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Mucinous ovarian carcinoma (MOC) is a unique subtype of ovarian cancer with an uncertain etiology, including whether it genuinely arises at the ovary or is metastatic disease from other organs. In addition, the molecular drivers of invasive progression, high-grade and metastatic disease are poorly defined. We perform genetic analysis of MOC across all histological grades, including benign and borderline mucinous ovarian tumors, and compare these to tumors from other potential extra-ovarian sites of origin. Here we show that MOC is distinct from tumors from other sites and supports a progressive model of evolution from borderline precursors to high-grade invasive MOC. Key drivers of progression identified are TP53 mutation and copy number aberrations, including a notable amplicon on 9p13. High copy number aberration burden is associated with worse prognosis in MOC. Our data conclusively demonstrate that MOC arise from benign and borderline precursors at the ovary and are not extra-ovarian metastases., Whether mucinous ovarian carcinoma (MOC) arises from cells at the ovary or from metastases from other primary sites is an unanswered question. Here, Cheasley et al perform a genetic analysis of the disease, showing that MOC arises at the ovary.

Breast cancer (BC) diagnosed after a negative mammogram but prior to the next screening episode is termed an 'interval BC' (IBC). Understanding the molecular differences between IBC and screen-detected BCs (SDBC) could improve mammographic screening and management options. Therefore, we assessed both germline and somatic genomic aberrations in a prospective cohort. Utilising the Lifepool cohort of >54 000 women attending mammographic screening programs, 930 BC cases with screening status were identified (726 SDBC and 204 IBC). Clinico-pathological and family history information were recorded. Germline and tumour DNA were collected where available and sequenced for BC predisposition and driver gene mutations. Compared to SDBC, IBCs were significantly associated with a younger age at diagnosis and tumour characteristics associated with worse prognosis. Germline DNA assessment of BC cases that developed post-enrolment (276 SDBCs and 77 IBCs) for pathogenic mutations in 12 hereditary BC predisposition genes identified 8 carriers (2.27%). The germline mutation frequency was higher in IBC versus SDBC, although not statistically significant (3.90% versus 1.81%, p = 0.174). Comparing somatic genetic features of IBC and SDBC matched for grade, histological subtype and hormone receptor revealed no significant differences, with the exception of higher homologous recombination deficiency scores in IBC, and copy number changes on chromosome Xq in triple negative SDBCs. Our data demonstrates that while IBCs are clinically more aggressive than SDBC, when matched for confounding clinico-pathological features they do not represent a unique molecular class of invasive BC, but could be a consequence of timing of tumour initiation and mammographic screening. Copyright © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Mammographic density (MD) influences breast cancer risk, but how this is mediated is unknown. Molecular differences between breast cancers arising in the context of the lowest and highest quintiles of mammographic density may identify the mechanism through which MD drives breast cancer development. Women diagnosed with invasive or in situ breast cancer where MD measurement was also available (n = 842) were identified from the Lifepool cohort of >54,000 women participating in population-based mammographic screening. This group included 142 carcinomas in the lowest quintile of MD and 119 carcinomas in the highest quintile. Clinico-pathological and family history information were recorded. Tumor DNA was collected where available (n = 56) and sequenced for breast cancer predisposition and driver gene mutations, including copy number alterations. Compared to carcinomas from low-MD breasts, those from high-MD breasts were significantly associated with a younger age at diagnosis and features associated with poor prognosis. Low- and high-MD carcinomas matched for grade, histological subtype, and hormone receptor status were compared for somatic genetic features. Low-MD carcinomas had a significantly increased frequency of TP53 mutations, higher homologous recombination deficiency, higher fraction of the genome altered, and more copy number gains on chromosome 1q and losses on 17p. While high-MD carcinomas showed enrichment of tumor-infiltrating lymphocytes in the stroma. The data demonstrate that when tumors were matched for confounding clinico-pathological features, a proportion in the lowest quintile of MD appear biologically distinct, reflective of microenvironment differences between the lowest and highest quintiles of MD.

