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Context NOTCH signaling is activated in endometriotic lesions, but the exact mechanisms remains unclear. IL-6, which is increased in the peritoneal fluid of women with endometriosis, induces NOTCH1 through E-proteins including E2A and HEB in cancer. Objective To study the role of E-proteins in inducing NOTCH1 expression under the regulation of IL-6 in endometriosis. Setting and Design The expression of E-proteins and NOTCH1 was first investigated in endometrium of women with endometriosis and the baboon model of endometriosis. Regulation of E-proteins and NOTCH1 expression was examined after IL-6 stimulation and siRNA mediated inhibition of E2A or/and HEB in human endometriotic epithelial cells (12Z) in vitro, and subsequently following IL-6 treatment in the mouse model of endometriosis in vivo. Results E2A, HEB, and NOTCH1 were significantly upregulated in glandular epithelium (GE) of ectopic endometrium compared to eutopic endometrium in both women and the baboon model. IL-6 treatment upregulated the expression of NOTCH1 together with E2A and HEB in 12Z cells. Small interfering RNA inhibition of E2A and HEB or HEB alone decreased NOTCH1 expression. Binding efficiency of both E2A and HEB was significantly higher at the binding sites on the human NOTCH1 promoter after IL-6 treatment. Finally, IL-6 treatment resulted in a significantly increased number of endometriotic lesions along with increased expression of E2A, HEB, and NOTCH1 in GE of the lesions compared with the vehicle group in an endometriosis mouse model. Conclusions IL-6 induced NOTCH1 expression is mediated by E-proteins in the ectopic GE cells, which may promote endometriotic lesion development.

Although a benign gynecological disorder, endometriosis displays some pathogenic features of malignancy, such as cell proliferation, migration, invasion, and adaptation to hypoxia. Current treatments of endometriosis include pharmacotherapy and/or surgery, which are of limited efficacy and often associated with adverse side-effects. Therefore, to develop more effective therapies to treat this disease, a broader understanding of the underlying molecular mechanisms that underpin endometriosis needs to be attained. Using immortalized human endometriotic epithelial and stromal cell lines, we demonstrate that the early growth response 1 (EGR1) transcription factor is essential for cell proliferation, migration and invasion, which represent some of the pathogenic properties of endometriotic cells. Genome-wide transcriptomics identified an EGR1-dependent transcriptome in human endometriotic epithelial cells that potentially encodes a diverse spectrum of proteins that are known to be involved in tissue pathologies. To underscore the utility of this transcriptomic dataset, we demonstrate that carbonic anhydrase IX (CAIX), a homeostatic regulator of intracellular pH, is not only a molecular target of EGR1 but is important for maintaining many of the cellular properties of human endometriotic epithelial cells that are also ascribed to EGR1. Considering therapeutic intervention strategies are actively being developed for EGR1 and CAIX in the treatment of other pathologies, we believe EGR1 and its transcriptome (which includes CAIX) will offer not only a new conceptual framework to advance our understanding of endometriosis but will furnish new molecular vulnerabilities to be leveraged as potential therapeutic options in the future treatment of endometriosis.

ARID1A and PI3-Kinase (PI3K) pathway alterations are common in neoplasms originating from the uterine endometrium. Here we show that monoallelic loss of ARID1A in the mouse endometrial epithelium is sufficient for vaginal bleeding when combined with PI3K activation. Sorted mutant epithelial cells display gene expression and promoter chromatin signatures associated with epithelial-to-mesenchymal transition (EMT). We further show that ARID1A is bound to promoters with open chromatin, but ARID1A loss leads to increased promoter chromatin accessibility and the expression of EMT genes. PI3K activation partially rescues the mesenchymal phenotypes driven by ARID1A loss through antagonism of ARID1A target gene expression, resulting in partial EMT and invasion. We propose that ARID1A normally maintains endometrial epithelial cell identity by repressing mesenchymal cell fates, and that coexistent ARID1A and PI3K mutations promote epithelial transdifferentiation and collective invasion. Broadly, our findings support a role for collective epithelial invasion in the spread of abnormal endometrial tissue., PIK3CA mutations and ARID1A loss co-exist in endometrial neoplasms. Here, the authors show that these co-mutations drive gene expression profiles correlated with differential chromatin accessibility and ARID1A binding in the endometrial epithelium, resulting in partial EMT and myometrial invasion.

