Structure and function of ETAA16: a novel cell surface antigen in Ewing's tumours

The Genetic Background of Endometriosis: Can ESR2 and CYP19A1 Genes Be a Potential Risk Factor for Its Development?

Endometriosis is defined as the presence of endometrial foci, localized beyond their primary site, i.e., the uterine cavity. The etiology of this disease is rather complex. Its development is supported by hormonal, immunological, and environmental factors. During recent years, particular attention has been focused on the genetic mechanisms that may be of particular significance for the increased incidence rates of endometriosis. According to most recent studies, ESR2 and CYP19A1 genes may account for the potential risk factors of infertility associated with endometriosis. The paper presents a thorough review of the latest reports and data concerning the genetic background of the risk for endometriosis development.

Systematic review of genome-wide association studies on susceptibility to endometriosis

Endometriosis is a complex and heterogeneous disease in which extrinsic and intrinsic factors, such as genetics, provide to the disease development. Genome-wide association (GWA) studies may be essential to recognize genetic variants associated with the endometriosis risk. However, in the current literature there are some conflicting results between these studies. The aim of the present study was to undertake a systematic review about endometriosis GWA studies, to describe the disease-associated genes and single nucleotide polymorphisms (SNPs) to try to understand the endometriosis etiopathogenesis, besides to discuss possible bias of conflicting results among these studies. This study is a systematic review of GWA studies in endometriosis published until December 31^th, 2019 by PubMed database, considering the following descriptors: endometriosis and ("polymorphism" or "SNP" or "genetic polymorphism" or "variants" or "locus") and ("GWA" or "Genome-wide" or "Genome wide" or "Genetic association study"). The included studies were analyzed with methodological rigor (STROBE and PRISMA) to enable better quality of case-control and meta-analysis studies, respectively. Of the 88 articles found, only 15 were eligible. All articles had appropriate quality evaluated by STROBE and PRISMA checklists (77% and 81%, respectively). Overall, 35,022 endometriosis cases and 181,760 controls were analyzed. The number of participants in each study was quite different (171 to 17,045 for the cases and 308 to 150,021 for the controls), with a predominance of European ethnicity. Most endometriosis cases (86%) were diagnosed by surgery, while selection of the control group was different among studies. About 47% performed only one stage (discovery stage) and 53% performed both the discovery and replication analyses. Eleven genes/SNPs were associated with endometriosis risk in more than one article (chromosome 1, 2, 6, 7, 9 and 12; WNT4, GREB1, FN1, IL1A, ETAA1, RND3, ID4, NFE2L3, CDKN2B-AS1 and VEZT). SNPs were localized in intergenic and intronic regions, their risk allele frequencies varied among the studies and their results were conflicting. In summary, WNT4 rs7521902, GREB1 rs13394619, FN1 rs1250248, IL1A rs6542095 and VEZT rs10859871 variants are highlighted due to high frequency and pathways and function that each gene influences in the development of endometriosis. However, the replication and validation of these variants in different populations are necessary for a better understanding of the endometriosis etiopathogenesis, in order to optimize the diagnosis and improve the efficiency of clinical treatment of the disease.

Bone sarcomas in the immunotherapy era

Bone sarcomas are primary bone tumours found mainly in children and adolescents, as osteosarcoma and Ewing's sarcoma, and in adults in their 40s as chondrosarcoma. The last four decades the development of therapeutic approaches was based on drug combinations have shown no real improvement in overall survival. Recently oncoimmunology has allowed a better understand of the crucial role played by the immune system in the oncologic process. This led to clinical trials with the aim of reprogramming the immune system to facilitate cancer cell recognition. Immune infiltrates of bone sarcomas have been characterized and their molecular profiling identified as immune therapeutic targets. Unfortunately, the clinical responses in trials remain anecdotal but highlight the necessity to improve the characterization of tumour micro-environment to unlock the immunotherapeutic response, especially in their paediatric forms. Bone sarcomas have entered the immunotherapy era and here we overview the recent developments in immunotherapies in these sarcomas. LINKED ARTICLES: This article is part of a themed issue on The molecular pharmacology of bone and cancer-related bone diseases. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.9/issuetoc.

