Defective NK cells in AML patients at diagnosis are associated with blast transcriptional signatures of immune evasion. Homo sapiens

Acute myeloid leukemia (AML) is a heterogeneous group of malignancies which may be sensitive to the natural killer (NK) cell anti-tumor response. However, NK cells are frequently defective in AML. Here, we found in an exploratory cohort (n = 46) that NK-cell status at diagnosis of AML separated patients in two groups with a different clinical outcome. Patients with a deficient NK-cell profile, including reduced expression of some activating NK receptors (e.g. DNAM-1, NKp46 and NKG2D) and decreased IFN-g production, had a significantly higher risk of relapse (P = 0.03) independently of cytogenetic classification in multivariate analysis. Patients with defective NK cells showed a profound gene expression decrease in AML blasts for cytokine and chemokine signaling (e.g. IL15, IFNGR1, IFNGR2, CXCR4), antigen processing (e.g. HLA-DRA, HLA-DRB1, CD74) and adhesion molecule pathways (e.g. PVR, ICAM1). A set of 388 leukemic classifier genes defined in the exploratory cohort was independently validated in a multicentric cohort of 194 AML patients. In total, these data evidenced the interplay between NK-cells and AML blasts at diagnosis allowing an immune-based stratification of AML patients independently of clinical classifications. Overall design: Gene expression analysis were performed on CD56bright and CD56dim NK cells sorted from patients with impaired or normal CD56bright NK cells (n=2 for each patients? group) and from 3 HC