Project description:Natural Killer (NK) cells can target and destroy cancer cells, yet tumor microenvironments typically suppress NK cell recruitment and cytotoxicity. Recent work has demonstrated a novel role for nuclear EGFR (nEGFR) in regulating transcriptional events unique from the kinase domain. Using a novel peptide therapeutic (cSNX1.3) that inhibits retrograde trafficking of EGFR and an EGFR nuclear localization mutant, we discovered that nEGFR suppresses NK cell recruitment and cytotoxicity. RNA-seq analysis of breast cancer cells treated with cSNX1.3 or modified to lack a nuclear localization sequence (EGFRΔNLS) revealed the EGF-dependent induction of NK activating antigens, while kinase inhibition by erlotinib did not impact these genes. Together, the data demonstrate a unique immunomodulatory role for nEGFR.
Project description:Natural killer (NK) cells contribute to immunosurveillance and first-line defense in the control of tumor growth and metastasis diffusion. NKEVs are constitutively secreted, are biologically active, reflect the protein and genetic repertoire of their originating cells and exert anti-tumor activity in vitro and in vivo. NKEVs from tumor-conditioned NK cells interact with naïve NK cells promoting their cytotoxic activity. In cancer NK cells exhibit profound defects in degranulation ability, a status probably reflected by their NKEVs. Hence, NKEVs could contribute to improve cancer therapy by interacting with tumor and/or immune cells at the same time sensing the actual NK cell status in cancer patients. Here we investigated the role of NKEVs in stimulating the immune system and developed an immune enzymatic test (NKExoELISA) to sense the systemic NK cell status by measuring plasma NK-derived exosomes through combined capture of exosomes, expressing typical EV (tsg101) and NK cell (CD56) markers. We analyzed by LC-MS/MS the protein content from NKEVs evaluating proteins differentially expressed in exosomes (NKExo), vescicles (NKMV) and total cell extract (Tot extr) from parental NK cells. Proteomic data confirmed the presence of many EV markers and detected several proteins involved in immune response, cell adhesion and complement biological processes.
Project description:In this study we have compared the proteomic profile of extracellular vesicles (EVs) prepared from primary, human NK cells or the human NK cell lines NK-92 and KHYG-1 cultured for 48hrs in serum-free conditions. EVs were harvested from cells either under resting conditions (culture in IL-15) or upon activation (combination of IL-12, IL-15, and IL-18). In addition, primary NK cells were activated in the presence of anti-CD16-coated beads, and EVs harvested after 48hrs. The aim was to compare their ability to target and kill a variety of tumor cell line-derived spheroids
Project description:The term cancer immunoediting describes the dual role by which the immune system can suppress and promote tumour growth and is divided into three phases: elimination, equilibrium and escape. The role of NK cells has mainly been attributed to the elimination phase. Here we show that NK cells play a role in all three phases of cancer immunoediting. Extended co-culturing of DNA barcoded mouse BCR/ABLp185+ B acute lymphoblastic leukaemia cells with NK cells allowed for a quantitative measure of NK cell-mediated immunoediting. Whereas most tumour cell clones were efficiently eliminated by NK cells, a certain fraction of tumour cells harboured an intrinsic primary resistance. Furthermore, DNA barcoding revealed tumour cell clones with secondary resistance, which stochastically acquired resistance to NK cells. NK cell cytotoxicity put a selective pressure on B-ALL cells inducing primary and secondary resistance, while resistant tumour cells were characterised by a full-blown IFN-g signature. Besides well-known regulators of immune evasion, our analysis of NK resistant tumour cells revealed the upregulation of novel genes, including Ly6a, which we found to drive NK cell resistance in leukaemic cells. We further translated our findings to the human system and showed that high LY6E expression on tumour cells impaired the physical interaction with NK cells and led to worse prognosis in leukaemia. Our results demonstrate that tumour cells are actively edited by NK cells during the equilibrium phase and use different avenues to escape NK cell-mediated eradication.