About 40% of women with infertility and 70% of women with pelvic pain suffer from endometriosis. The pregnancy rate in women undergoing IVF with low endometrial integrin αvβ3 (LEI) expression is significantly lower compared to the women with high endometrial integrin αvβ3 (HEI). Mid-secretory eutopic endometrial biopsies were obtained from healthy controls (C; n=3), and women with HEI (n=4) and LEI (n=4) and endometriosis. Changes in gene expression were assessed using human gene arrays and DNA methylation data were derived using 385 K Two-Array Promoter Arrays. Transcriptional analysis revealed that LEI and C groups clustered separately with 396 differentially expressed genes (DEGs) (P

The present study was undertaken to assess the degree of oxidative stress and toxic effects induced by chromium on hepatic tissue in male Wistar rats exposed to a realistic dosage of Cr(VI) (20 mg/kg/b.w./day) through drinking water, based on the levels of these metals found in the environment, for a duration of 15, 30 and 60 days. The protective effect of melatonin (10 mg/kg) was also studied by simultaneous administration with the metal. Levels of enzymatic and non-enzymatic antioxidants as well as lipid peroxidation were assessed. There was a significant decrease in enzymatic as well as non-enzymatic antioxidants and an increase in the lipid peroxidation level, which were prevented and maintained at near-normal levels by the administration of melatonin in all treatment periods. Metal accumulation was maximal at 15 days, with gradual decreases till 60 days. Histopathological observations also demonstrated the fact that Cr (VI) exposure leads to cytological lesions in the hepatic tissue promoting cellular necrotic/apoptotic changes, while melatonin was able to counteract insults induced by Cr (VI) at all treatment periods. It also prevented alterations in insulin and glucose levels. Overall, the present study suggests a duration-dependent effect of Cr on hepatic oxidative stress and cytotoxicity and shows the potent activity of melatonin in preventing the negative effects of Cr (VI).

An important step toward successful pregnancy involves invasion of the trophoblast cells into the decidua for placentation. Herein, we show that in the human and baboon decidua HOXA10 expression is downregulated after implantation and that this reduction is most prominent in the decidual cells juxtaposed to the invading placental villi. The supernatants derived from HOXA10-depleted human decidual cells increase the invasiveness of the trophoblast cell lines ACH-3P and JEG3 in vitro; this increase is due to higher expression and activity of matrix metalloproteases (MMPs) and reduced expression of tissue inhibitors of MMPs in both the cell lines. The proinvasive ability of HOXA10-depleted decidual cells is due to increased levels and secretion of leukemia inhibitor factor (LIF) and interleukin (IL)-6. Both these cytokines individually promote invasion of ACH-3P and JEG3 cell by increasing the activities of MMPs and decreasing mRNA levels of TIMPs. Finally, we demonstrate that the supernatants derived from HOXA10-depleted decidual cell–phosphorylated STAT3 (Tyr 705) and knocking down STAT3 in ACH-3P and JEG3 cells restrained the invasion mediated by supernatants derived from HOXA10-depleted decidual cells. These results imply that STAT3 activity is essential and sufficient to promote invasion in response to downregulation of HOXA10 in decidual cells. We propose that downregulation of HOXA10 in the decidual cells promotes the expression of LIF and IL-6, which, in a paracrine manner, activates STAT3 in the trophoblast cells, leading to an increase in MMPs to facilitate invasion.