Systems-guided forward genetic screen reveals a critical role of the replication stress response protein ETAA1 in T cell clonal expansion

T-cell immunity requires extremely rapid clonal proliferation of rare, antigen-specific T lymphocytes to form effector cells. Here we identify a critical role for ETAA1 in this process by surveying random germ line mutations in mice using exome sequencing and bioinformatic annotation to prioritize mutations in genes of unknown function with potential effects on the immune system, followed by breeding to homozygosity and testing for immune system phenotypes. Effector CD8⁺ and CD4⁺ T-cell formation following immunization, lymphocytic choriomeningitis virus (LCMV) infection, or herpes simplex virus 1 (HSV1) infection was profoundly decreased despite normal immune cell development in adult mice homozygous for two different Etaa1 mutations: an exon 2 skipping allele that deletes Gly78-Leu119, and a Cys166Stop truncating allele that eliminates most of the 877-aa protein. ETAA1 deficiency decreased clonal expansion cell autonomously within the responding T cells, causing no decrease in their division rate but increasing TP53-induced mRNAs and phosphorylation of H2AX, a marker of DNA replication stress induced by the ATM and ATR kinases. Homozygous ETAA1-deficient adult mice were otherwise normal, healthy, and fertile, although slightly smaller, and homozygotes were born at lower frequency than expected, consistent with partial lethality after embryonic day 12. Taken together with recently reported evidence in human cancer cell lines that ETAA1 activates ATR kinase through an exon 2-encoded domain, these findings reveal a surprisingly specific requirement for this ATR activator in adult mice restricted to rapidly dividing effector T cells. This specific requirement may provide new ways to suppress pathological T-cell responses in transplantation or autoimmunity.

RPA-Binding Protein ETAA1 Is an ATR Activator Involved in DNA Replication Stress Response

ETAA1 (Ewing tumor-associated antigen 1), also known as ETAA16, was identified as a tumor-specific antigen in the Ewing family of tumors. However, the biological function of this protein remains unknown. Here, we report the identification of ETAA1 as a DNA replication stress response protein. ETAA1 specifically interacts with RPA (Replication protein A) via two conserved RPA-binding domains and is therefore recruited to stalled replication forks. Interestingly, further analysis of ETAA1 function revealed that ETAA1 participates in the activation of ATR signaling pathway via a conserved ATR-activating domain (AAD) located near its N terminus. Importantly, we demonstrate that both RPA binding and ATR activation are required for ETAA1 function at stalled replication forks to maintain genome stability. Therefore, our data suggest that ETAA1 is a new ATR activator involved in replication checkpoint control.

Activation of the ATR kinase by the RPA-binding protein ETAA1

Activation of the ATR kinase following perturbations to DNA replication relies on a complex mechanism involving ATR recruitment to RPA-coated single-stranded DNA via its binding partner ATRIP and stimulation of ATR kinase activity by TopBP1. Here, we discovered an independent ATR activation pathway in vertebrates, mediated by the uncharacterized protein ETAA1 (Ewing's tumour-associated antigen 1). Human ETAA1 accumulates at DNA damage sites via dual RPA-binding motifs and promotes replication fork progression and integrity, ATR signalling and cell survival after genotoxic insults. Mechanistically, this requires a conserved domain in ETAA1 that potently and directly stimulates ATR kinase activity independently of TopBP1. Simultaneous loss of ETAA1 and TopBP1 gives rise to synthetic lethality characterized by massive genome instability and abrogation of ATR-dependent signalling. Our findings demonstrate that parallel TopBP1- and ETAA1-mediated pathways underlie ATR activation and that their combined action is essential for coping with replication stress.

ETAA1 acts at stalled replication forks to maintain genome integrity

The ATR checkpoint kinase coordinates cellular responses to DNA replication stress. Budding yeast contain three activators of Mec1 (the ATR orthologue); however, only TOPBP1 is known to activate ATR in vertebrates. We identified ETAA1 as a replication stress response protein in two proteomic screens. ETAA1-deficient cells accumulate double-strand breaks, sister chromatid exchanges, and other hallmarks of genome instability. They are also hypersensitive to replication stress and have increased frequencies of replication fork collapse. ETAA1 contains two RPA-interaction motifs that localize ETAA1 to stalled replication forks. It also interacts with several DNA damage response proteins including the BLM/TOP3α/RMI1/RMI2 and ATR/ATRIP complexes. It binds ATR/ATRIP directly using a motif with sequence similarity to the TOPBP1 ATR-activation domain; and like TOPBP1, ETAA1 acts as a direct ATR activator. ETAA1 functions in parallel to the TOPBP1/RAD9/HUS1/RAD1 pathway to regulate ATR and maintain genome stability. Thus, vertebrate cells contain at least two ATR-activating proteins.

