HLA-G expression is irrelevant to prognosis in patients with acute myeloid leukemia

Human leukocyte antigen (HLA)-G could contribute to escape of cancer cells from host anti-tumor responses, and its potential clinical relevance in various malignancies was also addressed. However, the prognostic value of HLA-G in acute myeloid leukemia (AML) remains debated. In this study, HLA-G expression in malignant blasts was analyzed from 77 de novo AML patients (AML-M2, n=26; AML-M3, n=24; AML-M4, n=10; AML-M5, n=17) with flow cytometry. The proportion of HLA-G expressing blasts varied from 0% to 93.96% (median: 0.42%; 95% CI: 0-89.0%). Blasts with 0.5% or fewer HLA-G expressing were defined as negative according to its expression in normal CD34(+)CD45(+) cells (n=20, range: 0-0.5%; median: 0.13%; 95% CI: 0-0.42%). HLA-G expression status on leukemic blasts was not associated with the clinical parameters such as patient age at diagnosis, sex, sub-type of AML, percentage of blasts at diagnosis. Survival analysis revealed that HLA-G expression status on leukemic blasts is unrelated to the prognosis (p=0.884). The mean overall survival time for the HLA-G negative and positive patients was 20.7 months (95% CI: 16.1-25.3) and 20.1 months (95% CI: 14.3-25.8), respectively. Taken together, our findings indicated that HLA-G expression is of no significance for the prognosis of patients with AML.