Endometrial-like stromal cells, one of the main components of endometriotic lesions, are an important in vitro model for studying cellular and molecular mechanisms associated with lesion development in endometriosis. However, the short life span of primary endometriotic stromal cells (Ec-ESCs) limits their use. Human telomerase reverse transcriptase (hTERT) plasmids can be used to develop immortalized cell lines. Here we aimed to establish an endometriotic stromal cell line by hTERT immortalization. Primary Ec-ESCs were obtained from a human ovarian endometriotic cyst. The purity was assessed by morphology and the expression of vimentin, cytokeratin, and human interferon-inducible transmembrane protein 1 (hIFITM1). Cells were infected with hTERT lentiviral vector and selected with hygromycin. hTERT mRNA levels were confirmed by RT-qPCR. Immortalized Ec-ESCs (iEc-ESCs) were characterized by examining the expression of morphological markers and key genes of interest, TP53, estrogen receptor β (ERβ), progesterone receptor (PR), and steroidogenic factor-1 (SF-1). Karyotyping and in vitro decidualization studies were also performed. Ec-ESCs were positive for vimentin and hIFITM1 and negative for cytokeratin, indicating that they were representative of Ec-ESC. The fibroblast-like morphology, expression of TP53, ERβ, PR, and SF-1 did not change before and after hTERT immortalization. iEc-ESCs showed an impaired decidualization response like primary Ec-ESCs when compared to normal eutopic stromal cells. Karyotyping showed that 15/19 cells had normal female karyotype, while 4/19 cells had partial trisomy 11q. Collectively, we successfully established and characterized an immortalized endometriotic stromal cell line. It is potentially useful as an in vitro experimental model to investigate endometriosis biology.

Endometriosis is a common gynecological disorder defined by the presence of endometrial tissue outside the uterus which affects 10–15% of women and is associated with pelvic pain and infertility. It is an estrogen-dependent, inflammatory disease associated with elevated tissue, peripheral and peritoneal cytokines. The presence of the disease results in aberrant gene expression in the eutopic endometrium, development of progesterone resistance, and impaired decidualization. The molecular mechanisms driving these phenotypic changes in both the eutopic and ectopic endometrium are not clear. Therefore, to study the mechanisms of disease onset and early development, animal models in which the onset of disease can be exactly controlled are necessary. The use of nonhuman primates is advantageous for the study of endometriosis because they are phylogenetically similar to humans. Among all the available nonhuman primate models, the baboon (Papio anubis) is preferred because of its size, similar reproductive anatomy and physiology, and the ability to evaluate disease pathogenesis from the onset of disease induction. This chapter summarizes our findings on how the presence of ectopic lesions influences the eutopic endometrial gene signature leading to altered endometrial function, progesterone resistance, and impaired decidualization. We suggest that the presence of endometriosis leads to rapid and significant changes in the expression of several microRNAs (miRNAs) which in turn may impact the altered gene signature contributing to the pathology of the disease including progesterone resistance. Notch signaling plays a vital role in cell survival, cellular communication, and differentiation throughout development in a variety of species. We document that decreased NOTCH1 signaling in eutopic endometrium compromises decidualization. Additionally, we demonstrate that altered signaling pathways (AKT, MAPK, ERK, and HIF1A-STAT3) along with epigenetic changes further contribute to progesterone resistance and decidualization defects. Thus, inflammation and altered microRNA expression, in both the eutopic and ectopic endometrium, impact the progesterone-regulated gene networks leading to compromised endometrial function as a consequence of endometriosis.