Beyond Endometriosis Genome-Wide Association Study: From Genomics to Phenomics to the Patient

Endometriosis is a heritable, complex chronic inflammatory disease, for which much of the causal pathogenic mechanism remains unknown. Genome-wide association studies (GWAS) to date have identified 12 single nucleotide polymorphisms at 10 independent genetic loci associated with endometriosis. Most of these were more strongly associated with revised American Fertility Society stage III/IV, rather than stage I/II. The loci are almost all located in intergenic regions that are known to play a role in the regulation of expression of target genes yet to be identified. To identify the target genes and pathways perturbed by the implicated variants, studies are required involving functional genomic annotation of the surrounding chromosomal regions, in terms of transcription factor binding, epigenetic modification (e.g., DNA methylation and histone modification) sites, as well as their correlation with RNA transcription. These studies need to be conducted in tissue types relevant to endometriosis-in particular, endometrium. In addition, to allow biologically and clinically relevant interpretation of molecular profiling data, they need to be combined and correlated with detailed, systematically collected phenotypic information (surgical and clinical). The WERF Endometriosis Phenome and Biobanking Harmonisation Project is a global standardization initiative that has produced consensus data and sample collection protocols for endometriosis research. These now pave the way for collaborative studies integrating phenomic with genomic data, to identify informative subtypes of endometriosis that will enhance understanding of the pathogenic mechanisms of the disease and discovery of novel, targeted treatments.

Pancreatic Cancer Genetics

Although relatively rare, pancreatic tumors are highly lethal [1]. In the United States, an estimated 48,960 individuals will be diagnosed with pancreatic cancer and 40,560 will die from this disease in 2015 [1]. Globally, 337,872 new pancreatic cancer cases and 330,391 deaths were estimated in 2012 [2]. In contrast to most other cancers, mortality rates for pancreatic cancer are not improving; in the US, it is predicted to become the second leading cause of cancer related deaths by 2030 [3, 4]. The vast majority of tumors arise in the exocrine pancreas, with pancreatic ductal adenocarcinoma (PDAC) accounting for approximately 95% of tumors. Tumors arising in the endocrine pancreas (pancreatic neuroendocrine tumors) represent less than 5% of all pancreatic tumors [5]. Smoking, type 2 diabetes mellitus (T2D), obesity and pancreatitis are the most consistent epidemiological risk factors for pancreatic cancer [5]. Family history is also a risk factor for developing pancreatic cancer with odds ratios (OR) ranging from 1.7-2.3 for first-degree relatives in most studies, indicating that shared genetic factors may play a role in the etiology of this disease [6-9]. This review summarizes the current knowledge of germline pancreatic cancer risk variants with a special emphasis on common susceptibility alleles identified through Genome Wide Association Studies (GWAS).

Genetics of endometriosis

Endometriosis is a heritable complex disorder that is influenced by multiple genetic and environmental factors. Identification of these genetic factors will aid a better understanding of the underlying biology of the disease. In this article, we describe different methods of studying genetic variation of endometriosis, summarize results from genetic studies performed to date and provide recommendations for future studies to uncover additional factors contributing to the heritable component of endometriosis.

Common variation at 2p13.3, 3q29, 7p13 and 17q25.1 associated with susceptibility to pancreatic cancer

Pancreatic cancer is the fourth leading cause of cancer death in the developed world. Both inherited high-penetrance mutations in BRCA2 (ref. 2), ATM, PALB2 (ref. 4), BRCA1 (ref. 5), STK11 (ref. 6), CDKN2A and mismatch-repair genes and low-penetrance loci are associated with increased risk. To identify new risk loci, we performed a genome-wide association study on 9,925 pancreatic cancer cases and 11,569 controls, including 4,164 newly genotyped cases and 3,792 controls in 9 studies from North America, Central Europe and Australia. We identified three newly associated regions: 17q25.1 (LINC00673, rs11655237, odds ratio (OR) = 1.26, 95% confidence interval (CI) = 1.19-1.34, P = 1.42 × 10(-14)), 7p13 (SUGCT, rs17688601, OR = 0.88, 95% CI = 0.84-0.92, P = 1.41 × 10(-8)) and 3q29 (TP63, rs9854771, OR = 0.89, 95% CI = 0.85-0.93, P = 2.35 × 10(-8)). We detected significant association at 2p13.3 (ETAA1, rs1486134, OR = 1.14, 95% CI = 1.09-1.19, P = 3.36 × 10(-9)), a region with previous suggestive evidence in Han Chinese. We replicated previously reported associations at 9q34.2 (ABO), 13q22.1 (KLF5), 5p15.33 (TERT and CLPTM1), 13q12.2 (PDX1), 1q32.1 (NR5A2), 7q32.3 (LINC-PINT), 16q23.1 (BCAR1) and 22q12.1 (ZNRF3). Our study identifies new loci associated with pancreatic cancer risk.

