Lymphocytes from B-acute lymphoblastic leukemia patients present diferential regulation of the adenosinergic axis depending on risk stratifcation

Abstract

Purpose Although risk-stratifed chemotherapy regimens improve B-cell acute lymphoblastic leukemia (B-ALL) clinical outcome, relapse occurs in a signifcant number of cases. The identifcation of new therapeutic targets as well as prog nostic and diagnostic biomarkers can improve B-ALL patients’ clinical outcomes. Purinergic signaling is an important pathway in cancer progression, however the expression of ectonucleotidases and their impact on immune cells in B-ALL lacks exploration. We aimed to analyze the expression of ectonucleotidases in B-ALL patients’ lymphocyte subpopulations. Methods Peripheral blood samples from 15 patients diagnosed with B-ALL were analyzed. Flow cytometry was used to analyze cellularity, expression level of CD38, CD39, and CD73, and frequency of CD38+∕CD73+, and CD39+∕CD73+ in lymphocyte subpopulations. Plasma was used for cytokines (by CBA kit) and adenine nucleosides/nucleotides detection (by HPLC). Results Comparing B-ALL patients to health donors, we observed an increase of CD4+and CD8+T-cells. In addition, a decrease in CD38 expression in B and Treg subpopulations and an increase in CD39+ CD73+ frequency in Breg and CD8+ T-cells. Analyzing cytokines and adenine nucleosides/nucleotides, we found a decrease in TNF, IL-1β, and ADO concentrations, together with an increase in AMP in B-ALL patients’ plasma. Conclusion: As immunomodulators, the expression of ectonucleotidases might be associated with activation states, as well as the abundance of diferent cellular subsets. We observed a pro-tumor immunity expression profle in B-ALL patients at diagnosis, being associated with cell exhaustion and immune evasion in B-ALL.