In this Letter, we experimentally demonstrate a terahertz (THz) whispering gallery mode (WGM) sensor based on a sapphire WGM resonator. The fundamental mode at 129.49 GHz with a Q-factor of 4.63 x 10(3) is used to study its sensitivity to adsorbed molecules. The efficiency of our sensor to detect rhodamine 6G dye molecules in a polyvinyl alcohol matrix at room temperature has been manifested, and a detection sensitivity of 25 parts per million has been achieved. Also, we report an analytical approach based on coupled-mode theory between the waveguide mode and the spherical resonator mode to evaluate the absorption coefficient of the adsorbed molecule on the resonator. The model is modified to evaluate optical constants of materials. The results obtained have been verified by continuous-wave THz transmission results. The results are of importance in sensing, metrology, and material characterization. (C) 2018 Optical Society of America

In many repeat diseases, such as Huntington's disease (HD), ongoing repeat expansions in affected tissues contribute to disease onset, progression and severity. Inducing contractions of expanded repeats by exogenous agents is not yet possible. Traditional approaches would target proteins driving repeat mutations. Here we report a compound, naphthyridine-azaquinolone (NA), that specifically binds slipped-CAG DNA intermediates of expansion mutations, a previously unsuspected target. NA efficiently induces repeat contractions in HD patient cells as well as en masse contractions in medium spiny neurons of HD mouse striatum. Contractions are specific for the expanded allele, independently of DNA replication, require transcription across the coding CTG strand and arise by blocking repair of CAG slip-outs. NA-induced contractions depend on active expansions driven by MutSβ. NA injections in HD mouse striatum reduce mutant HTT protein aggregates, a biomarker of HD pathogenesis and severity. Repeat-structure-specific DNA ligands are a novel avenue to contract expanded repeats.

Bismuth selenide (Bi2Se3) thin films of nominal thickness ∼10 nm were grown on (100) SrTiO3 and (100) LaAlO3 single crystal substrates using molecular beam epitaxy and their charge transport properties were investigated in the temperature range of 1.5 K–300 K. Bi2Se3 films deposited on (100) LaAlO3 exhibit semiconducting behavior, while films prepared on (100) SrTiO3 exhibited an anomalous semiconductor-to-metal-like transition at 68 K. The low temperature metal like transition is attributed to compressive strains arising due to structural phase transition of SrTiO3 substrate, which modulate the Bi2Se3 grain boundary width and facilitate the electric field assisted tunneling of charge carrier at the grain boundaries. The field assisted tunneling of charge carriers is supported by the inverse square-root field dependence of electrical conductivity.

