Chronic exposure of killifish to a highly polluted environment desensitizes estrogen–responsive reproductive and biomarker genes

Reproductive and endocrine disruption is commonly reported in aquatic species exposed to complex contaminant mixtures. We previously reported that Atlantic killifish (Fundulus heteroclitus) from the chronically contaminated Newark Bay, NJ, exhibit multiple endocrine disrupting effects, including inhibition of vitellogenesis (yolk protein synthesis) in females and false negative vitellogenin biomarker responses in males. Here, we characterized the effects on estrogen signaling and the transcriptional regulation of estrogen–responsive genes in this model population. First, a dose–response study tested the hypothesis that reproductive biomarkers (vtg1, vtg2, chg H, chg Hm, chg L) in Newark Bay killifish are relatively less sensitive to 17β–estradiol at the transcriptional level, relative to a reference (Tuckerton, NJ) population. The second study assessed expression for various metabolism (cyp1a, cyp3a30, mdr) and estrogen receptor (ER α, ER βa, ER βb) genes under basal and estrogen treatment conditions in both populations. Hepatic metabolism of 17β–estradiol was also evaluated in vitro as an integrated endpoint for adverse effects on metabolism. In the third study, gene methylation was evaluated for promoters of vtg1 (8 CpGs) and vtg2 (10 CpGs) in both populations, and vtg1 promoter sequences were examined for single nucleotide polymorphism (SNPs). Overall, these studies show that multi–chemical exposures at Newark Bay have desensitized all reproductive biomarkers tested to estrogen. For example, at 10 ng/g 17β–estradiol, inhibition of gene induction ranged from 62% to 97% for all genes tested in the Newark Bay population, relative to induction levels in the reference population. The basis for this recalcitrant phenotype could not be explained by a change in 17β–estradiol metabolism, nuclear estrogen receptor expression, promoter methylation (gene silencing) or SNPs, all of which were unaltered and normal in the Newark Bay population. The decreased transcriptional sensitivity of estrogen–responsive genes is suggestive of a broad effect on estrogen receptor pathway signaling, and provides insight into the mechanisms of the endocrine disrupting effects in the Newark Bay population.Keywords: Killifish, Vitellogenin, Choriogenin, Estrogen, Biomarkers, Endocrine disruptionKeywords: Killifish, Vitellogenin, Choriogenin, Estrogen, Biomarkers, Endocrine disruptio

Antidepressants use during pregnancy and child psychomotor, cognitive and language development at 2 years of age—Results from the 3D Cohort Study

Introduction: Approximately 5.5% of pregnant women take antidepressants. Studies on prenatal exposure to antidepressants reported no association with child cognition, and inconsistent results with motor function and language development. A limitation has been the failure to adjust for prenatal maternal distress.Objectives: Assess the associations between prenatal exposure to antidepressants and child development at age two, while adjusting for maternal depressive symptoms and stress during pregnancy. Explore indirect effects through birth complications and consider sex-specific associations.Methods: This is an ancillary study of the 3D (Design Develop, Discover) Study initiated during pregnancy. Data on antidepressants were collected through medication logs spanning the entire pregnancy. Depressive symptoms and stress were assessed during pregnancy by self-reported questionnaires, motor and cognitive development with the Bayley Scales of Infant and Toddler Development (BSID-III), and language development with the MacArthur Communicative Development Inventories at age 2. Multiple linear regressions were used to assess the associations between exposure and developmental outcomes. Mediation models were used to assess indirect effects. Interaction terms were introduced to assess sex-specific associations.Results: 1,489 mother-child dyads were included, of whom 61 (4.1%) reported prenatal antidepressant use. Prenatal exposure was negatively associated with motor development (B = −0.91, 95% CI -1.73, −0.09 for fine motor, B = −0.89, 95% CI -1.81, 0.02 for gross motor), but not with cognitive (B = −0.53, 95% CI -1.82, 0.72) and language (B = 4.13, 95% CI -3.72, 11.89) development. Adjusting for maternal prenatal distress only slightly modified these associations. No indirect effect or differential effect according to child sex were found.Conclusion: This study supports evidence of a negative association between prenatal exposure to antidepressants and motor development at age two, after adjusting for maternal distress, but the effect size remains very small, with about only one BSID-III point lower in average

