Dissecting the NK Cell Population in Hematological Cancers Confirms the Presence of Tumor Cells and their Impact on NK Population Function

Natural killer (NK) cells are part of the innate immune system, protects against pathogens and tumor cells and are the main cell effectors of monoclonal antibodies (mAbs) generating antibody-dependent cell cytotoxicity (ADCC). Hence it is relevant to understand NK physiology and status to investigate the biological effect of mAbs in the clinic. The presence of viral-sculpted NK cell populations has already been described, but the presence of cancer-sculpted NK remains unknown. Cancer induces a broad NK cell dysfunction. We investigated the NK cell population by Uniform Manifold Approximation and Projection (UMAP) embed maps in Hodgkin lymphoma (HL) and acute myeloid leukemia (AML) patients at diagnosis and at least 30 days after treatment, which correlates with tumor cell clearance. The NK lineage largely responded to the tumor by generating antitumor NK cells and renewing the population with a subset of immature NK cells. However, we failed to identify specific “memory-like” subsets. Moreover, in patients in relapse we found essentially the same NK populations that at diagnostic, suggesting that NK cells equally respond to the first or second tumor rise. Finally, previous CMV infection largely affects tumor-associated changes in NK population, but the CMV-associated CD57+NKG2C+ NKs do not appear to play any role in tumor immunity.