Genetic variants underlying risk of endometriosis: insights from meta-analysis of eight genome-wide association and replication datasets

BACKGROUND

Endometriosis is a heritable common gynaecological condition influenced by multiple genetic and environmental factors. Genome-wide association studies (GWASs) have proved successful in identifying common genetic variants of moderate effects for various complex diseases. To date, eight GWAS and replication studies from multiple populations have been published on endometriosis. In this review, we investigate the consistency and heterogeneity of the results across all the studies and their implications for an improved understanding of the aetiology of the condition.

METHODS

Meta-analyses were conducted on four GWASs and four replication studies including a total of 11 506 cases and 32 678 controls, and on the subset of studies that investigated associations for revised American Fertility Society (rAFS) Stage III/IV including 2859 cases. The datasets included 9039 cases and 27 343 controls of European (Australia, Belgium, Italy, UK, USA) and 2467 cases and 5335 controls of Japanese ancestry. Fixed and Han and Elkin random-effects models, and heterogeneity statistics (Cochran's Q test), were used to investigate the evidence of the nine reported genome-wide significant loci across datasets and populations.

RESULTS

Meta-analysis showed that seven out of nine loci had consistent directions of effect across studies and populations, and six out of nine remained genome-wide significant (P < 5 × 10⁻⁸), including rs12700667 on 7p15.2 (P = 1.6 × 10⁻⁹), rs7521902 near WNT4 (P = 1.8 × 10⁻¹⁵), rs10859871 near VEZT (P = 4.7 × 10⁻¹⁵), rs1537377 near CDKN2B-AS1 (P = 1.5 × 10⁻⁸), rs7739264 near ID4 (P = 6.2 × 10⁻¹⁰) and rs13394619 in GREB1 (P = 4.5 × 10⁻⁸). In addition to the six loci, two showed borderline genome-wide significant associations with Stage III/IV endometriosis, including rs1250248 in FN1 (P = 8 × 10⁻⁸) and rs4141819 on 2p14 (P = 9.2 × 10⁻⁸). Two independent inter-genic loci, rs4141819 and rs6734792 on chromosome 2, showed significant evidence of heterogeneity across datasets (P < 0.005). Eight of the nine loci had stronger effect sizes among Stage III/IV cases, implying that they are likely to be implicated in the development of moderate to severe, or ovarian, disease. While three out of nine loci were inter-genic, the remaining were in or near genes with known functions of biological relevance to endometriosis, varying from roles in developmental pathways to cellular growth/carcinogenesis.

CONCLUSIONS

Our meta-analysis shows remarkable consistency in endometriosis GWAS results across studies, with little evidence of population-based heterogeneity. They also show that the phenotypic classifications used in GWAS to date have been limited. Stronger associations with Stage III/IV disease observed for most loci emphasize the importance for future studies to include detailed sub-phenotype information. Functional studies in relevant tissues are needed to understand the effect of the variants on downstream biological pathways.

Presphenoidal synchondrosis fusion in DBA/2J mice

Cranial base growth plates are important centers of longitudinal growth in the skull and are responsible for the proper anterior placement of the face and the stimulation of normal cranial vault development. We report that the presphenoidal synchondrosis (PSS), a midline growth plate of the cranial base, closes in the DBA/2J mouse strain but not in other common inbred strains. We investigated the genetics of PSS closure in DBA/2J mice by evaluating F1, F1 backcross, and/or F1 intercross offspring from matings with C57BL/6J and DBA/1J mice, whose PSS remain open. We observed that PSS closure is genetically determined, but not inherited as a simple Mendelian trait. Employing a genome-wide SNP array, we identified a region on chromosome 11 in the C57BL/6J strain that affected the frequency of PSS closure in F1 backcross and F1 intercross offspring. The equivalent region in the DBA/1J strain did not affect PSS closure in F1 intercross offspring. We conclude that PSS closure in the DBA/2J strain is complex and modified by different loci when outcrossed with C57BL/6J and DBA/1J mice.