Diet is the cornerstone of treatment in diabetes and dietary advice should be tailored to the individual and their circumstances. This article focuses on patients with diabetes who are identified as being at risk of malnutrition and community nurses are ideally placed to meet patients' continuum of health needs. Emphasis should be put on nutritional support, encouraging food fortification (some recipes will need adapting), full-fat products and high-energy snacks. Diabetes treatment will need to be reviewed regularly to reflect changes in the patient's needs. Glycaemic targets need to be agreed with the patient and those at risk of hypoglycaemia identified. Strategies should be put in place for minimising risk and a clear treatment plan implemented. In cases where the risk of malnutrition is resolved, the patient and family may need support returning to previous dietary recommendations.

There are two predominant theories for lumen formation in tissue morphogenesis: cavitation driven by cell death, and membrane separation driven by epithelial polarity. To define the mechanism of lumen formation in prostate acini, we examined both theories in several cell lines grown in three-dimensional (3D) Matrigel culture. Lumen formation occurred early in culture and preceded the expression of cell death markers for apoptosis (active caspase 3) and autophagy (LC-3). Active caspase 3 was expressed by very few cells and inhibition of apoptosis did not suppress lumen formation. Despite LC-3 expression in all cells within a spheroid, this was not associated with cell death. However, expression of a prostate-secretory protein coincided with lumen formation and subsequent disruption of polarized fluid movement led to significant inhibition of lumen formation. This work indicates that lumen formation is driven by the polarized movement of fluids and proteins in 3D prostate epithelial models and not by cavitation.

