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11 result(s) for "Dekan, Sabine"
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PD-1 and PD-L1 expression on TILs in peritoneal metastases compared to ovarian tumor tissues and its associations with clinical outcome
The therapeutic potential of immune checkpoint inhibitors is currently being investigated in epithelial ovarian cancer (EOC), but immunological effects of the programmed cell death protein 1 (PD-1)/programmed cell death 1 ligand 1 (PD-L1) axis in EOC still remain poorly understood. The aim of this study was thus to compare infiltration rates of PD-1 and PD-L1 expressing tumor infiltrating leucocytes (TILs) in primary ovarian tumor tissue and metastatic intraperitoneal implants and to investigate its impact on overall survival (OS). Tumor specimens (ovarian tumor tissues and intraperitoneal metastases) of 111 patients were used to investigate the PD-1, PD-L1 and CD8 expression rates on TILs and PD-L1 expression rate of tumor cells. The percentages of CD8, PD-1, and PD-L1 expressing subpopulations of TILs differ in primary ovarian tumor tissues and metastatic intraperitoneal implants. High PD-1 among TILs in peritoneal metastases were associated with favorable OS. High PD-L1 expression in TILs was associated with poor OS. Combining both factors in peritoneal metastases revealed an unfavorable prognosis. Primary ovarian tumor tissue and intraperitoneal metastatic tissues in EOC might have different strategies to evade immune control. Those findings are of importance for the process of biomarker assessment to predict patients’ response to immunotherapy.
Epigenetic Alterations Affecting Transcription Factors and Signaling Pathways in Stromal Cells of Endometriosis
Endometriosis is characterized by growth of endometrial-like tissue outside the uterine cavity. Since its pathogenesis may involve epigenetic changes, we used Illumina 450K Methylation Beadchips to profile CpG methylation in endometriosis stromal cells compared to stromal cells from normal endometrium. We validated and extended the Beadchip data using bisulfite sequencing (bis-seq), and analyzed differential methylation (DM) at the CpG-level and by an element-level classification for groups of CpGs in chromatin domains. Genes found to have DM included examples encoding transporters (SLC22A23), signaling components (BDNF, DAPK1, ROR1, and WNT5A) and transcription factors (GATA family, HAND2, HOXA cluster, NR5A1, OSR2, TBX3). Intriguingly, among the TF genes with DM we also found JAZF1, a proto-oncogene affected by chromosomal translocations in endometrial stromal tumors. Using RNA-Seq we identified a subset of the DM genes showing differential expression (DE), with the likelihood of DE increasing with the extent of the DM and its location in enhancer elements. Supporting functional relevance, treatment of stromal cells with the hypomethylating drug 5aza-dC led to activation of DAPK1 and SLC22A23 and repression of HAND2, JAZF1, OSR2, and ROR1 mRNA expression. We found that global 5hmC is decreased in endometriotic versus normal epithelial but not stroma cells, and for JAZF1 and BDNF examined by oxidative bis-seq, found that when 5hmC is detected, patterns of 5hmC paralleled those of 5mC. Together with prior studies, these results define a consistent epigenetic signature in endometriosis stromal cells and nominate specific transcriptional and signaling pathways as therapeutic targets.
Markers of vitality in ovaries of transmen after long-term androgen treatment: a prospective cohort study
Background Gender-affirming hormone therapy has been hypothesized to reduce the patient’s reproductive potential in transmen, although the exact long-term effects on future fertility are unknown. Methods In this prospective cohort study we aimed to evaluate ovaries of 20 transmen by using hormone serum levels, histomorphological analysis and fluorescence activated cells sorting (FACS) analysis – in order to assess the amount of vital cells. Results The median total number of follicles per field of view was 39 (IQR 12–122). Of all follicles ( n =  1661), the vast majority was primordial ( n =  1505, 90.6%), followed by primary ( n =  76, 4.6%), abnormal ( n =  63, 3.8%) and secondary follicles ( n =  17, 1.0%). FACS analysis was available for 13 samples (65.0%) and the median frequency of vital cells was 87.5% (IQR, 77.7–95.4%). Both a higher age ( p =  0.032) and a lower BMI ( p =  0.003) were significantly associated with a higher frequency of vital cells. Conclusion The majority of ovarian cells after long-term androgen treatment were vital in FACS analysis and histomorphological evaluation revealed a normal cortical follicle distribution. These results are currently exploratory, but might be promising for issues on fertility preservation. Trial registration The study was approved by the ethics committee of the Medical University of Vienna (EK 2240/2016) and was retrospectively registered in the Current Controlled Trials Register (registration number NCT03649087 , date of registration: 28.08.2018).