Comparative analysis of homology models of the Ah receptor ligand binding domain: Verification of structure-function predictions by site-directed mutagenesis of a nonfunctional receptor

The aryl hydrocarbon receptor (AHR) is a ligand-dependent transcription factor that mediates the biological and toxic effects of a wide variety of structurally diverse chemicals, including the toxic environmental contaminant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). While significant interspecies differences in AHR ligand binding specificity, selectivity, and response have been observed, the structural determinants responsible for those differences have not been determined, and homology models of the AHR ligand-binding domain (LBD) are available for only a few species. Here we describe the development and comparative analysis of homology models of the LBD of 16 AHRs from 12 mammalian and nonmammalian species and identify the specific residues contained within their ligand binding cavities. The ligand-binding cavity of the fish AHR exhibits differences from those of mammalian and avian AHRs, suggesting a slightly different TCDD binding mode. Comparison of the internal cavity in the LBD model of zebrafish (zf) AHR2, which binds TCDD with high affinity, to that of zfAHR1a, which does not bind TCDD, revealed that the latter has a dramatically shortened binding cavity due to the side chains of three residues (Tyr296, Thr386, and His388) that reduce the amount of internal space available to TCDD. Mutagenesis of two of these residues in zfAHR1a to those present in zfAHR2 (Y296H and T386A) restored the ability of zfAHR1a to bind TCDD and to exhibit TCDD-dependent binding to DNA. These results demonstrate the importance of these two amino acids and highlight the predictive potential of comparative analysis of homology models from diverse species. The availability of these AHR LBD homology models will facilitate in-depth comparative studies of AHR ligand binding and ligand-dependent AHR activation and provide a novel avenue for examining species-specific differences in AHR responsiveness. © 2013 American Chemical Society

An adjoint method for the assimilation of statistical characteristics into eddy-resolving ocean models

The study investigates perspectives of the parameter estimation problem with the adjoint method in eddy-resolving models. Sensitivity to initial conditions resulting from the chaotic nature of this type of model limits the direct application of the adjoint method by predictability. Prolonging the period of assimilation is accompanied by the appearance of an increasing number of secondary minima of the cost function that prevents the convergence of this method. In the framework of the Lorenz model it is shown that averaged quantities are suitable for describing invariant properties, and that secondary minima are for this type of data transformed into stochastic deviations. An adjoint method suitable for the assimilation of statistical characteristics of data and applicable on time scales beyond the predictability limit is presented. The approach assumes a greater predictability for averaged quantities. The adjoint to a prognostic model for statistical moments is employed for calculating cost function gradients that ignore the fine structure resulting from secondary minima. Coarse resolution versions of eddy-resolving models are used for this purpose. Identical twin experiments are performed with a quasigeostrophic model to evaluate the performance and limitations of this approach in improving models by estimating parameters. The wind stress curl is estimated from a simulated mean stream function. A very simple parameterization scheme for the assimilation of second-order moments is shown to permit the estimation of gradients that perform efficiently in minimizing cost functions

The cooking task: making a meal of executive functions

Current standardized neuropsychological tests may fail to accurately capture real-world executive deficits. We developed a computer-based Cooking Task (CT) assessment of executive functions and trialed the measure with a normative group before use with a head-injured population. Forty-six participants completed the computerized CT and subtests from standardized neuropsychological tasks, including the Tower and Sorting Tests of executive function from the Delis-Kaplan Executive Function System (D-KEFS) and the Cambridge prospective memory test (CAMPROMPT), in order to examine whether standardized executive function tasks, predicted performance on measurement indices from the CT. Findings showed that verbal comprehension, rule detection and prospective memory contributed to measures of prospective planning accuracy and strategy implementation of the CT. Results also showed that functions necessary for cooking efficacy differ as an effect of task demands (difficulty levels). Performance on rule detection, strategy implementation and flexible thinking executive function measures contributed to accuracy on the CT. These findings raise questions about the functions captured by present standardized tasks particularly at varying levels of difficulty and during dual-task performance. Our preliminary findings also indicate that CT measures can effectively distinguish between executive function and Full Scale IQ abilities. Results of the present study indicate that the CT shows promise as an ecologically valid measure of executive function for future use with a head-injured population and indexes selective executive function’s captured by standardized tests

