Project description:Colorectal cancer is treated with antibodies blocking epidermal growth factor receptor (EGF-R) but therapeutic success is limited. EGF-R is stimulated by soluble ligands, which are derived from transmembrane precursors by ADAM17-mediated proteolytic cleavage. In mouse intestinal cancer models in the absence of ADAM17, tumorigenesis was almost completely inhibited and the few remaining tumors were of low grade dysplasia. RNA-Seq analysis demonstrated downregulation of STAT3 and Wnt pathway components. Since EGF-R on myeloid cells, but not on intestinal epithelial cells is required for intestinal cancer and IL-6 is induced via EGF-R stimulation, we analyzed the role of IL-6 signaling. Tumor formation was equally inhibited in IL-6 -/- and sgp130Fc transgenic mice, in which only trans-signaling via soluble IL-6R is abrogated. ADAM17 is needed for EGF-R-mediated induction of IL-6 synthesis, which via IL-6 trans-signaling induces ß-catenin dependent tumorigenesis. Our data reveal the possibility of a novel strategy for treatment of colorectal cancer, which could circumvent intrinsic and acquired resistance to EGF-R blockade.
Project description:Acute and chronic pancreatitis, the latter associated with fibrosis, are multifactorial inflammatory disorders and leading causes of gastrointestinal disease-related hospitalisation, including death. Despite the global health burden of pancreatitis, currently there are no effective therapeutic agents. In this regard, the protease A Disintegrin And Metalloproteinase 17 (ADAM17) mediates inflammatory responses through shedding of bioactive inflammatory cytokines and mediators, including tumour necrosis factor α (TNFα) and the soluble interleukin (IL)-6 receptor (sIL-6R), the latter of which drives proinflammatory IL-6 trans-signalling. However, the role of ADAM17 in pancreatitis is unclear. To address this, Adam17ex/ex mice – which are homozygous for the hypomorphic Adam17ex allele resulting in marked reduction in ADAM17 expression – and their wild-type (WT) littermates were exposed to the cerulein-induced acute pancreatitis model, and acute (1-week) and chronic (20-weeks) pancreatitis models induced by the cigarette smoke carcinogen nicotine-derived nitrosamine ketone (NNK). Our data reveal that ADAM17 expression was upregulated in pancreatic tissues of animal models of pancreatitis. Moreover, the genetic (Adam17ex/ex mice) and therapeutic (ADAM17 prodomain inhibitor; A17pro) targeting of ADAM17 ameliorated experimental pancreatitis, which was associated with a reduction in the IL-6 trans-signalling/STAT3 axis. This led to reduced inflammatory cell infiltration, including T cells and neutrophils, as well as necrosis and fibrosis in the pancreas. Furthermore, upregulation of the ADAM17/IL-6 trans-signalling/STAT3 axis was a feature of pancreatitis patients. Collectively, our findings indicate that the ADAM17 protease plays a pivotal role in the pathogenesis of pancreatitis, which could pave the way for devising novel therapeutic options to be deployed against this disease.
Project description:Macrophages in the tumor microenvironment have a substantial impact on tumor progression. Depending on the signaling environment in the tumor, macrophages can either support or constrain tumor progression. It is therefore of therapeutic interest to identify the tumor-derived factors that control macrophage education. With this aim, we correlated the expression of A Disintegrin and Metalloproteinase (ADAM) proteases, which are key mediators of cell-cell signaling, to the expression of protumorigenic macrophage markers in human cancer cohorts. We identified ADAM17, a sheddase upregulated in many cancer types, as a protein of interest. Depletion of ADAM17 in cancer cell lines reduced the expression of several protumorigenic markers in neighboring macrophages in vitro as well as in mouse models. Moreover, ADAM17–/– educated macrophages demonstrated a reduced ability to induce cancer cell invasion. Using mass spectrometry–based proteomics and ELISA, we identified HB-EGF and AREG, shed by ADAM17 in the cancer cells, as the implicated molecular mediators of macrophage education. Additionally, RNA-Seq and ELISA experiments revealed that ADAM17-dependent HB-EGF ligand release induced the expression and secretion of CXCL chemokines in macrophages, which in turn stimulated cancer cell invasion. In conclusion, we provide evidence that ADAM17 mediates a paracrine EGFR-ligand-chemokine feedback loop, whereby cancer cells hijack macrophages to promote tumor progression.
