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Excessive endometrial angiogenesis is proposed as an important mechanism in the pathogenesis of endometriosis. Evidence is reviewed for the hypothesis that the endometrium of women with endometriosis has an increased capacity to proliferate, implant and grow in the peritoneal cavity. Data is summarized indicating that the endometrium of patients with endometriosis shows enhanced endothelial cell proliferation. Results are also reviewed indicating that the cell adhesion molecule integrin αvβ3 is expressed in more blood vessels in the endometrium of women with endometriosis when compared with normal women. Taken together, these results provide evidence for increased endometrial angiogenesis in women with endometriosis when compared with normal subjects. Endometriosis is one of the family of angiogenic diseases. Other angiogenic diseases include solid tumours, rheumatoid arthritis, psoriasis and diabetic retinopathy. Excessive endometrial angiogenesis suggests novel new medical treatments for endometriosis aimed at the inhibition of angiogenesis. [ABSTRACT FROM PUBLISHER]

Background: Point mutations in histone variant H3.3 (H3.3K27M, H3.3G34R) and the H3.3-specific ATRX/DAXX chaperone complex are frequent events in pediatric gliomas. These H3.3 point mutations affect many chromatin modifications but the exact oncogenic mechanisms are currently unclear. Histone H3.3 is known to localize to nuclear compartments known as promyelocytic leukemia (PML) nuclear bodies, which are frequently mutated and confirmed as oncogenic drivers in acute promyelocytic leukemia., Results: We find that the pediatric glioma-associated H3.3 point mutations disrupt the formation of PML nuclear bodies and this prevents differentiation down glial lineages. Similar to leukemias driven by PML mutations, H3.3-mutated glioma cells are sensitive to drugs that target PML bodies. We also find that point mutations in IDH1/2-which are common events in adult gliomas and myeloid leukemias-also disrupt the formation of PML bodies., Conclusions: We identify PML as a contributor to oncogenesis in a subset of gliomas and show that targeting PML bodies is effective in treating these H3.3-mutated pediatric gliomas., (© 2023. The Author(s).)

Tumour progression relies on interactions with untransformed cells in the tumour microenvironment (TME), including cancer-associated fibroblasts (CAFs), which promote blood supply, tumour progression, and immune evasion. Eph receptor tyrosine kinases are cell guidance receptors that are most active during development but re-emerge in cancer and are recognised drug targets. EphA3 is overexpressed in a wide range of tumour types, and we previously found expression particularly in stromal and vascular tissues of the TME. To investigate its role in the TME, we generated transgenic mice with inducible shRNA-mediated knockdown of EphA3 expression. EphA3 knockdown was confirmed in aortic mesenchymal stem cells (MSCs), which displayed reduced angiogenic capacity. In mice with syngeneic lung tumours, EphA3 knockdown reduced vasculature and CAF/MSC-like cells in tumours, and inhibited tumour growth, which was confirmed also in a melanoma model. Single cell RNA sequencing analysis of multiple human tumour types confirmed EphA3 expression in CAFs, including in breast cancer, where EphA3 was particularly prominent in perivascular- and myofibroblast-like CAFs. Our results thus indicate expression of the cell guidance receptor EphA3 in distinct CAF subpopulations is important in supporting tumour angiogenesis and tumour growth, highlighting its potential as a therapeutic target.