DNA sequences that control transcription are frequently located in the noncoding portion of the mammalian genome (The ENCODE Project Consortium 2012). These elements can act over long distances (Noonan and McCallion 2010). The identification of these control elements is important for elucidating human genetic disease since genome-wide association studies regularly point to noncoding regions as candidates in disease etiology (Manolio 2010). One of the proteins that contributes to the regulation of gene expression across the genome is CTCF (CCCTC-binding factor), a protein with 11 zinc fingers (Filippova et al. 1996) and multiple regulatory functions (Ohlsson 2001; Gaszner and Felsenfeld 2006). CTCF can act as an insulator by blocking interactions between enhancers and promoters (Bell et al. 1999), it can directly regulate chromosomal interactions (Yusufzai and Felsenfeld 2004; Hadjur et al. 2009), and it can act as an enhancer of transcription (Kuzmin et al. 2005). CTCF binds regions of DNA with high sequence specificity and is sensitive to DNA methylation, having a lower binding affinity for methylated DNA (Mukhopadhyay et al. 2004). The canonical consensus binding motif of CTCF and the sites of CTCF binding are evolutionarily conserved between mammals and birds (Martin et al. 2011; Schmidt et al. 2012). In vitro assays have shown that CTCF can use different combinations of its zinc fingers to bind to distinct DNA sequences (Filippova et al. 1996). CTCF interacts with a variety of other factors. In particular, the cohesin complex, best known for its role in mediating sister-chromatid cohesion during cell division, has been found to frequently colocalize with CTCF during interphase (Parelho et al. 2008; Rubio et al. 2008; Wendt et al. 2008; Xiao et al. 2011) with consequences for gene expression. At specific loci, cohesin is required for cell-type-specific long-range chromosomal interactions in cis during cellular differentiation (Hadjur et al. 2009). Genomic imprinting refers to the parental allele-specific transcription of a subset of genes in mammals and flowering plants (Reik and Walter 2001; da Rocha et al. 2008). Roughly 140 transcripts are known to be imprinted in mammals (Schulz et al. 2008). Imprinting is controlled by epigenetic modifications that differ between the two parental genomes, including differences in DNA methylation (Li et al. 1993). Imprinted genes can occur in large, coordinately regulated clusters exemplified by the Gnas locus (Peters and Williamson 2007); they can form small domains such as the Mcts2/H13 locus (Wood et al. 2008) that are comprised of only two genes (McCole and Oakey 2008), or they can be singletons like Impact (Hagiwara et al. 1997). In all cases, their parental allele-specific expression is ultimately due to an imprinting control region (ICR), a region of DNA that is differentially methylated between the parental alleles. The parental allele-specific methylation of a differentially methylated region (DMR) is in most cases the consequence of the sex-specific epigenetic reprogramming of the parental germ cells (Edwards and Ferguson-Smith 2007; Bartolomei 2009). In addition, DMRs are actively protected from post-fertilization epigenetic reprogramming (Quenneville et al. 2012) and, thus, persist into adulthood. In some cases, the parental allele-specific methylation of a DMR is set up post-fertilization during early embryogenesis (somatic DMRs) (Kobayashi et al. 2012). DMRs with a direct germline origin are referred to as germline DMRs (gDMRs). Disruption of imprinted gene expression after deletion of a DMR is considered evidence that the latter functions as an ICR. There are 22 well-established gDMRs in mouse, of which 19 are maternally methylated and three are paternally methylated. Many mechanisms exist to “translate” allele-specific methylation into differential gene expression, including differential protein binding (Lewis and Reik 2006). CTCF has long been associated with genomic imprinting due to its selective binding of the unmethylated maternal allele of the Igf2/H19 ICR resulting in parent-of-origin-specific expression of Igf2 and H19 in mouse and human (Bell and Felsenfeld 2000; Hark et al. 2000; Kanduri et al. 2000; Fedoriw et al. 2004; Szabo et al. 2004). CTCF has been studied at several other imprinted loci, and it binds the unmethylated allele at the gDMRs of Rasgrf1, Peg13, Kcnq1ot1 (Yoon et al. 2005; Fitzpatrick et al. 2007; Singh et al. 2011), and Grb10 (Hikichi et al. 2003; Mukhopadhyay et al. 2004). CTCF-mediated regulation is postulated to be one of two major control mechanisms operating at ICRs (Lewis and Reik 2006; Kim et al. 2009). Cohesin also has been linked to imprinting through its association with CTCF at the H19/Igf2 and Kcnq1ot1 DMRs (Stedman et al. 2008; Lin et al. 2011), and a role for cohesin in the allele-specific organization of higher-order chromatin has been proposed (Nativio et al. 2009). Here we present the first comprehensive analysis of allele-specific CTCF and cohesin binding at all known DMRs in a single tissue, providing an unbiased assessment of the extent to which CTCF and cohesin are involved in imprinting control. Genome-wide ChIP-seq in mouse ES cells (Chen et al. 2008; Kagey et al. 2010) and human cells (Kim et al. 2007b) has shown that CTCF and cohesin bind tens of thousands of discrete sites across the genome, and CTCF binding is enriched in and near genes, consistent with a role in the control of gene expression. Mouse embryonic stem (ES) cell data identify CTCF and cohesin binding at the gDMRs of Peg13, Zim2 (Peg3), Peg10, Grb10, and Mest but not at the H19/Igf2 ICR, even though CTCF is known to be important for imprinting regulation at this domain. Imprinting is dispensable in ES cells, where loss of imprinting frequently occurs without affecting viability in culture (Kim et al. 2007a; Rugg-Gunn et al. 2007; Frost et al. 2011). The same is true for Dnmt1−/−, Dnmt3a−/−, Dnmt3b−/− triple knockout mouse ES cells that consequently lack all DNA methylation imprints but yet are viable (Tsumura et al. 2006). In contrast, a differentiated tissue where imprinting plays an important role is the brain (Davies et al. 2007), and this is supported by multiple lines of evidence. Firstly, the human imprinting disorders Prader-Willi syndrome and Angelman syndrome present with behavioral and neurodevelopmental phenotypes (Cassidy et al. 2000; Lossie et al. 2001; Williams et al. 2006); secondly, of the ∼140 imprinted gene transcripts in the mouse, more than 50 are expressed in brain (Wilkins 2008); thirdly, the disruption of certain mouse imprinted genes, including Peg3 (Li et al. 1999), Mest (Lefebvre et al. 1998), Nesp55 (Plagge et al. 2005), and Grb10 (Garfield et al. 2011), results in behavioral phenotypes; finally, genome-wide allele-specific studies of transcription in mouse brain suggest that this tissue is a focus for imprinted gene expression (Gregg et al. 2010a,b; DeVeale et al. 2012). Our analyses of CTCF and cohesin binding in mouse brain are based on ChIP-seq data of high quality and an order of magnitude higher read depth than existing data. The use of reciprocal inter-subspecies hybrid mice enabled independent interrogation of the parental alleles in terms of CTCF and cohesin binding in unprecedented detail. We examined postnatal day 21 (P21) mouse brain, a time point in development shortly after the growth spurt in neurogenesis that occurs in the first 2 wk of postnatal development (Lyck et al. 2007). In the adult mouse brain, ∼56% of cells are neurons and 44% are nonneuronal cells (Fu et al. 2012). Neurons and the principle type of nonneuronal cells, the macroglia, both derive from the neuroepithelium. These data are representative of adult rather than immature brain cell types and are unaffected by long-term aging effects.

