67 research outputs found

    Mll5 Is Required for Normal Spermatogenesis

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    Mll5 is currently a member of the Mll family of SET domain histone methyltransferase proteins but studies have also showed that it could be part of the SET3 branch of proteins. Recently, constitutive knock out animal studies have shown that Mll5 is required for proper haematopoietic stem cell differentiation, and loss of Mll5 results in synthetic lethality for genome de-methylation. Mll5 deficient male mice are infertile and here we analyse the consequences of Mll5 deficiency for spermatogenesis.Mll5 deficient male mice, but not female mice, are infertile. Here we show using RNA in-situ hybridization that Mll5 is expressed in the germ cells of the testes of wild type mice. Consistent with the expression of Mll5, we demonstrate by electron microscopy, video microscopy and in vitro fertilisation techniques that Mll5 deficient mice have defects in terminal maturation and packaging of sperm. The defects seen include detachment of the acrosomal cap and impaired excess cytoplasm removal. Functional tests of sperm motility show a lack of progressive motility of spermatozoa from Mll5 deficient animals. None of these defects could be rescued by in vitro fertilization. Using microarray analysis we show that transcripts implicated in spermatogenesis are dysregulated.Our data demonstrate a clear role of Mll5 in mammalian spermatogenesis at the level of terminal differentiation providing further support for its classification in the SET3 branch of proteins. Moreover, this study identifies Tlk2, Utx, Gpr64, Sult4a1, Rap2ip, Vstm2 and HoxA10 as possible Mll5 targets that together may account for the observed spermatozoa maturation defects

    The testosterone-dependent and independent transcriptional networks in the hypothalamus of Gpr54 and Kiss1 knockout male mice are not fully equivalent.

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    BACKGROUND: Humans and mice with loss of function mutations in GPR54 (KISS1R) or kisspeptin do not progress through puberty, caused by a failure to release GnRH. The transcriptional networks regulated by these proteins in the hypothalamus have yet to be explored by genome-wide methods. RESULTS: We show here, using 1 million exon mouse arrays (Exon 1.0 Affymetrix) and quantitative polymerase chain reaction (QPCR) validation to analyse microdissected hypothalamic tissue from Gpr54 and Kiss1 knockout mice, the extent of transcriptional regulation in the hypothalamus. The sensitivity to detect important transcript differences in microdissected RNA was confirmed by the observation of counter-regulation of Kiss1 expression in Gpr54 knockouts and confirmed by immunohistochemistry (IHC). Since Gpr54 and Kiss1 knockout animals are effectively pre-pubertal with low testosterone (T) levels, we also determined which of the validated transcripts were T-responsive and which varied according to genotype alone. We observed four types of transcriptional regulation (i) genotype only dependent regulation, (ii) T only dependent regulation, (iii) genotype and T-dependent regulation with interaction between these variables, (iv) genotype and T-dependent regulation with no interaction between these variables. The results implicate for the first time several transcription factors (e.g. Npas4, Esr2), proteases (Klk1b22), and the orphan 10-transmembrane transporter TMEM144 in the biology of GPR54/kisspeptin function in the hypothalamus. We show for the neuronal activity regulated transcription factor NPAS4, that distinct protein over-expression is seen in the hypothalamus and hippocampus in Gpr54 knockout mice. This links for the first time the hypothalamic-gonadal axis with this important regulator of inhibitory synapse formation. Similarly we confirm TMEM144 up-regulation in the hypothalamus by RNA in situ hybridization and western blot. CONCLUSIONS: Taken together, global transcriptional profiling shows that loss of GPR54 and kisspeptin are not fully equivalent in the mouse hypothalamus.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

    Ciliated muconodular papillary tumors of the lung with KRAS/BRAF/AKT1 mutation

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    Background: Ciliated muconodular papillary tumors (CMPTs) are newly recognized rare peripheral lung nodules that are histologically characterized by ciliated columnar, goblet, and basal cells. Although recent studies have shown that CMPTs constitute a neoplastic disease, the complete histogenesis of CMPTs is not fully understood and molecular data are limited. Methods: We reviewed four cases of CMPT and performed immunohistochemical and genomic analyses to establish CMPT profiles. Results: All cases were positive for hepatocyte nuclear factor-4α and mucin 5B and negative for programmed death ligand 1 expression, as determined by immunohistochemistry. The genetic analysis revealed three pathogenic mutations (BRAF V600E, AKT1 E17K, and KRAS G12D), with the KRAS mutation reported here for the first time. Conclusion: Histological and genetic profiles indicate that CMPTs are likely neoplastic and exhibit features similar to mucinous adenocarcinoma. This suggests that some CMPTs may be a precursor lesion of mucinous adenocarcinoma

    Effect of remote ischaemic conditioning on clinical outcomes in patients with acute myocardial infarction (CONDI-2/ERIC-PPCI): a single-blind randomised controlled trial.

