Interleukin-37 gene expression is down-regulated in patients with acute myeloid leukemia and shown to be affected by CD14 and HLA-DR immunophenotypes

Abstract

Recent evidence has indicated that interleukin 37 (IL-37) shows down-regulated expression in patients with acute myeloid leukemia (AML), but its association with immunophenotypic markers has not been explored. In the current study, IL37 mRNA expression was analyzed in the peripheral blood of 131 AML patients and 100 controls using the 2–ΔΔCt method (fold change), which was based on the principles of quantitative real-time polymerase chain reaction. AML patients were characterized in terms of gender, therapy, fms-like tyrosine kinase 3/internal tandem duplication (FLT3/ITD) and nucleophosmin 1 (NPM1) mutations, French-American-British classification (FAB), World Health Organization (WHO) classification, and immunophenotypes of 25 cytoplasmic and surface markers. IL37 mRNA expression was given as median and interquartile range. Low expression of IL37 mRNA (0.273 [0.062–0.456]) was found in AML patients. This reduced expression was more pronounced in females than in males but the difference was significant before the Bonferroni correction (0.196 [0.045–0.411] vs. 0.4 [0.153–0.466]; probability [p] = 0.008; corrected p = 0.064). In addition, the FAB M4 type (0.109 [0.031–0.269]) and the WHO PML-RARA type (0.171 [0.061–0.482]) had the lowest expression of IL37 mRNA among the other types. For immunophenotypes, only two significant differences were found. First, CD14-positive patients showed a lower level of expression than CD14-negative patients (0.146 [0.033–0.413] vs. 0.323 [0.108–0.468]; p = 0.02). Second, HLA-DR-positive patients showed a higher level of expression than HLA-DR-negative patients (0.325 [0.163–0.474] vs. 0.214 [0.045–0.42]; p = 0.04). However, the corrected p-value was not significant in both cases (p > 0.05). In conclusion, IL37 mRNA expression was down-regulated in AML patients, especially females, and those with the FAB M4 type and the WHO PML-RARA type. This expression may be affected by the immunophenotypic markers CD14 and HLA-DR.