130,482 research outputs found
Endoplasmic reticulum aminopeptidase 1 function and its pathogenic role in regulating innate and adaptive immunity in cancer and major histocompatibility complex class I-associated autoimmune diseases
Influence of the Tumor Microenvironment on NK Cell Function in Solid Tumors
Natural killer (NK) cells are a population of innate lymphoid cells playing a pivotal role in host immune responses against infection and tumor growth. These cells have a powerful cytotoxic activity orchestrated by an intricate network of inhibitory and activating signals. The importance of NK cells in controlling tumor growth and in mediating a robust anti-metastatic effect has been demonstrated in different experimental mouse cancer models. Consistently, high density of tumor-infiltrating NK cells has been linked with a good prognosis in multiple human solid tumors. However, there are also tumors that appear to be refractory to NK cell-mediated killing for the presence of an immunosuppressive microenvironment affecting NK cell function. Immunotherapeutic strategies aimed at restoring and increasing the cytotoxic activity of NK cells in solid tumors, including the adoptive transfer of NK and CAR-NK cells, are currently employed in preclinical and clinical studies. In this review, we outline recent advances supporting the direct role of NK cells in controlling expansion of solid tumors and their prognostic value in human cancers. We summarize the mechanisms adopted by cancer cells and the tumor microenvironment to affect NK cell function, and finally we evaluate current strategies to augment the antitumor function of NK cells for the treatment of solid tumors
T and NK cells: Two sides of tumor immunoevasion
Natural Killer (NK) cells are known to reject several experimental murine tumors, but their antineoplastic activity in humans is not generally agreed upon, as exemplified by an interesting correspondence recently appeared in Cancer Research. In the present commentary, we join the discussion and bring to the attention of the readers of the Journal of Translational Medicine a set of recent, related reports. These studies demonstrate that effectors of the adaptive and innate immunity need to actively cooperate in order to reject tumors and, conversely, tumors protect themselves by dampening both T and NK cell responses. The recently reported ability of indoleamine 2,3-dioxygenase (IDO) and prostaglandin E2 (PGE2) expressed by melanoma cells to down-regulate activating NK receptors is yet another piece of evidence supporting combined and highly effective T/NK cell disabling. Major Histocompatibility Complex class I (MHC-I) molecules, including Human Leukocyte Antigen E (HLA-E), represent another class of shared activating/inhibitory ligands. Ongoing clinical trials with small molecules interfering with IDO and PGE2 may be exploiting an immune bonus to control cancer. Conversely, failure to simultaneously engage effectors of both the innate and the adaptive immunity may contribute to explain the limited clinical efficacy of T cell-only vaccination trials. Shared (T/NK cells) natural immunosuppressants and activating/inhibitory ligands expressed by tumor cells may provide mechanistic insight into impaired gathering and function of immune effectors at the tumor site. © 2013 Fruci et al.; licensee BioMed Central Ltd
D. Di Bartolomeo, Nelle vesti di Clio. L’uso politico della storia nella Rivoluzione francese (1787-1799), Roma, Viella, 2014
Recensione del volume: Nelle vesti di Clio : l'uso politico della storia nella Rivoluzione francese (1787-1799) / Daniele Di Bartolomeo. - Roma : Viella, 2014. - (La storia. Temi ; 41)
ERAP1 as an emerging therapeutic target for medulloblastoma
Endoplasmic reticulum aminopeptidase 1 (ERAP1) is a multifunctional enzyme that shapes the peptide repertoire presented by major histocompatibility complex class I (MHC-I) molecules, thereby affecting tumor immunogenicity. ERAP1 is altered in many tumors, including medulloblastoma (MB). We review the role of ERAP1 in MB development and the possibility of targeting this enzyme for MB treatment
Role of genetic variations on MHC class I antigen-processing genes in human cancer and viral-mediated diseases
Cytotoxic T lymphocytes constantly monitor peptide-MHC class I complexes on the cell surface to eliminate transformed and virally infected cells expressing peptides derived from abnormal proteins. The generation of antigenic peptides and their loading on MHC class I molecules is a multistep process involving different molecules that constitute the so-called antigen processing and presentation machinery (APM). To avoid immune-mediated elimination, human tumors and pathogens have adopted different strategies including loss of MHC class I expression and dysregulation of APM genes and proteins. Here, we summarize recent knowledge on genetic variations in APM genes and their association with cancer development and viral-mediated diseases