Project description:Lupus nephritis (LN) often results in progressive renal dysfunction. The inactive Rhomboid 2 (iRhom2) is a newly identified key regulator of A disintegrin and metalloprotease 17 (ADAM17), whose substrates, such as TNF-α and heparin-binding EGF (HB-EGF), have been implicated in the pathogenesis of chronic kidney disease. Here we demonstrate that deficiency of iRhom2 protects the lupus-prone Fcgr2b-/- mice from developing severe kidney damage without altering anti-double stranded (ds) DNA Ab production, by simultaneously blocking the HB-EGF/EGFR and the TNF-α signaling in the kidney tissues. Unbiased transcriptome profiling of kidneys and kidney macrophages revealed that TNF-α and HB-EGF/EGFR signaling pathways are highly upregulated in Fcgr2b-/- mice; alterations that were diminished in the absence of iRhom2. Pharmacological blockade of either TNF-α or EGFR signaling protected Fcgr2b-/- mice from severe renal damage. Finally, kidneys from LN patients showed increased iRhom2 and HB-EGF expression, with interstitial HB-EGF expression significantly associated with chronicity indices. Our data suggest that activation of iRhom2/ADAM17-dependent TNF-α and EGFR signaling plays a crucial role in mediating irreversible kidney damage in LN, thereby uncovering a novel target for selective and simultaneous dual inhibition of two major pathological pathways in the effector arm of the disease.
Project description:Adam17, a shedding protease, is strongly upregtulated during inflammation and cancer. Here we investigate the genome wide effects of Adam17 knock out on the transcriptome. Mouse tissue samples from n=3 wildtype colon, n=3 Adam17 knockout colon, n=3 wildtype skin and n=3 Adam17 knockout skin were used in the study.
Project description:This study investigates the role of ADAM17 (a disintegrin and metalloproteinase 17) in skin homeostasis. Here, we show that mice lacking ADAM17 in keratinocytes have a normal epidermal barrier and skin architecture at birth, but develop pronounced defects in epidermal barrier integrity soon after birth and chronic dermatitis as adults. The dysregulated expression of epidermal differentiation proteins becomes evident 2 days after birth, followed by transepidermal water loss and inflammatory immune cell infiltration. Our results identify a previously unappreciated critical role of the ADAM17/EGFR signaling axis in maintaining the homeostasis of the postnatal epidermal barrier. The genome-wide effects of ADAM17 deficiency were analyzed using Agilent Whole Mouse Genome microarrays. Conditional keratinocyte-specific ADAM17 knockout mice were generated by crossing Adam17flox/flox mice with keratin-14-Cre (Krt14-Cre) transgenic mice. Adam17flox/+Krt14-Cre mice were mated with Adam17flox/flox mice to generate pups of Adam17flox/flox Krt14-Cre positive (cKO) and Krt14-Cre negative (wild-type) control littermates. The genetic background was a mix of 129Sv and C57BL/6. As material, back skin tissue biopsies (postnatal day 10) from n = 2 wild-type skin and n = 2 ADAM17 epidermal KO skin (matched WT-cKO pairs from two different litters) were used in this study.
Project description:Adam17, a shedding protease, is strongly upregtulated during inflammation and cancer. Here we investigate the genome wide effects of Adam17 knock out on the transcriptome.
Project description:Membrane-tethered signalling proteins such as TNF������ and many EGF receptor ligands undergo shedding by the metalloproteinase ADAM17 to get released. The pseudoproteases iRhom1 and iRhom2 are important for the ER exit and activity of ADAM17. Yet, their structural requirements to promote ER exit remained unexplored. Utilising in silico and in vitro methods, we here map the conserved iRhom homology domain (IRHD) and provide insights into its structure and function. We identified a highly conserved motif within the IRHD, which is indispensable for the ER exit of iRhoms and termed it CERES (conserved ER exit sequence). Strikingly, single point mutations in CERES abrogate the ER exit without disrupting other iRhom functions. We confirmed the physiological significance of CERES by inactivating it in mice which abrogates ADAM17-mediated shedding ex vivo and in vivo. This demonstrates a crucial role of CERES in the ADAM17-dependent release of various growth factor and cytokine signals.