Project description:The term cancer immunoediting describes the dual role by which the immune system can suppress and promote tumour growth and is divided into three phases: elimination, equilibrium and escape. The role of NK cells has mainly been attributed to the elimination phase. Here we show that NK cells play a role in all three phases of cancer immunoediting. Extended co-culturing of DNA barcoded mouse BCR/ABLp185+ B acute lymphoblastic leukaemia cells with NK cells allowed for a quantitative measure of NK cell-mediated immunoediting. Whereas most tumour cell clones were efficiently eliminated by NK cells, a certain fraction of tumour cells harboured an intrinsic primary resistance. Furthermore, DNA barcoding revealed tumour cell clones with secondary resistance, which stochastically acquired resistance to NK cells. NK cell cytotoxicity put a selective pressure on B-ALL cells inducing primary and secondary resistance, while resistant tumour cells were characterised by a full-blown IFN-g signature. Besides well-known regulators of immune evasion, our analysis of NK resistant tumour cells revealed the upregulation of novel genes, including Ly6a, which we found to drive NK cell resistance in leukaemic cells. We further translated our findings to the human system and showed that high LY6E expression on tumour cells impaired the physical interaction with NK cells and led to worse prognosis in leukaemia. Our results demonstrate that tumour cells are actively edited by NK cells during the equilibrium phase and use different avenues to escape NK cell-mediated eradication.
Project description:The term cancer immunoediting describes the dual role by which the immune system can suppress and promote tumour growth and is divided into three phases: elimination, equilibrium and escape. The role of NK cells has mainly been attributed to the elimination phase. Here we show that NK cells play a role in all three phases of cancer immunoediting. Extended co-culturing of DNA barcoded mouse BCR/ABLp185+ B acute lymphoblastic leukaemia cells with NK cells allowed for a quantitative measure of NK cell-mediated immunoediting. Whereas most tumour cell clones were efficiently eliminated by NK cells, a certain fraction of tumour cells harboured an intrinsic primary resistance. Furthermore, DNA barcoding revealed tumour cell clones with secondary resistance, which stochastically acquired resistance to NK cells. NK cell cytotoxicity put a selective pressure on B-ALL cells inducing primary and secondary resistance, while resistant tumour cells were characterised by a full-blown IFN-g signature. Besides well-known regulators of immune evasion, our analysis of NK resistant tumour cells revealed the upregulation of novel genes, including Ly6a, which we found to drive NK cell resistance in leukaemic cells. We further translated our findings to the human system and showed that high LY6E expression on tumour cells impaired the physical interaction with NK cells and led to worse prognosis in leukaemia. Our results demonstrate that tumour cells are actively edited by NK cells during the equilibrium phase and use different avenues to escape NK cell-mediated eradication.
Project description:Neuroblastomas are tumors of the developing peripheral sympathetic nervous system, which originates from the neural crest. Twenty percent of neuroblastomas show amplification of the MYCN oncogene, which correlates with poor prognosis. The MYCN transcription factor can activate and repress gene expression. To broaden our insight in the spectrum of genes down-regulated by MYCN, we generated gene expression profiles of the neuroblastoma cell lines SHEP-21N and SKNAS-NmycER, in which MYCN activity can be regulated. In this study, we show that MYCN suppresses the expression of Dickkopf-1 (DKK1) in both cell lines. DKK1 is a potent inhibitor of the wnt/beta-catenin signalling cascade, which is known to function in neural crest cell migration. We generated a DKK1 inducible cell line, IMR32-DKK1, which showed impaired proliferation upon DKK1 expression. Surprisingly, DKK1 expression did not inhibit the canonical wnt/beta-catenin signalling, suggesting a role of DKK1 in an alternative route of the wnt pathway. Gene expression profiling of two IMR32-DKK1 clones showed that only a few genes, amongst which SYNPO2, were up-regulated by DKK1. SYNPO2 encodes an actin-binding protein and was previously found to inhibit proliferation and invasiveness of prostate cancer cells. These results suggest that MYCN might stimulate cell proliferation by inhibiting the expression of DKK1. DKK1 might exert part of its growth suppressive effect by induction of SYNPO2 expression. Keywords: DKK1, MYCN, neuroblastoma, Dickkopf
Project description:GM-CSF is involved in immune complex (IC)-mediated arthritis. However, little is known about what is the cellular source of GM-CSF and how it is regulated during IC-mediated inflammation. Using novel GM-CSF reporter mice, we show that NK cells produce GM-CSF during an IC-mediated model of inflammatory arthritis. NK cells promoted STIA in a GM-CSF-dependent manner, as deletion of NK cells and selective removal of GM-CSF production by NK cells abrogated disease. Furthermore, we show that myeloid cell activation by GM-CSF is restrained by induction of JAK/STAT checkpoint inhibitor cytokine-inducible SH2-containing protein, CIS. Myeloid cells from CIS-deficient mice had exaggerated responses to GM-CSF, and these mice develop exacerbated STIA. Our data suggest that tissue NK cells may amplify joint inflammation in arthritis via GM-CSF production and thus represent a novel target in IC-mediated pathology. Endogenous CIS provides a key brake on signaling through the GM-CSF receptor and strategies that boost its function may provide an alternative anti-inflammatory approach.