Introduction. Despite significant advances in therapy of patients with chronic myeloid leukemia (CML), improved survival rates, development of resistance to tyrosine kinase inhibitors (TKIs) remains an urgent problem. Aim. To study the correlation between the level of expression of regulatory proteins p53, c-myc, ki-67 and caspase-3 on the bone marrow cells and the concentration of certain pro- and anti-inflammatory cytokines in blood serum with the effectiveness of therapy in patients with CML. Materials and methods. Seventy-four CML patients with chronic phase of the disease receiving TKI therapy were examined. In all patients, the concentration of certain cytokines and growth factors (TNF-α, IL-1β, IL-2, IL-4, IL-6, IL-10, IL-17, IL-18, IFN-α, and VEGF-A) was determined in blood serum by enzyme immunoassay and immunocytochemical study of bone marrow smears with monoclonal antibodies against antigens of regulatory molecules ki-67, p53, c-myc, and caspase-3. To determine the role of the biomarkers in predicting the therapy effectiveness, a comparative analysis of their values in groups of patients with a major molecular response (MMR) (n = 50) and without MMR (n = 24) was performed. Results. A comparative analysis of the expression of regulatory molecules on the bone marrow cells and the blood serum concentration of cytokines and growth factors of CML patients, depending on depth of the response to TKI therapy, showed that patients who did not achieve MMR had a significantly higher level of caspase-3 expression and concentration of pro-inflammatory cytokines IL-1β, IL-2, IL-6 and IL-17, as well as growth factor VEGF-A compared with those in patients with MMR. In turn, the achievement of MMR was characterized by a higher level of expression of regulatory molecules p53 and c-myc, as well as an increase in the IL-10 concentration and a decrease in the IL-1β, IL-2, IL-6 and IL-17 concentration. Analysis of the correlation between the level of expression of regulatory molecules and the single cytokine concentration showed a negative correlation between c-myc and p53 with IL-2, IL-1β, IL-17 and a positive (direct) correlation between c-myc and p53 with IL-10, a positive correlation between caspase-3 and IL-2, IL-1β, IL-6, IL-17 and a negative correlation between caspase-3 and IL-10. Thus, the achievement of MMR in patients with CML is more likely with a higher expression of regulatory molecules c-myc and p53 on the bone marrow cells, low expression of caspase-3, and low serum concentrations of IL-2, IL-1β, IL-17, IL-6 and a high concentration of IL-10, which indicates synergism of the biomarkers in the pathogenesis of CML and its tumor progression. The ROC analysis results showed the high quality of predictive models characterizing the achievement of MMR at the level of expression of c-myc > 6%, p53 > 4% in the bone marrow, which correlates with a low serum concentrations of IL-2, IL-1β, IL-17 and a high concentration of IL-10, and indicates the possibility of using these indicators as potential biomarkers of effectiveness of CML therapy and achievement of MMR. Conclusion. The results of the study showed that the concentration of cytokines in the blood serum of CML patients correlates with the intensity of expression of c-myc, p53 and caspase-3 proteins and is important in predicting the effectiveness of therapy.
Read full abstract