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The genesis of extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) is driven by oncogenic co-operation among immunological stimulations and acquired genetic changes. We previously identified recurrent CCR6 mutations in MALT lymphoma, with majority predicted to result in truncated proteins lacking the phosphorylation motif important for receptor desensitization. Functional consequences of these mutational changes, the molecular mechanisms of CCR6 activation and how this receptor signaling contributes to MALT lymphoma development remain to be investigated. In the present study, we demonstrated that these mutations impaired CCR6 receptor internalization and were activating changes, being more potent in apoptosis resistance, malignant transformation, migration and intracellular signaling, particularly in the presence of the ligands CCL20, HBD2 (human beta defensin 2) and HD5 (human alpha defensin 5). CCR6 was highly expressed in malignant B cells irrespective of the lymphoma sites. HBD2 and CCL20 were constitutively expressed by the duct epithelial cells of salivary glands, and also those involved in lymphoepithelial lesions (LEL) in salivary gland MALT lymphoma. While in the gastric setting, HBD2, and HD5, to a less extent CCL20, were highly expressed in epithelial cells of pyloric and intestinal metaplasia respectively including those involved in LEL, which are adaptive responses to chronic Helicobacter pylori infection. These findings suggest that CCR6 signaling is most likely active in MALT lymphoma, independent of its mutation status. The observations explain why the emergence of malignant B cells and their clonal expansion in MALT lymphoma are typically around LEL, linking the innate immune responses to lymphoma genesis.

Summary: Background: Screening for Barrett's oesophagus relies on endoscopy, which is invasive and few who undergo the procedure are found to have the condition. We aimed to use machine learning techniques to develop and externally validate a simple risk prediction panel to screen individuals for Barrett's oesophagus. Methods: In this prospective study, machine learning risk prediction in Barrett's oesophagus (MARK-BE), we used data from two case-control studies, BEST2 and BOOST, to compile training and validation datasets. From the BEST2 study, we analysed questionnaires from 1299 patients, of whom 880 (67·7%) had Barrett's oesophagus, including 40 with invasive oesophageal adenocarcinoma, and 419 (32·3%) were controls. We randomly split (6:4) the cohort using a computer algorithm into a training dataset of 776 patients and a testing dataset of 523 patients. We compiled an external validation cohort from the BOOST study, which included 398 patients, comprising 198 patients with Barrett's oesophagus (23 with oesophageal adenocarcinoma) and 200 controls. We identified independently important diagnostic features of Barrett's oesophagus using the machine learning techniques information gain and correlation-based feature selection. We assessed multiple classification tools to create a multivariable risk prediction model. Internal validation of the model using the BEST2 testing dataset was followed by external validation using the BOOST external validation dataset. From these data we created a prediction panel to identify at-risk individuals. Findings: The BEST2 study included 40 diagnostic features. Of these, 19 added information gain but after correlation-based feature selection only eight showed independent diagnostic value including age, sex, cigarette smoking, waist circumference, frequency of stomach pain, duration of heartburn and acidic taste, and taking antireflux medication, of which all were associated with increased risk of Barrett's oesophagus, except frequency of stomach pain, with was inversely associated in a case-control population. Logistic regression offered the highest prediction quality with an area under the receiver-operator curve (AUC) of 0·87 (95% CI 0·84–0·90; sensitivity set at 90%; specificity of 68%). In the testing dataset, AUC was 0·86 (0·83–0·89; sensitivity set at 90%; specificity of 65%). In the external validation dataset, the AUC was 0·81 (0·74–0·84; sensitivity set at 90%; specificity of 58%). Interpretation: Our diagnostic model offers valid predictions of diagnosis of Barrett's oesophagus in patients with symptomatic gastro-oesophageal reflux disease, assisting in identifying who should go forward to invasive confirmatory testing. Our predictive panel suggests that overweight men who have been taking antireflux medication for a long time might merit particular consideration for further testing. Our risk prediction panel is quick and simple to administer but will need further calibration and validation in a prospective study in primary care. Funding: Charles Wolfson Charitable Trust and Guts UK.

Tumours with homologous recombination (HR) defects become sensitive to PARPi. Here, the authors show that androgen receptor (AR) regulates HR and AR inhibition activates the PARP pathway in vivo, thus inhibition of both AR and PARP is required for effective treatment of high risk prostate cancer.

