Abstract:

Objective To explore the clinical value of Mg2+ transporter 1（MagT1）expression in peripheral blood CD8 + T lymphocytes in patients with acute myeloid leukemia（AML）. Methods One hundred and nighty⁃ seven new⁃onset AML patients admitted to our hospital from March 2014 to December 2018 and 60 physical exam⁃ iners in the same period were enrolled in the study. Peripheral blood monocytes cells（PBMCs）and CD8 + T cells were isolated. The concentration of serum Mg2+ was detected by automatic biochemical analyzer，and the expression of MagT1 mRNA in PBMCs was detected by RT⁃qPCR. AML patients were divided into low，medium and high risk groups according to NCCN AML guidelines. The expression of MagT1 mRNA and protein in CD8+ T cells were detected by RT⁃qPCR and Western blot. The expression of PD⁃1 and Tim⁃3 was detected by flow cytometry. The correlation between MagT1 protein and the expression of PD⁃1 and Tim⁃3 was analyzed by Spearson correlation assay. The relationship between MagT1 protein expression in CD8+ T cells and event free survival（EFS）and overall survival（OS）were analyzed by Kaplan ⁃Meier curve. Receiver operating characteristic（ROC）curve was used to evaluate the predictive value of MagT1 protein expression level in risk stratification and prognosis of AML patients. Results Compared with the control group，the Mg2+ concentration in peripheral blood of AML patients decreased， and the relative expression of MagT1 mRNA in PBMCs decreased. Compared with the low⁃risk group，the relative expression of MagT1 mRNA and protein in CD8+ T cells in the medium and high⁃risk groups decreased，while the levels of PD⁃1 and Tim⁃3 increased. The expression of MagT1 protein in CD8+ T cells was negatively correlated with the expression levels of PD⁃1 and Tim⁃3. The EFS and OS of patients with high expression of MagT1 protein were higher than those with low expression of MagT1 protein. The expression level of MagT1 has evaluation value for prognosis（AUC = 0.866，95%CI：0.817 ~ 0.915）and risk stratification（AUC = 0.724，95%CI：0.642 ~ 0.806） of AML patients. Conclusion The decreased expression of MagT1 in peripheral blood CD8+ T cells in patients with AML is associated with adverse risk stratification，CD8 + T lymphocyte depletion and adverse survival. It has important value in evaluating the risk and predicting the prognosis of patients with AML.

Key words:

acute myeloid leukemia, CD8+ T lymphocytes, magnesium transporter 1, prognosis