The content of cytokines in the blood of patients with various stages of breast cancer

Background. Cytokine homeostasis is an important factor characterizing the general condition and adaptive capabilities of the body of patients with malignant neoplasms. However, the role of various growth factors and their significance in the development and enhancement of malignant growth in breast cancer remain poorly understood.

Aim. To evaluate the levels of cytokines - tumor necrosis factor α, interleukins-4, -6, -8 and -10 — in the blood serum of patients with different stages of breast cancer in comparison with healthy volunteers.

Material and methods. The study was conducted in 65 patients aged 25 to 67 years (mean age 44.5 [40.0–56.5] years). Two groups were distinguished: the first — with stage 1–2, the second — with stage 3–4 of breast cancer. The comparison group consisted of 15 apparently healthy women without cancer, aged 29 to 66 years (mean age 51.0 [39.0–61.0] years). Blood levels of tumor necrosis factor α, interleukins-4, -6, -8 and -10 were studied by enzyme immunoassay. The obtained data were processed using the methods of variation statistics, the Statistica 10.0 software package. The significance of differences was assessed by calculating the median and interquartile interval, analysis of variance was performed using the Kruskal–Wallis H-test, and Dan's Q-test was used for multiple comparisons. The critical significance level p for statistical tests was taken equal to 0.05.

Results. In the group of patients with stage 1–2 breast cancer, an increase in the blood levels of all studied cytokines was revealed in comparison with the group of healthy women: interleukin-6 (p=0.00719), interleukin-8 (p=0.00259), tumor necrosis factor α (p=0.00014), interleukin-4 (p1=0.0133), interleukin-10 (p1 <0.00001). In the group of patients with stage 3–4 breast cancer, an increase in blood levels was characteristic of all studied cytokines: interleukin-8 (p=0.00009), tumor necrosis factor α (p=0.000004), interleukin-4 (p <0.00001), interleukin-10 (p <0.00001), except for interleukin-6 (p=0.15608). The established patterns in changes in the content of cytokines in the blood of patients with breast cancer at different stages of development can serve as the basis for developing approaches to the diagnosis and treatment of the disease.

Conclusion. In patients with breast cancer, the levels of tumor necrosis factor α, interleukins-4, -6, -8, -10 (p <0.05) are higher than in healthy women.