Objectives: To examine the severity of coronary artery disease (CAD) in people from rural or remote Western Australia referred for invasive coronary angiography (ICA) in Perth and their subsequent management; to estimate the cost savings were computed tomography coronary angiography (CTCA) offered in rural centres as a first line investigation for people with suspected CAD., Design: Retrospective cohort study., Setting, Participants: Adults with stable symptoms in rural and remote WA referred to Perth public tertiary hospitals for ICA evaluation during the 2019 calendar year., Main Outcome Measures: Severity and management of CAD (medical management or revascularisation); health care costs by care model (standard care or a proposed alternative model with local CTCA assessment)., Results: The mean age of the 1017 people from rural and remote WA who underwent ICA in Perth was 62 years (standard deviation, 13 years); 680 were men (66.9%), 245 were Indigenous people (24.1%). Indications for referral were non-ST elevation myocardial infarction (438, 43.1%), chest pain with normal troponin level (394, 38.7%), and other (185, 18.2%). After ICA assessment, 619 people were medically managed (60.9%) and 398 underwent revascularisation (39.1%). None of the 365 patients (35.9%) without obstructed coronaries (< 50% stenosis) underwent revascularisation; nine patients with moderate CAD (50-69% stenosis; 7%) and 389 with severe CAD (≥ 70% stenosis or occluded vessel; 75.5%) underwent revascularisation. Were CTCA used locally to determine the need for referral, 527 referrals could have been averted (53%), the ICA:revascularisation ratio would have improved from 2.6 to 1.6, and 1757 metropolitan hospital bed-days (43% reduction) and $7.3 million in health care costs (36% reduction) would have been saved., Conclusion: Many rural and remote Western Australians transferred for ICA in Perth have non-obstructive CAD and are medically managed. Providing CTCA as a first line investigation in rural centres could avert half of these transfers and be a cost-effective strategy for risk stratification of people with suspected CAD., (© 2023 The Authors. Medical Journal of Australia published by John Wiley & Sons Australia, Ltd on behalf of AMPCo Pty Ltd.)

ADAM10 is a transmembrane metalloprotease that sheds a variety of cell surface proteins, including receptors and ligands that regulate a range of developmental processes which re-emerge during tumour development. While ADAM10 is ubiquitously expressed, its activity is normally tightly regulated, but becomes deregulated in tumours. We previously reported the generation of a monoclonal antibody, 8C7, which preferentially recognises an active form of ADAM10 in human and mouse tumours. We now report our investigation of the mechanism of this specificity, and the preferential targeting of 8C7 to human tumour cell xenografts in mice. We also report the development of novel 8C7 antibody-drug conjugates that preferentially kill cells displaying the 8C7 epitope, and that can inhibit tumour growth in mice. This study provides the first demonstration that antibody-drug conjugates targeting an active conformer of ADAM10, a widely expressed transmembrane metalloprotease, enable tumour-selective targeting and inhibition.

Histone H3.3 is an H3 variant which differs from the canonical H3.1/2 at four residues, including a serine residue at position 31 which is evolutionarily conserved. The H3.3 S31 residue is phosphorylated (H3.3 S31Ph) at heterochromatin regions including telomeres and pericentric repeats. However, the role of H3.3 S31Ph in these regions remains unknown. In this study, we find that H3.3 S31Ph regulates heterochromatin accessibility at telomeres during replication through regulation of H3K9/K36 histone demethylase KDM4B. In mouse embryonic stem (ES) cells, substitution of S31 with an alanine residue (H3.3 A31 -phosphorylation null mutant) results in increased KDM4B activity that removes H3K9me3 from telomeres. In contrast, substitution with a glutamic acid (H3.3 E31, mimics S31 phosphorylation) inhibits KDM4B, leading to increased H3K9me3 and DNA damage at telomeres. H3.3 E31 expression also increases damage at other heterochromatin regions including the pericentric heterochromatin and Y chromosome-specific satellite DNA repeats. We propose that H3.3 S31Ph regulation of KDM4B is required to control heterochromatin accessibility of repetitive DNA and preserve chromatin integrity., (© The Author(s) 2022. Published by Oxford University Press on behalf of Nucleic Acids Research.)

An array of oncogenic histone point mutations have been identified across a number of different cancer studies. It has been suggested that some of these mutant histones can exert their effects by inhibiting epigenetic writers. Here, we report that the H3.3 G34R (glycine to arginine) substitution mutation, found in paediatric gliomas, causes widespread changes in H3K9me3 and H3K36me3 by interfering with the KDM4 family of K9/K36 demethylases. Expression of a targeted single-copy of H3.3 G34R at endogenous levels induced chromatin alterations that were comparable to a KDM4 A/B/C triple-knockout. We find that H3.3 G34R preferentially binds KDM4 while simultaneously inhibiting its enzymatic activity, demonstrating that histone mutations can act through inhibition of epigenetic erasers. These results suggest that histone point mutations can exert their effects through interactions with a range of epigenetic readers, writers and erasers.