Pregnancy-associated diamine oxidase originates from extravillous trophoblasts and is decreased in early-onset preeclampsia
Human extravillous trophoblast (EVT) invasion of the pregnant uterus constitutes a pivotal event for the establishment of the maternal-fetal interface. Compromised EVT function manifesting in inadequate arterial remodeling is associated with the severe pregnancy disorder early-onset preeclampsia (eoPE). Recent studies suggest that EVTs invade the entire uterine vasculature including arteries, veins and lymphatics in the first trimester of pregnancy. We therefore hypothesized that EVT-derived factors accumulate in the circulation of pregnant women early in gestation and may serve to predict eoPE. In contrast to published literature, we demonstrate that placenta-associated diamine oxidase (DAO) is not expressed by maternal decidual cells but solely by EVTs, especially when in close proximity to decidual vessels. Cultures of primary EVTs express and secret large amounts of bioactive DAO. ELISA measurements indicate a pregnancy-specific rise in maternal DAO plasma levels around gestational week (GW) 7 coinciding with vascular invasion of EVTs. Strikingly, DAO levels from eoPE cases were significantly lower (40%) compared to controls in the first trimester of pregnancy but revealed no difference at mid gestation. Furthermore, DAO-containing pregnancy plasma rapidly inactivates pathophysiologically relevant histamine levels. This study represents the first proof of concept suggesting EVT-specific signatures as diagnostic targets for the prediction of eoPE.
Role of mitochondrial DNA level in epidural-related maternal fever: a single-centre, observational, pilot study
Introduction Epidural analgesia has been associated with intrapartum maternal fever development. Epidural-related maternal fever (ERMF) is believed to be based on a non-infectious inflammatory reaction. Circulating cell-free mitochondrial deoxyribonucleic acid (mtDNA) is one of the possible triggers of sterile inflammatory processes; however, a connection has not been investigated so far. Therefore, this study aimed to investigate cell-free mtDNA alterations in women in labour with ERMF in comparison with non-febrile women. Material and methods A total of 60 women in labour were assessed for maternal temperature every 4 h and blood samples were obtained at the beginning and after delivery. Depending on the analgesia and the development of fever (axillary temperature ≥ 37.5 °C), the women were allocated either to the group of no epidural analgesia ( n  = 17), to epidural analgesia no fever ( n  = 34) or to ERMF ( n  = 9). Circulating cell-free mtDNA was analysed in the maternal plasma for the primary outcome whereas secondary outcomes include the evaluation of inflammatory cytokine release, as well as placental inflammatory signs. Results Of the women with epidural analgesia, 20% ( n  = 9) developed ERMF and demonstrated a decrease of circulating mtDNA levels during labour ( p  = 0.04), but a trend towards higher free nuclear DNA. Furthermore, women with maternal pyrexia showed a 1.5 fold increased level of Interleukin-6 during labour. A correlation was found between premature rupture of membranes and ERMF. Conclusions The pilot trial revealed an evident obstetric anaesthesia phenomenon of maternal fever due to epidural analgesia in 20% of women in labour, demonstrating counterregulated free mtDNA and nDNA. Further work is urgently required to understand the connections between the ERMF occurrence and circulating cell-free mtDNA as a potential source of sterile inflammation. Trial registration NCT0405223 on clinicaltrials.gov (registered on 25/07/2019).
RANK links thymic regulatory T cells to fetal loss and gestational diabetes in pregnancy
Successful pregnancies rely on adaptations within the mother 1 , including marked changes within the immune system 2 . It has long been known that the thymus, the central lymphoid organ, changes markedly during pregnancy 3 . However, the molecular basis and importance of this process remain largely obscure. Here we show that the osteoclast differentiation receptor RANK 4 , 5 couples female sex hormones to the rewiring of the thymus during pregnancy. Genetic deletion of Rank (also known as Tnfrsf11a ) in thymic epithelial cells results in impaired thymic involution and blunted expansion of natural regulatory T (T reg ) cells in pregnant female mice. Sex hormones, in particular progesterone, drive the development of thymic T reg cells through RANK in a manner that depends on AIRE + medullary thymic epithelial cells. The depletion of Rank in the mouse thymic epithelium results in reduced accumulation of natural T reg cells in the placenta, and an increase in the number of miscarriages. Thymic deletion of Rank also results in impaired accumulation of T reg cells in visceral adipose tissue, and is associated with enlarged adipocyte size, tissue inflammation, enhanced maternal glucose intolerance, fetal macrosomia, and a long-lasting transgenerational alteration in glucose homeostasis, which are all key hallmarks of gestational diabetes. Transplantation of T reg cells rescued fetal loss, maternal glucose intolerance and fetal macrosomia. In human pregnancies, we found that gestational diabetes also correlates with a reduced number of T reg cells in the placenta. Our findings show that RANK promotes the hormone-mediated development of thymic T reg cells during pregnancy, and expand the functional role of maternal T reg cells to the development of gestational diabetes and the transgenerational metabolic rewiring of glucose homeostasis. RANK promotes the hormone-mediated development of thymic regulatory T cells during pregnancy; loss of RANK is associated with impaired maturation of maternal regulatory T cells, leading to fetal loss and the development of gestational diabetes.