The purpose of this paper is to study the dynamic characteristics of flexible base asphalt pavement in use, based on the theoretical analysis of fatigue performance of asphalt pavement. The accelerated loading test of flexible asphalt pavement is carried out by using the heavy vehicle simulation equipment. Under the condition of controlling the axle load and speed, the asphalt bottom strain of the test road was collected. Regression analysis was carried out on the correlation among the temperature, the loading times and the tensile strain of the asphalt layer. It is found that the bottom strain of the flexible base asphalt pavement is proportional to the axle load and the temperature, nevertheless it's inversely proportional to the axle load speed. The conclusion contributes to the fatigue damage analysis of the flexible base pavement. [ABSTRACT FROM AUTHOR]

Microarray comparison of the transcriptomes of human adrenal zona glomerulosa (ZG) and zona fasciculata found several ZG-specific genes that negatively regulate aldosterone secretion. The third and most significantly upregulated ZG-gene (19.9-fold compared with zona fasciculata, P=6.58×10-24) was ANO4, a putative Ca2+-activated chloride channel. We have investigated the role of ANO4 in human adrenal, and whether it functions like the prototype anoctamin, ANO1. We evaluated ANO4 mRNA and protein expression in human adrenal by qPCR and immunohistochemistry, compared the effects of ANO4 and ANO1 overexpression on baseline and stimulated aldosterone secretion and cell proliferation in H295R cells, and analyzed ANO4 activity as a Ca2+-activated chloride channel in comparison with other anoctamins by a fluorescence-based functional assay. The expression of ANO4 in ZG was confirmed by qPCR as 23.21-fold upregulated compared with zona fasciculata (n=18; P=4.93×10-7). Immunohistochemistry found cytoplasmic, ZG-selective expression of ANO4 (anoctamin 4) protein. ANO4 overexpression in H295R cells attenuated calcium-mediated aldosterone secretion and cell proliferation in comparison to controls. The latter effects were in a different direction to those of ANO1. The functional assay showed that, in contrast to ANO1, ANO4 expression results in low levels of calcium-dependent anion transport. In conclusion, ANO4 is one of the most highly expressed genes in ZG. It attenuates stimulated aldosterone secretion and cell proliferation. Although belonging to a family of Ca2+-activated chloride channels, it does not generate significant plasma membrane chloride channel activity. [ABSTRACT FROM AUTHOR]

Emerging data demonstrate homologous recombination (HR) defects in castration-resistant prostate cancers, rendering these tumours sensitive to PARP inhibition. Here we demonstrate a direct requirement for the androgen receptor (AR) to maintain HR gene expression and HR activity in prostate cancer. We show that PARP-mediated repair pathways are upregulated in prostate cancer following androgen-deprivation therapy (ADT). Furthermore, upregulation of PARP activity is essential for the survival of prostate cancer cells and we demonstrate a synthetic lethality between ADT and PARP inhibition in vivo. Our data suggest that ADT can functionally impair HR prior to the development of castration resistance and that, this potentially could be exploited therapeutically using PARP inhibitors in combination with androgen-deprivation therapy upfront in advanced or high-risk prostate cancer. [ABSTRACT FROM AUTHOR]

Heterogeneity among aldosterone-producing adenomas (APAs) has been highlighted by the discovery of somatic mutations. KCNJ5 mutations predominate in large zona fasciculata (ZF)-like APAs; mutations in CACNA1D, ATP1A1, ATP2B3, and CTNNB1 are more likely to be found in small zona glomerulosa (ZG)-like APAs. Microarray comparison of KCNJ5 mutant versus wild-type APAs revealed significant differences in transcriptomes. NEFM, encoding a neurofilament subunit which is a D1R (dopamine D1 receptor)-interacting protein, was 4-fold upregulated in ZG-like versus ZF-like APAs and 14-fold more highly expressed in normal ZG versus ZF. Immunohistochemistry confirmed selective expression of NEFM (neurofilament medium) polypeptide in ZG and in ZG-like APAs. Silencing NEFM in adrenocortical H295R cells increased basal aldosterone secretion and cell proliferation; silencing also amplified aldosterone stimulation by the D1R agonist, fenoldopam, and inhibition by the D1R antagonist, SCH23390. NEFM coimmunoprecipitated with D1R, and its expression was stimulated by fenoldopam. Immunohistochemistry for D1R was mainly intracellular in ZG-like APAs but membranous in ZF-like APAs. Aldosterone secretion in response to fenoldopam in primary cells from ZF-like APAs was higher than in cells from ZG-like APAs. Transfection of mutant KCNJ5 caused a large reduction in NEFM expression in H295R cells. We conclude that NEFM is a negative regulator of aldosterone production and cell proliferation, in part by facilitating D1R internalization from the plasma membrane. Downregulation of NEFM in ZF-like APAs may contribute to a D1R/D2R imbalance underlying variable pharmacological responses to dopaminergic drugs among patients with APAs. Finally, taken together, our data point to the possibility that ZF-like APAs are in fact ZG in origin. [ABSTRACT FROM AUTHOR]