Olaparib in patients with metastatic castration-resistant prostate cancer with DNA repair gene aberrations (TOPARP-B): a multicentre, open-label, randomised, phase 2 trial

Background Metastatic castration-resistant prostate cancer is enriched in DNA damage response (DDR) gene aberrations. The TOPARP-B trial aims to prospectively validate the association between DDR gene aberrations and response to olaparib in metastatic castration-resistant prostate cancer. Methods In this open-label, investigator-initiated, randomised phase 2 trial following a selection (or pick-the-winner) design, we recruited participants from 17 UK hospitals. Men aged 18 years or older with progressing metastatic castration-resistant prostate cancer previously treated with one or two taxane chemotherapy regimens and with an Eastern Cooperative Oncology Group performance status of 2 or less had tumour biopsies tested with targeted sequencing. Patients with DDR gene aberrations were randomly assigned (1:1) by a computer-generated minimisation method, with balancing for circulating tumour cell count at screening, to receive 400 mg or 300 mg olaparib twice daily, given continuously in 4-week cycles until disease progression or unacceptable toxicity. Neither participants nor investigators were masked to dose allocation. The primary endpoint of confirmed response was defined as a composite of all patients presenting with any of the following outcomes: radiological objective response (as assessed by Response Evaluation Criteria in Solid Tumors 1.1), a decrease in prostate-specific antigen (PSA) of 50% or more (PSA50) from baseline, or conversion of circulating tumour cell count (from ≥5 cells per 7·5 mL blood at baseline to <5 cells per 7·5 mL blood). A confirmed response in a consecutive assessment after at least 4 weeks was required for each component. The primary analysis was done in the evaluable population. If at least 19 (43%) of 44 evaluable patients in a dose cohort responded, then the dose cohort would be considered successful. Safety was assessed in all patients who received at least one dose of olaparib. This trial is registered at ClinicalTrials.gov, NCT01682772. Recruitment for the trial has completed and follow-up is ongoing. Findings 711 patients consented for targeted screening between April 1, 2015, and Aug 30, 2018. 161 patients had DDR gene aberrations, 98 of whom were randomly assigned and treated (49 patients for each olaparib dose), with 92 evaluable for the primary endpoint (46 patients for each olaparib dose). Median follow-up was 24·8 months (IQR 16·7–35·9). Confirmed composite response was achieved in 25 (54·3%; 95% CI 39·0–69·1) of 46 evaluable patients in the 400 mg cohort, and 18 (39·1%; 25·1–54·6) of 46 evaluable patients in the 300 mg cohort. Radiological response was achieved in eight (24·2%; 11·1–42·3) of 33 evaluable patients in the 400 mg cohort and six (16·2%; 6·2–32·0) of 37 in the 300 mg cohort; PSA50 response was achieved in 17 (37·0%; 23·2–52·5) of 46 and 13 (30·2%; 17·2–46·1) of 43; and circulating tumour cell count conversion was achieved in 15 (53·6%; 33·9–72·5) of 28 and 13 (48·1%; 28·7–68·1) of 27. The most common grade 3–4 adverse event in both cohorts was anaemia (15 [31%] of 49 patients in the 300 mg cohort and 18 [37%] of 49 in the 400 mg cohort). 19 serious adverse reactions were reported in 13 patients. One death possibly related to treatment (myocardial infarction) occurred after 11 days of treatment in the 300 mg cohort. Interpretation Olaparib has antitumour activity against metastatic castration-resistant prostate cancer with DDR gene aberrations, supporting the implementation of genomic stratification of metastatic castration-resistant prostate cancer in clinical practice

Chronic PFOS exposures induce life stage-specific behavioral deficits in adult zebrafish and produce malformations in F1 offspring