ATRX (alpha thalassemia/mental retardation X-linked) complexes with DAXX to deposit histone variant H3.3 into repetitive heterochromatin. Recent genome sequencing studies in cancers have revealed mutations in ATRX and their association with ALT (alternative lengthening of telomeres) activation. Here we report depletion of ATRX in mouse ES cells leads to selective loss in ribosomal RNA gene (rDNA) copy number. Supporting this, ATRX-mutated human ALT-positive tumors also show a substantially lower rDNA copy than ALT-negative tumors. Further investigation shows that the rDNA copy loss and repeat instability are caused by a disruption in H3.3 deposition and thus a failure in heterochromatin formation at rDNA repeats in the absence of ATRX. We also find that ATRX-depleted cells are reduced in ribosomal RNA transcription output and show increased sensitivity to RNA polymerase I (Pol I) transcription inhibitor CX5461. In addition, human ALT-positive cancer cell lines are also more sensitive to CX5461 treatment. Our study provides insights into the contribution of ATRX loss of function to tumorigenesis through the loss of rDNA stability and suggests the therapeutic potential of targeting Pol I transcription in ALT cancers., Competing Interests: The authors declare no conflict of interest., (Copyright © 2018 the Author(s). Published by PNAS.)

AURKB (Aurora Kinase B) is a serine/threonine kinase better known for its role at the mitotic kinetochore during chromosome segregation. Here, we demonstrate that AURKB localizes to the telomeres in mouse embryonic stem cells, where it interacts with the essential telomere protein TERF1. Loss of AURKB function affects TERF1 telomere binding and results in aberrant telomere structure. In vitro kinase experiments successfully identified Serine 404 on TERF1 as a putative AURKB target site. Importantly, in vivo overexpression of S404-TERF1 mutants results in fragile telomere formation. These findings demonstrate that AURKB is an important regulator of telomere structural integrity., (© The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.)

The transmembrane metalloprotease ADAM10 sheds a range of cell surface proteins, including ligands and receptors of the Notch, Eph, and erbB families, thereby activating signaling pathways critical for tumor initiation and maintenance. ADAM10 is thus a promising therapeutic target. Although widely expressed, its activity is normally tightly regulated. We now report prevalence of an active form of ADAM10 in tumors compared with normal tissues, in mouse models and humans, identified by our conformation-specific antibody mAb 8C7. Structure/function experiments indicate mAb 8C7 binds an active conformation dependent on disulfide isomerization and oxidative conditions, common in tumors. Moreover, this active ADAM10 form marks cancer stem-like cells with active Notch signaling, known to mediate chemoresistance. Importantly, specific targeting of active ADAM10 with 8C7 inhibits Notch activity and tumor growth in mouse models, particularly regrowth after chemotherapy. Our results indicate targeted inhibition of active ADAM10 as a potential therapy for ADAM10-dependent tumor development and drug resistance., (© 2016 Atapattu et al.)

Eph receptor tyrosine kinases are critical for cell-cell communication during normal and oncogenic tissue patterning and tumor growth. Somatic mutation profiles of several cancer genomes suggest EphA3 as a tumor suppressor, but its oncogenic expression pattern and role in tumorigenesis remain largely undefined. Here, we report unexpected EphA3 overexpression within the microenvironment of a range of human cancers and mouse tumor xenografts where its activation inhibits tumor growth. EphA3 is found on mouse bone marrow-derived cells with mesenchymal and myeloid phenotypes, and activation of EphA3(+)/CD90(+)/Sca1(+) mesenchymal/stromal cells with an EphA3 agonist leads to cell contraction, cell-cell segregation, and apoptosis. Treatment of mice with an agonistic α-EphA3 antibody inhibits tumor growth by severely disrupting the integrity and function of newly formed tumor stroma and microvasculature. Our data define EphA3 as a novel target for selective ablation of the tumor microenvironment and demonstrate the potential of EphA3 agonists for anticancer therapy., (©2014 American Association for Cancer Research.)

