor in breast cancer patients after radiotherapy are correlated with proportions of immune cells]

Abstract

Objective To investigate the value of serum interleukin-6 (IL-6) and soluble interleukin-6 receptor (sIL-6R) levels of breast cancer patients in evaluating immune function after radiotherapy. Methods We randomly selected 55 cases of breast cancer patients who had received radiotherapy as an observation group, and 55 cases of normal healthy adults as a control group. ELISA was used to detect serum IL-6 and sIL-6R levels. Flow cytometry was used to detect CD45⁺CD19⁺ B lymphocytes, CD45⁺CD3⁺CD4⁺ T lymphocytes, CD45⁺CD3⁺CD8⁺ T lymphocytes and CD45⁺CD16⁺CD56⁺ NK cells in peripheral blood. The correlation of lymphocyte subsets with IL-6 or sIL-6R levels was analyzed. Results Serum IL-6 and sIL-6R levels of the observation group patients after radiotherapy were significantly higher than those before radiotherapy and in the control group, and the IL-6 and sIL-6R levels of patients of III or IV stage breast cancer increased significantly. Flow cytometry showed that the ratios of total T lymphocytes and NK cells in the observation group after radiotherapy were significantly reduced, while the ratio of B lymphocytes was significantly elevated. In addition, the levels of IL-6 and sIL-6R were positively correlated with the ratio of NK cells and negatively correlated with the ratio of B lymphocytes. Conclusion Serum IL-6 and sIL-6R levels in patients with breast cancer can be used as references for assessing the course of breast cancer and immune function after radiotherapy.