Systematic identification of cancer cell vulnerabilities to natural killer cell-mediated immune surveillance

Abstract

12Only a subset of cancer patients respond to T-cell checkpoint inhibitors, highlighting the need for 13 alternative immunotherapeutics. We performed CRISPR-Cas9 screens in a leukemia cell line to 14 identify perturbations that enhance natural killer effector functions. Our screens defined critical 15 components of the tumor-immune synapse and highlighted the importance of cancer cell 16 interferon-g signaling in modulating NK activity. Surprisingly, disrupting the ubiquitin ligase 17 substrate adaptor DCAF15 strongly sensitized cancer cells to NK-mediated clearance. DCAF15 18 disruption induced an inflamed state in leukemic cells, including increased expression of 19 lymphocyte costimulatory molecules. Proteomic and biochemical analysis revealed that cohesin 20 complex members were endogenous client substrates of DCAF15. Genetic disruption of DCAF15 21 was phenocopied by treatment with indisulam, an anticancer drug that functions through DCAF15 22 engagement. In AML patients, reduced DCAF15 expression was associated with improved 23 survival. These findings suggest that DCAF15 inhibition may have useful immunomodulatory 24 properties in the treatment of myeloid neoplasms. 25 26 T and NK cells share effector functions, releasing cytokines and exocytosing lytic granules upon 58 activation to kill target cells. However, NK activation status is controlled by the integrated signals 59 from germline-encoded NK-activating and -inhibiting receptors (aNKRs/iNKRs). Generally, 60 iNKR ligands are expressed by normal and healthy cells, whereas aNKR ligands are upregulated 61 after DNA damage or viral insult 19,20 . MHC-I molecules provide a potent inhibitory signal sensed 62 by NK cells, enabling the innate immune system to respond productively to MHC-deficient cells. 63As a result, there is considerable interest in amplifying NK responses to cancers, as well as 64 developing NK-based cell therapies [18][19][20] . 65 66 Here, we performed genetic screens in an MHC-deficient leukemic cell line to systematically 67 identify modulators of NK-mediated anti-cancer immunity. These screens, unexpectedly, revealed 68 the potential therapeutic utility of targeting the CRL4 substrate adaptor DCAF15 in myeloid 69 malignancies. Disruption of DCAF15 strongly sensitized cancer cells to NK-mediated killing, 70 resulting from increased cancer cell expression of lymphocyte costimulatory molecules. Proteomic 71 experiments revealed that DCAF15 interacted with and promoted the ubiqitination of the cohesin 72 complex members. Treatment with indisulam, an anticancer drug that modulates DCAF15 73 function, reduced interaction with cohesin members and mimicked DCAF15 loss-of-function 74 immunophenotypes. 75 76 Results 77 78 A genome-scale CRISPR screen identifies modulators of NK effector functions 79 80We performed genome-scale CRISPR screens in K562 cells to identify perturbations that modulate 81 NK-92-mediated killing ( Figure 1A). K562 human chronic myelogenous leukemia cells are a NK-82 sensitive cancer cell line that weakly expresses MHC-...

Transcriptome meta-analysis reveals differences of immune profile between eutopic endometrium from stage I-II and III-IV endometriosis independently of hormonal milieu

“…Additionally, among common DEGs in stage I-II endometriosis, several of them are relative to inflammatory and/or infectious process. ZNF580 is potentially involved in the modulation of inflammatory process 141 ; DCAF15 is potentially involved in the immune surveillance 142 ; BANF1 is involved in the immunity against integration of foreign DNA and response to DNA damage 143 , and it is required to maintain undifferentiated phenotype of the stem cells 144 ; HECTD3 is associated to the modulation of host defense against infection 145 ; SSC5D, which is a soluble receptor produced by macrophages, T cells, and epithelial cells from placenta, is upregulated on infection and it has capacity to interact with bacteria 146 ; TEFB has a role in the autophagy and in the regulation of inflammasome 147 ; CD74 plays a role in the macrophage recruitment, adhesion and migration 148 . Despite the debatable utility of the biomarkers as noninvasive tool to diagnosis endometriosis 149,150 , these differences in transcript levels should be investigated further, at least as a driver to understand its pathophysiology.…”

PBRM1 and the glycosylphosphatidylinositol biosynthetic pathway promote tumor killing mediated by MHC-unrestricted cytotoxic lymphocytes

“…Most of the genes isolated in the screens, however, were not previously linked to tumor killing. Notably, most of our hits including PBRM1 and GPI biosynthetic genes were not recovered in previous attempts to genetically dissect NK cell-mediated killing (56)(57)(58), likely because of the unique genetic screening platform used in this work. The advantages of this platform include homogeneous populations of CLs with consistent tumor-killing activities and a multiround selection procedure that can identify genes with a wide range of KO phenotypes.…”

Fish Galectin8-Like Exerts Positive Regulation on Immune Response Against Bacterial Infection

“…Previous study shows that galectins bind to bacteria through the carbohydrates on bacterial cell wall, which can be competitively inhibited by another carbohydrates ( 24 ). So several saccharides including lipopolysaccharide (LPS), lipoteichoic acid ( 25 ), galactose, mannose, and maltose were chosen to explore the inhibitory capacities on the binding activity of rOnGal8L to bacterial through competitive binding assay. The rOnGal8L or GST-tag protein (1 mg/mL, 10 μL) was incubated with each saccharide (1 mg/mL, 50 μL) and 500 μL of S. agalactiae and A. hydrophila at room temperature for 1 h and incubated mixtures were examined by western blot as described above.…”