Background: Although rejection rates and short-term graft survival have significantly improved in kidney transplantation with the introduction of calcineurin inhibitor (CNI), cardiovascular disease (CVD) and metabolic complications are being increasingly recognized as important causes of morbidity and mortality. We hypothesize that non-CNI proliferation signal inhibitor (PSI)-based immunosuppressive regimen is associated with improved arterial stiffness after kidney transplantation compared with CNI-based immunosuppressive regimens., Methods: This is a prospective, single-center study of renal transplant (RT) recipients comparing the metabolic, cardiovascular (pulse wave velocity and aortic augmentation index (AI) adjusted for heart rate (AI × 75)), inflammatory cytokines (interleukins (ILs) 6, 12, and 18) and graft-related outcomes at 3 and 15 months posttransplantation between RT recipients maintained on CNI- (CNI-CNI) or PSI-based (CNI-PSI) regimens including sirolimus and everolimus., Results: Fifty and 17 RT recipients maintained on CNI-CNI and CNI-PSI, respectively, were included in this study. Median time to PSI conversion from CNI was 5 months. Compared with CNI-CNI recipients, CNI-PSI recipients had significantly lower fasting blood glucose in nondiabetics (coefficient = -16.2; 95% confidence interval (CI) = -14.4 to -18.0; P < 0.01), lower IL-18 levels (coefficient = -229.16; 95% CI = -343.94 to -114.38; P < 0.01), and lower AI × 75 (coefficient = -5.14; 95% CI = -9.99 to -0.28; P = 0.04) at 15 months posttransplant in the multivariable models., Conclusions: Our study suggests from the elimination of CNI for PSI may lower AIx75 and IL-18, both surrogate markers of CVD, but adequately powered, randomized, controlled studies are required to establish the causal relationship between immunosuppressive agents and CVD risk.

Introduction: End stage renal disease (ESRD) patients have a much higher rate of cardiac disease and cardiac mortality as compared with the general population. Revascularisation such as coronary artery bypass grafting (CABG) may also carry a higher rate of complications and morbidity. We compared our ESRD patients who underwent CABG with the general population and ESRD population., Methods: This is an observational study of ESRD patients who underwent CABG in our centre from 2003-2009 with case-control matching comparison with non-ESRD patients for ICU and hospital stay; and ESRD patients without CABG for survival. Patients with concomitant valvular operation were excluded. The primary outcomes were peri-operative complications and survival., Results: Eleven patients with mean age of 57.5 +/- 8.5 were included. All except 1 were diabetics. One patient had excessive haemorrhage requiring immediate re-thoracotomy, and this was complicated with thrombosed AVF. Four patients experienced intradialytic hypotension postoperatively but all resolved within 1 week. Both ESRD and non-ESRD patients had equal number of ICU stay (3.1 versus 3.2 days, p = 0.906) and hospital stay (7.6 versus 6.9 days, p = 0.538). With average of 3.3 years follow-up (range from 1 to 7 years), 4 deaths were observed but only one from cardiac cause. Both ESRD cohorts with or without CABG have compatible left ventricular mass: 295 +/- 86 vs 343 +/- 113 g (p=0.226) and left ventricular mass: 174 +/- 54 vs. 206 +/- 63 g/m2 (p = 0.157). The outcome of CABG ESRD patients was comparable to matched ESRD patients without CABG with 90.9 % versus 91.9% 1 year survival, 95.5% versus 77.7% 2 year survival, 71.4% versus 70.3% 3 year and 40.0% versus 40.3% at 5 year survival (p = 0.627, 0.386, 0.659 and 0.683 respectively)., Conclusion: CABG in ESRD patients carries an acceptable perioperative complication rate. They have acceptable ICU and hospitalization duration in comparison to non-ESRD patients. Their long term survival was at least as good as matched ESRD patients without CABG.