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    BACKGROUND: Remote ischaemic conditioning with transient ischaemia and reperfusion applied to the arm has been shown to reduce myocardial infarct size in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). We investigated whether remote ischaemic conditioning could reduce the incidence of cardiac death and hospitalisation for heart failure at 12 months. METHODS: We did an international investigator-initiated, prospective, single-blind, randomised controlled trial (CONDI-2/ERIC-PPCI) at 33 centres across the UK, Denmark, Spain, and Serbia. Patients (age >18 years) with suspected STEMI and who were eligible for PPCI were randomly allocated (1:1, stratified by centre with a permuted block method) to receive standard treatment (including a sham simulated remote ischaemic conditioning intervention at UK sites only) or remote ischaemic conditioning treatment (intermittent ischaemia and reperfusion applied to the arm through four cycles of 5-min inflation and 5-min deflation of an automated cuff device) before PPCI. Investigators responsible for data collection and outcome assessment were masked to treatment allocation. The primary combined endpoint was cardiac death or hospitalisation for heart failure at 12 months in the intention-to-treat population. This trial is registered with ClinicalTrials.gov (NCT02342522) and is completed. FINDINGS: Between Nov 6, 2013, and March 31, 2018, 5401 patients were randomly allocated to either the control group (n=2701) or the remote ischaemic conditioning group (n=2700). After exclusion of patients upon hospital arrival or loss to follow-up, 2569 patients in the control group and 2546 in the intervention group were included in the intention-to-treat analysis. At 12 months post-PPCI, the Kaplan-Meier-estimated frequencies of cardiac death or hospitalisation for heart failure (the primary endpoint) were 220 (8·6%) patients in the control group and 239 (9·4%) in the remote ischaemic conditioning group (hazard ratio 1·10 [95% CI 0·91-1·32], p=0·32 for intervention versus control). No important unexpected adverse events or side effects of remote ischaemic conditioning were observed. INTERPRETATION: Remote ischaemic conditioning does not improve clinical outcomes (cardiac death or hospitalisation for heart failure) at 12 months in patients with STEMI undergoing PPCI. FUNDING: British Heart Foundation, University College London Hospitals/University College London Biomedical Research Centre, Danish Innovation Foundation, Novo Nordisk Foundation, TrygFonden

    Formalin fixation increases deamination mutation signature but should not lead to false positive mutations in clinical practice.

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    Genomic analysis of cancer tissues is an essential aspect of personalized oncology treatment. Though it has been suggested that formalin fixation of patient tissues may be suboptimal for molecular studies, this tissue processing approach remains the industry standard. Therefore clinical molecular laboratories must be able to work with formalin fixed, paraffin embedded (FFPE) material. This study examines the effects of pre-analytic variables introduced by routine pathology processing on specimens used for clinical reports produced by next-generation sequencing technology. Tissue resected from three colorectal cancer patients was subjected to 2, 15, 24, and 48 hour fixation times in neutral buffered formalin. DNA was extracted from all tissues twice, once with uracil-N-glycosylase (UNG) treatment to counter deamination effects, and once without. Of note, deamination events at methylated cytosine, as found at CpG sites, remains unaffected by UNG. After extraction a two-step PCR targeted sequencing method was performed using the Illumina MiSeq and the data was analyzed via a custom-built bioinformatics pipeline, including filtration of reads with mapping quality T/A mutations that is not represented in DNA treated with UNG. This suggests these errors may be due to deamination events triggered by a longer fixation time. However the allelic frequency of these events remained below the limit of detection for reportable mutations in this assay (<2%). We do however recommend that suspected intratumoral heterogeneity events be verified by re-sequencing the same FFPE block

    Kisspeptin and GPR54 immunoreactivity in a cohort of 518 patients defines favourable prognosis and clear cell subtype in ovarian carcinoma