Absence of PD-L1 on tumor cells is associated with reduced MHC I expression and PD-L1 expression increases in recurrent serous ovarian cancer
Immune-evasion and immune checkpoints are promising new therapeutic targets for several cancer entities. In ovarian cancer, the clinical role of programmed cell death receptor ligand 1 (PD-L1) expression as mechanism to escape immune recognition has not been clarified yet. We analyzed PD-L1 expression of primary ovarian and peritoneal tumor tissues together with several other parameters (whole transcriptomes of isolated tumor cells, local and systemic immune cells, systemic cytokines and metabolites) and compared PD-L1 expression between primary tumor and tumor recurrences. All expressed major histocompatibility complex (MHC) I genes were negatively correlated to PD-L1 abundances on tumor tissues, indicating two mutually exclusive immune-evasion mechanisms in ovarian cancer: either down-regulation of T-cell mediated immunity by PD-L1 expression or silencing of self-antigen presentation by down-regulation of the MHC I complex. In our cohort and in most of published evidences in ovarian cancer, low PD-L1 expression is associated with unfavorable outcome. Differences in immune cell populations, cytokines, and metabolites strengthen this picture and suggest the existence of concurrent pathways for progression of this disease. Furthermore, recurrences showed significantly increased PD-L1 expression compared to the primary tumors, supporting trials of checkpoint inhibition in the recurrent setting.
NECTIN4 (PVRL4) as Putative Therapeutic Target for a Specific Subtype of High Grade Serous Ovarian Cancer—An Integrative Multi-Omics Approach
In high grade serous ovarian cancer patients with peritoneal involvement and unfavorable outcome would benefit from targeted therapies. The aim of this study was to find a druggable target against peritoneal metastasis. We constructed a planar—scale free small world—co-association gene expression network and searched for clusters with hub-genes associated to peritoneal spread. Protein expression and impact was validated via immunohistochemistry and correlations of deregulated pathways with comprehensive omics data were used for biological interpretation. A cluster up-regulated in miliary tumors with NECTIN4 as hub-gene was identified and impact on survival validated. High Nectin 4 protein expression was associated with unfavorable survival and (i) reduced expression of HLA genes (mainly MHC I); (ii) with reduced expression of genes from chromosome 22q11/12; (iii) higher BCAM in ascites and in a high-scoring expression cluster; (iv) higher Kallikrein gene and protein expressions; and (v) substantial immunologic differences; locally and systemically; e.g., reduced CD14 positive cells and reduction of different natural killer cell populations. Each three cell lines with high (miliary) or low NECTIN4 expression (non-miliary) were identified. An anti-Nectin 4 antibody with a linked antineoplastic drug–already under clinical investigation–could be a candidate for a targeted therapy in patients with extensive peritoneal involvement.
A Global Gene Body Methylation Measure Correlates Independently with Overall Survival in Solid Cancer Types
Epigenetics, CpG methylation of CpG islands (CGI) and gene bodies (GBs), plays an important role in gene regulation and cancer biology, the former established as a transcription regulator. Genome wide CpG methylation, summarized over GBs and CGIs, was analyzed for impact on overall survival (OS) in cancer. The averaged GB and CGI methylation status of each gene was categorized into methylated and unmethylated (defined) or undefined. Differentially methylated GBs and genes associated with their GB methylation status were compared to the corresponding CGI methylation states and biologically annotated. No relevant correlations of GB and CGI methylation or GB methylation and gene expression were observed. Summarized GB methylation showed impact on OS in ovarian, breast, colorectal, and pancreatic cancer, and glioblastoma, but not in lung cancer. In ovarian, breast, and colorectal cancer more defined GBs correlated with unfavorable OS, in pancreatic cancer with favorable OS and in glioblastoma more methylated GBs correlated with unfavorable OS. The GB methylation of genes were similar over different samples and even over cancer types; nevertheless, the clustering of different cancers was possible. Gene expression differences associated with summarized GB methylation were cancer specific. A genome-wide dysregulation of gene-body methylation showed impact on the outcome in different cancers.