Autocrine priming of cells by small quantities of constitutively produced type I interferon (IFN) is a well-known phenomenon. In the absence of type I IFN priming, cells display attenuated responses to other cytokines, such as anti-viral protection in response to IFNgamma. This phenomenon was proposed to be because IFNalpha/beta receptor1 (IFNAR1) is a component of the IFNgamma receptor (IFNGR), but our new data are more consistent with a previously proposed model indicating that regulated expression of STAT1 may also play a critical role in the priming process. Initially, we noticed that DNA binding activity of STAT1 was attenuated in c-Jun(-/-) fibroblasts because they expressed lower levels of STAT1 than wild-type cells. However, expression of STAT1 was rescued by culturing c-Jun(-/-) fibroblasts in media conditioned by wild-type fibroblasts suggesting they secreted a STAT1-inducing factor. The STAT1-inducing factor in fibroblast-conditioned media was IFNbeta, as it was inhibited by antibodies to IFNAR1, or when IFNbeta expression was knocked down in wild-type cells. IFNAR1(-/-) fibroblasts, which cannot respond to this priming, also expressed reduced levels of STAT1, which correlated with their poor responses to IFNgamma. The lack of priming in IFNAR1(-/-) fibroblasts was compensated by over-expression of STAT1, which rescued molecular responses to IFNgamma and restored the ability of IFNgamma to induce protective anti-viral immunity. This study provides a comprehensive description of the molecular events involved in priming by type I IFN. Adding to the previous working model that proposed an interaction between type I and II IFN receptors, our work and that of others demonstrates that type I IFN primes IFNgamma-mediated immune responses by regulating expression of STAT1. This may also explain how type I IFN can additionally prime cells to respond to a range of other cytokines that use STAT1 (e.g., IL-6, M-CSF, IL-10) and suggests a potential mechanism for the changing levels of STAT1 expression observed during viral infection., Competing Interests: The authors have declared that no competing interests exist.

IFI 16 is a member of the HIN-200 family of transcriptional regulators that suppress cell growth, modulate the cell cycle and have been linked to cellular differentiation. We hypothesized that the activity of IFI 16 depends on its level of expression and therefore studied the transcriptional activity of the IFI 16 promoter. A discrete sequence within the 5' untranslated region was required for constitutive activity of the promoter and the functional motif within this region was shown to be a consensus AP-1 site. Interestingly, this AP-1 site was also critical for IFN-induced activation of the promoter and consistent with these observations, treatment of cells with IFNgamma resulted in a rapid and robust induction of AP-1 activity that preceded expression of IFI 16. These experiments define the transcriptional mechanisms of IFI 16 gene regulation and provide evidence suggesting that AP-1 activation may be an important event in IFN signaling., (Copyright 2003 Wiley-Liss, Inc.)

INCENP is a chromosomal passenger protein which relocates from the centromere to thel spindle midzone during the metaphase-anaphase transition, ultimately being discarded in the cell midbody at the completion of cytokinesis. Using homologous recombination, we have generated Incenp gene-targeted heterozygous mice that are phenotypically indistinguishable from their wild-type littermates. Intercrossing the hetero-zygotes results in no live-born homozygous Incenp -disrupted progeny, indicating an early lethality. Day 3.5 affected pre-implantation embryos contain large, morphologically abnormal cells that fail to fully develop a blastocoel cavity or thrive in utero and in culture. Chromatin and tubulin immunocytochemical stainings of these and day 2.5 affected embryos reveal a high mitotic index, no discernible metaphase or anaphase stages, complete absence of midbodies, micronuclei formation, morphologically irregular macronuclei with large chromosome complements, multipolar mitotic configurations, binucleated cells, internuclear bridges and abnormal spindle bundling. The phenotype is consistent with a defect in the modulation of microtubule dynamics, severely affecting chromosome segregation and resulting in poorly resolved chromatin masses, aberrant karyokinesis and internuclear bridge formation. These latter occurrences could pose a physical barrier blocking cytokinesis.

CENP-B is a constitutive centromere DNA-binding protein that is conserved in a number of mammalian species and in yeast. Despite this conservation, earlier cytological and indirect experimental studies have provided conflicting evidence concerning the role of this protein in mitosis. The requirement of this protein in meiosis has also not previously been described. To resolve these uncertainties, we used targeted disruption of the Cenpb gene in mouse to study the functional significance of this protein in mitosis and meiosis. Male and female Cenpb null mice have normal body weights at birth and at weaning, but these subsequently lag behind those of the heterozygous and wild-type animals. The weight and sperm content of the testes of Cenpb null mice are also significantly decreased. Otherwise, the animals appear developmentally and reproductively normal. Cytogenetic fluorescence-activated cell sorting and histological analyses of somatic and germline tissues revealed no abnormality. These results indicate that Cenpb is not essential for mitosis or meiosis, although the observed weight reduction raises the possibility that Cenpb deficiency may subtly affect some aspects of centromere assembly and function, and result in reduced rate of cell cycle progression, efficiency of microtubule capture, and/or chromosome movement. A model for a functional redundancy of this protein is presented.