Malnutrition is often unrecognised in people with diabetes but community nurses can help educate patients and alert specialists if required.

Nucleic acid sequence capture extraction was coupled with LightCycler PCR amplification and product detection using real-time fluorescence for rapid, definitive detection of Mycobacterium bovis in lymph node specimens from 38 cattle with bovine tuberculosis lesions. PCR amplification of sequence-captured DNA using both a conventional heating block thermocycler and a LightCycler thermocycler was compared with culture and histopathological analyses. Conventional PCR enabled detection of 26 of 28 culture-positive specimens (93%) in approximately 9 h, and the LightCycler PCR detected 20 of 28 culture-positive specimens (71%) in only 30 min. Specific confirmation of Mycobacterium tuberculosis complex DNA was achieved by LightCycler PCR amplification using Syb Green 1 and an M. tuberculosis complex-specific Cy5-labeled fluorescence resonance energy transfer probe. The system described here enabled rapid and specific laboratory confirmation of bovine tuberculosis, and this is the first report of the detection of M. bovis in tissues using LightCycler PCR. The fluorescence technology used in the study has potential to allow development of a high-throughput molecular diagnostic test for bovine tuberculosis.

Subtraction hybridization was used to identify sequences of Mycobacterium bovis DNA which might be of diagnostic value. Genomic DNA from Mycobacterium avium, isolated commonly from cattle and whose tuberculin is used in the comparative intradermal tuberculin test, was subtracted from M. bovis genomic DNA. A novel sequence, of 131 bp, which appears to be Mycobacterium tuberculosis complex-specific was identified. The specificity of this sequence was stringently tested by a probe and polymerase chain reaction (PCR) assay. Nucleotide identity determination and sequence comparisons revealed that the 131-bp sequence is located directly upstream of a potential isocitrate dehydrogenase (IDH) coding gene and may be of diagnostic value, enabling differentiation of M. tuberculosis complex mycobacteria from other mycobacterial species.

In 1973, a Rhodesian veterinarian, Richard Smith, documented a mycobacterial skin infection in a Doberman and a Rhodesian Ridgeback dog that was characterised by variably sized subcutaneous nodules. It was thought at first that these dogs may have had tuberculosis and, because of public health considerations, they were euthanased and subjected to postmortem examination. There was no internal organ involvement at necropsy and, although acid-fast bacilli (AFB) were abundant in the lesions, culture was negative for the tubercle bacillus. Similar cases were recorded soon thereafter in an Australian veterinary discussion forum, although the infection was not subjected to systematic investigation until the end of the 20th century. The disease was given the name ?canine leprosy? by some veterinary dermatologists, but the alternative name canine leproid granuloma syndrome (CLGS) was later suggested by an Australian veterinarian David Watson. It is now clear that leproid granulomas are not uncommon and indeed are by far the most frequently encountered mycobacterial disease of dogs in Australia.