Regulation of {ERAP}1 and {ERAP}2 genes and their disfunction in human cancer
The endoplasmic reticulum (ER) aminopeptidases ERAP1 and ERAP2 are two multifunctional enzymes playing an important role in the biological processes requiring trimming of substrates, including the generation of major histocompatibility complex (MHC) class I binding peptides. In the absence of ERAP enzymes, the cells exhibit a different pool of peptides on their surface which can promote both NK and CD8+ T cell-mediated immune responses. The expression of ERAP1 and ERAP2 is frequently altered in tumors, as compared to their normal counterparts, but how this affects tumor growth and anti-tumor immune responses has been little investigated. This review will provide an overview of current knowledge on transcriptional and post-transcriptional regulations of ERAP enzymes, and will discuss the contribution of recent studies to our understanding of ERAP1 and ERAP2 role in cancer immunity
The putative role of endoplasmic reticulum aminopeptidases in autoimmunity: Insights from genomic-wide association studies.
Autoimmune diseases represent a heterogeneous group of conditions whose incidence is increasing worldwide. This has stimulated studies on their etiopathogenesis, derived from a complex interaction between genetic and environmental factors, aimed at finally improving prevention and treatment of these diseases. In the autoimmune process, immune responses are generated against self antigens presented by Major Histocompatibility Complex (MHC) class I on the cell surface. These peptide/MHC class I complexes are generated and assembled through MHC class I antigen processing and presentation machinery. In the endoplasmic reticulum (ER), aminopeptidases ERAP1 and ERAP2 display distinct trimming activity before antigenic peptides are loaded onto MHC class I molecules. The advent of new tools such as genome-wide association studies (GWAS) has provided evidence for new susceptibility loci and candidate genes playing a role in the autoimmune process for the recognized immune function of their transcripts. Genetic linkage has been discovered with MHC antigens and various autoimmune conditions. Recent GWAS showed the importance of ERAP1 and ERAP2 in several autoimmune diseases, including ankylosing spondylitis, insulin-dependent diabetes mellitus, psoriasis, multiple sclerosis, Crohn's disease. In this review, we first provide a general overview of ERAP1 and ERAP2 genes, their biological functions and their relevancy in autoimmunity. We then discuss the importance of GWAS and the case-control studies that confirm the relevancy of ERAP single-nucleotide polymorphism associations and their linkage with particular MHC class I haplotypes, supporting a putative functional role in the autoimmune process
Impact of natural occurring erap1 single nucleotide polymorphisms within mirna-binding sites on hcmv infection
human cytomegalovirus (HCMV) is a beta-herpesvirus that causes serious problems in people with a compromised immune system, whereas it coexists asymptomatically within the host with a healthy immune system. Like other viruses, HCMV has adopted multiples strategies to manipulate the host's immune responses. among them, expression of viral microRNAs (miRNAs) is one of the most intriguing. HCMV miR-UL112-5p and miR-US4-1 have been found to contribute to immune evasion by targeting the endoplasmic reticulum aminopeptidase 1 (ERAP1), a highly polymorphic key component of antigen processing. the current incomplete picture on the interplay between viral miRNAs and host immunity implies the need to better characterize the host genetic determinants. naturally occurring single nucleotide polymorphisms (SNPs) within the miRNA binding sites of target genes may affect miRNA-target interactions. In this review, we focus on the relevance of 3 ' untranslated region (3 ' UTR)ERAP1SNPs within miRNA binding sites in modulating miRNA-mRNA interactions and the possible consequent individual susceptibility to HCMV infection. moreover, we performed an in silico analysis using different bioinformatic algorithms to predictERAP1variants with a putative powerful biological function. this evidence provides a basis to deepen the knowledge on how 3 ' UTRERAP1variants may alter the mechanism of action of HCMV miRNAs, in order to develop targeted antiviral therapies
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