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    Background: Kisspeptins and their G-protein coupled receptor, GPR54 are required for GnRH release and have been associated with anti-metastatic tumour cell behaviour in model systems. The latter might suggest that their overexpression would be associated with a better prognosis in cancer. However, kisspeptin/GPR54 interactions (autocrine, paracrine, and/or endocrine) could also impact tumour behaviour in a negative manner. Here, for the first time, we associate the immunoreactivity of the kisspeptin/GPR54 ligand-receptor pair with favourable prognosis in a large cohort of ovarian carcinomas. Methods Immunohistochemical analysis for kisspeptin and GPR54 was performed on a tissue microarray (TMA) consisting of 518 early stage ovarian carcinomas, all with linked clinical outcome data. The TMA was scored using a staining intensity scale of 0 (negative), +1 (mild-moderate), and +2 (strong). Strong staining cases were considered either kisspeptin or GPR54 positive and designated as 1, while all other cases were considered negative and designated 0. All statistical analysis was conducted using two-sided tests and a p value equal to or less than 0.05 was considered significant. Results Kisspeptin and GPR54 immunoreactive cases show a favourable prognosis in univariable disease specific survival (p = 0.0023, p = 0.0092), as well as in overall survival (p = 0.0006, p = 0.0002). Furthermore, kisspeptin is an independent marker for favourable prognosis as determined by multivariable disease specific (p = 0.0046) and overall survival analysis (p = 0.0170), while GPR54 is an independent marker for overall survival only (p = 0.0303). Both kisspeptin positive and GPR54 positive cases are strongly associated with the ovarian carcinoma clear cell subtype (p < 0.0001, p < 0.0001), and GPR54 is significantly associated with favourable prognosis in overall survival within the clear cell subtype (p = 0.0102). Conclusion Kisspeptin and GPR54 immunoreactivity are significantly associated with favourable prognosis in both disease specific and overall survival, as well as being significantly associated with the clear cell ovarian carcinoma subtype, thereby creating the first independent prognostic biomarkers specific for ovarian clear cell carcinomas.Medicine, Department ofMedicine, Faculty ofObstetrics and Gynaecology, Department ofPathology and Laboratory Medicine, Department ofNon UBCReviewedFacult

    Ovarian carcinoma subtypes are different diseases: implications for biomarker studies.

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    BACKGROUND: Although it has long been appreciated that ovarian carcinoma subtypes (serous, clear cell, endometrioid, and mucinous) are associated with different natural histories, most ovarian carcinoma biomarker studies and current treatment protocols for women with this disease are not subtype specific. With the emergence of high-throughput molecular techniques, distinct pathogenetic pathways have been identified in these subtypes. We examined variation in biomarker expression rates between subtypes, and how this influences correlations between biomarker expression and stage at diagnosis or prognosis. METHODS AND FINDINGS: In this retrospective study we assessed the protein expression of 21 candidate tissue-based biomarkers (CA125, CRABP-II, EpCam, ER, F-Spondin, HE4, IGF2, K-Cadherin, Ki-67, KISS1, Matriptase, Mesothelin, MIF, MMP7, p21, p53, PAX8, PR, SLPI, TROP2, WT1) in a population-based cohort of 500 ovarian carcinomas that was collected over the period from 1984 to 2000. The expression of 20 of the 21 biomarkers differs significantly between subtypes, but does not vary across stage within each subtype. Survival analyses show that nine of the 21 biomarkers are prognostic indicators in the entire cohort but when analyzed by subtype only three remain prognostic indicators in the high-grade serous and none in the clear cell subtype. For example, tumor proliferation, as assessed by Ki-67 staining, varies markedly between different subtypes and is an unfavourable prognostic marker in the entire cohort (risk ratio [RR] 1.7, 95% confidence interval [CI] 1.2%-2.4%) but is not of prognostic significance within any subtype. Prognostic associations can even show an inverse correlation within the entire cohort, when compared to a specific subtype. For example, WT1 is more frequently expressed in high-grade serous carcinomas, an aggressive subtype, and is an unfavourable prognostic marker within the entire cohort of ovarian carcinomas (RR 1.7, 95% CI 1.2%-2.3%), but is a favourable prognostic marker within the high-grade serous subtype (RR 0.5, 95% CI 0.3%-0.8%). CONCLUSIONS: The association of biomarker expression with survival varies substantially between subtypes, and can easily be overlooked in whole cohort analyses. To avoid this effect, each subtype within a cohort should be analyzed discretely. Ovarian carcinoma subtypes are different diseases, and these differences should be reflected in clinical research study design and ultimately in the management of ovarian carcinoma
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