Primary aldosteronism is a common cause of hypertension, which becomes refractory if undiagnosed, but potentially curable when caused by an aldosterone-producing adenoma (APA). The discovery of somatic mutations and differences in clinical presentations led to recognition of small but common zona glomerulosa (ZG)-like adenomas, distinct from classical large zona fasciculata-like adenomas. The inverse correlation between APA size and aldosterone synthase expression prompted us to undertake a systematic study of genotype-phenotype relationships. After a microarray comparing tumor subtypes, in which NPNT (nephronectin) was the most highly (>12-fold) upregulated gene in ZG-like APAs, we aimed to determine its role in physiological and pathological aldosterone production. NPNT was identified by immunohistochemistry as a secreted matrix protein expressed exclusively around aldosterone-producing glomeruli in normal adrenal ZG and in aldosterone-dense ZG-like APAs; the highest expression was in ZG-like APAs with gain-of-function CTNNB1 mutations, whose removal cured hypertension in our patients. NPNT was absent from normal zona fasciculata, zona fasciculata-like APAs, and ZG adjacent to an APA. NPNT production was regulated by canonical Wnt pathway, and NPNT overexpression or silencing increased or reduced aldosterone, respectively. NPNT was proadhesive in primary adrenal and APA cells but antiadhesive and antiapoptotic in immortalized adrenocortical cells. The discovery of NPNT in the adrenal helped recognition of a common subtype of APAs and a pathway by which Wnt regulates aldosterone production. We propose that this arises through NPNT's binding to cell-surface integrins, stimulating cell-cell contact within glomeruli, which define ZG. Therefore, NPNT or its cognate integrin could present a novel therapeutic target. [ABSTRACT FROM AUTHOR]

Common somatic mutations in CACNAID and ATP1A1 may define a subgroup of smaller, zona glomerulosa (ZG)- like aldosterone-producing adenomas. We have therefore sought signature ZG genes, which may provide insight into the frequency and pathogenesis of ZG-like aldosterone-producing adenomas. Twenty-one pairs of zona fasciculata and ZG and 14 paired aldosterone-producing adenomas from 14 patients with Conn's syndrome and 7 patients with pheochromocytoma were assayed by the Affymetrix Human Genome U133 Plus 2.0 Array. Validation by quantitative real-time polymerase chain reaction was performed on genes >10-fold upregulated in ZG (compared with zona fasciculata) and >10-fold upregulated in aldosterone-producing adenomas (compared with ZG). DACH1, a gene associated with tumor progression, was further analyzed. The role of DACH1 on steroidogenesis, transforming growth factor-β, and Wnt signaling activity was assessed in the human adrenocortical cell line, H295R. Immunohistochemistry confirmed selective expression of DACH1 in human ZG. Silencing of DACH1 in H295R cells increased CYP11B2 mRNA levels and aldosterone production, whereas overexpression of DACH1 decreased aldosterone production. Overexpression of DACH1 in H295R cells activated the transforming growth factor-β and canonical Wnt signaling pathways but inhibited the noncanonical Wnt signaling pathway. Stimulation of primary human adrenal cells with angiotensin II decreased DACH1 mRNA expression. Interestingly, there was little overlap between our top ZG genes and those in rodent ZG. In conclusion, (1) the transcriptome profile of human ZG differs from rodent ZG, (2) DACH1 inhibits aldosterone secretion in human adrenals, and (3) transforming growth factor-β signaling pathway is activated in DACH1 overexpressed cells and may mediate inhibition of aldosterone secretion in human adrenals. [ABSTRACT FROM AUTHOR]