Perfluorooctanesulphonicacid (PFOS) is an organic contaminant that is ubiquitous in the environment, wildlife, and humans. Few studies have assessed the effects of chronic PFOS exposure on central nervous system function in aquatic organisms. The present study defined the behavioral effects of varying life span chronic exposures to low dose PFOS in zebrafish. The zebrafish were treated with vehicle control or 0.5μM PFOS during 1-21, 21-120, or 1-120 day post fertilization (dpf). Chronic PFOS exposure impaired the adult zebrafish behavior mode under the tapping stimulus. The movement speed of 1-120 dpf exposed fish was significantly increased compared with control, while 1-21 and 21-120 dpf exposed groups were not severely affected. PFOS residues in F1 embryos derived from parental exposure during both the 1-120 and 21-120 dpf groups was significantly higher than control, and F1 embryos in these two groups showed obvious malformations, such as uninflated swim bladder (USB) and bent spine (BS). Larvae of the parental exposed to PFOS from 1-21 or 21-120 dpf elicited a higher swim rate than control in both the light and dark periods. Embryos derived from the 1-120 dpf group showed a statistically lower speed in the light period and a higher speed in the dark period as compared with control. Though there is little PFOS residue in 1-21 dpf group, the adverse behavioral effects on both adult and F1 larvae indicate that exposure during the first 21 dpf induce long-term neurobehavior toxicity. Our findings demonstrate that chronic exposure to low dose PFOS in different life stage adversely impacts adult behavior, subsequent offspring malformation, and larval behavior.This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Society of Environmental Toxicology and Chemistry and can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291552-8618.,Additional authors (Liu, Xiaojuan and Zhu, Guonian) appear and the author order is revised on the published version of this article.Keywords: perfluorooctanesulfonic acid, zebrafish embryo, chronic exposure, behavio

The Wnt pathway regulator DKK1 is preferentially expressed in hormone-resistant breast tumours and in some common cancer types

In addition to new tumour antigens, new prognostic and diagnostic markers are needed for common cancers. In this study, we report the expression of Dickkopf-1 (DKK1) in multiple common cancers. This constitutes a comprehensive analysis of the DKK1 expression profile. Dickkopf-1 expression was evaluated by classical and quantitative reverse transcriptase–polymerase chain reaction (RT–PCR) and enzyme-linked immunosorbant assay for protein determination, in cancer lines and clinical specimens of several cancer origins. For breast cancer, expression was correlated with clinicopathological parameters. Dickkopf-1 expression was confirmed in several cancer cell lines derived from breast and other common cancers. Dickkopf-1 protein secretion was documented in breast, prostate and lung cancer lines, but was negligible in melanoma. Analysis of DKK1 expression in human cancer specimens revealed DKK1 expression in breast (21 out of 73), lung (11 out of 23) and kidney cancers (six out of 20). Interestingly, DKK1 was preferentially expressed in oestrogen and progesterone receptor-negative tumours (ER−/PR−; P=0.005) and in tumours from women with a family history of breast cancer (P=0.024). Importantly, DKK1 protein production was confirmed in multiple breast cancer specimens that were positive by RT–PCR. This work establishes DKK1 as a potential prognostic and diagnostic marker for cohorts of breast cancer patients with poor prognosis. Dickkopf-1 may also become a relevant candidate target for immunotherapy of different cancers

Relationship between initial PSA density with future PSA kinetics and repeat biopsies in men with prostate cancer on active surveillance

The objective of our study is to examine the correlation between PSA density (PSAd) at the time of diagnosis with PSA velocity (PSAV), PSA doubling time and tumour progression, on repeat biopsy, in men with prostate cancer on active surveillance. Data from 102 patients with clinically localized prostate cancer on active surveillance in the period between 1992 and 2007, who had the necessary parameters available, were collected. PSAd was calculated and correlated with PSAV, PSA doubling time (PSADT), Gleason score at diagnosis and local progression on repeated biopsies. PSAV was 0.64 and 1.31 ng ml–1 per year (P=0.02), PSADT of 192 and 113 months (P=0.4) for PSAd below and above 0.15, respectively. The rate of detecting high Gleason score (⩾7) at diagnosis was 6 and 23% for PSAd below and above 0.15, respectively. A total of 101 patients underwent at least a second biopsy and the incidence of upgrading was 10 and 31% for PSAd below and above 0.15, respectively (P=0.001). Although low PSAd is an accepted measure for suggesting insignificant prostate cancer, our study expands its role to indicate that PSAd <0.15 may be an additional clinical parameter that may suggest indolent disease, as measured by future PSAV and repeat biopsy over time