INTRODUCTION: More than 50% of high-grade serous ovarian cancers (HGSOC) are deficient in Homologous Recombination (HR) DNA repair, predominantly due to inactivation of BRCA1 or BRCA2 genes. HR-deficient cancers are sensitive to inhibitors of Poly-ADP Ribose Polymerase (PARP), and PARP inhibitors (PARPi's) have shown promising efficacy in the treatment of HGSOC. However, the majority of HGSOC patients will eventually develop resistance to PARPi's, and no overall survival benefit has been reported. Clinically, best characterized mechanism of PARPi resistance is restoration of BRCA1/2 protein expression accounting for 20-50% of clinical cases. Recently, emerging preclinical evidence has emphasized the role of replication fork protection in PARPi resistance. In addition, transcriptional regulation of the DNA damage response (DDR) proteins, including 53BP1, have been shown to contribute to PARPi resistance. However, the lack of understanding on the functional heterogeneity of the different PARP inhibitor resistance mechanisms has hampered the clinical targeting and development of biomarkers for acquired PARPi resistance in HGSOC. RESULTS: To understand the dynamics and origin of PARPi resistance, we generated a TP53-/- and BRCA1-/- deficient epithelial (RPE) cell line using the CRISPR/Cas9 system. These cells are deficient in HR, and therefore are hypersensitive to PARPi in vitro. Using cyclic exposure of increasing concentrations of the PARPi Niraparib, we selected a cell population that were resistant to high concentrations (µM range) of the drug. We next isolated single cell clones from the resistant pool and performed deep functional profiling. As expected, the clones were resistant to multiple PARPi, including Niraparib, Olaparib and Talazoparib, and showed decreased DNA damage after PARPi treatment. However, none of the clones has restored BRCA1 protein expression. In functional assays, some clones had different levels of restored HR, and others showed a predominantly fork-stable, non HR-restored phenotype. Upon cytogenetic analyses, the parental RPETP53-/-BRCA1-/- cells exhibited high clonal heterogeneity in terms of ploidy, whereas the PARPi resistant clones are mostly triploid. Interestingly, the HR-restored clones have lower levels of baseline chromosomal aberrations; however, mitomycin C induced chromosomal breaks in all the clones. In flow cytometry-based cell cycle profiling, the clones retained the G2/M accumulation upon PARPi treatment, similar to the parental RPETP53-/-BRCA1-/- cells. Interestingly, all PARPi resistant clones show decreased levels of the DDR protein KAP1, and divergent expression levels of other DDR proteins, such as 53BP1. Importantly, the clones show significant heterogeneity in terms of sensitivity to cisplatin, as well as to DDR targeting agents, such as inhibitors of ATR and CHK1. CONCLUSIONS: We have engineered BRCA1- deficient cells that are resistant to PARPi, and show that subclones of from these cells have significant functional heterogeneity in DNA repair dynamics, and are differentially vulnerable to DDR targeting agents. Importantly, our model system suggests that acquired PARP inhibitor resistance involves the adoption of several distinct resistance mechanisms that are potentially linked to DDR regulation. To enable clinical translation of our findings, we are in the process of performing genomic and transcriptomic profiling to discover the genomic evolution, common vulnerabilities, and novel biomarkers for acquired PARPi resistance in HGSOC. Citation Format: Anniina Färkkilä, Alfredo Rodriquez, Jaana Olkkonen, Larissa Sambel, Julieta Dominiquez, Niraj Joshi, Connor Clairmont, Jia Zhou, Kah-Suan Lim, Sampsa Hautaniemi, and Alan D'Andrea. FUNCTIONAL HETEROGENEITY OF ACQUIRED PARP INHIBITOR RESISTANCE IN BRCA1-DEFICIENT CELLS [abstract]. In: Proceedings of the 12th Biennial Ovarian Cancer Research Symposium; Sep 13-15, 2018; Seattle, WA. Philadelphia (PA): AACR; Clin Cancer Res 2019;25(22 Suppl):Abstract nr NT-092.

High-grade serous ovarian carcinoma (HGSOC) patients with germline mutations in BRCA1/2 exhibit high sensitivity and improved outcome to double strand DNA break (DSB)-inducing agents [i.e. platinum and Poly(ADP-ribose) polymerase inhibitors (PARPi)] due to underlying defects in DNA repair via homologous recombination (HR). Due to their effectiveness, three PARP inhibitors (olaparib, rucaparib, niraparib) have recently gained FDA approval for the treatment of HGSOCs. However, de novo and acquired resistance to these agents is common even in the BRCA mutation carriers, and pose a significant, and unsolved, clinical challenge. Therefore, we adopted a systematic approach to comprehensibly identify unexplored factors/pathways that could be responsible for PARPi/platinum resistance in BRCA-defective HGSOC patients. Here we identify DYNLL1 as a negative regulator of DNA end resection through a loss-of-function CRISPR screen in BRCA1-mutant ovarian carcinoma cells. DNA end resection is a vital process that initiates homologous recombination (HR)-mediated repair of double-stranded DNA breaks (DSBs), and consequently influences genome stability. In BRCA-defective HGSOC patients, DNA end resection is greatly compromised and contribute to the loss of HR and PARP inhibitor sensitivity. Loss of DYNLL1 allows DNA end resection and restores HR in BRCA1-mutant cells, thereby inducing resistance to platinum drugs and PARP inhibitors. In primary ovarian carcinomas low BRCA1 expression correlates with increased chromosomal aberrations, and the junction sequences of somatic structural variants indicate the loss of HR. Concurrent decrease in DYNLL1 expression in BRCA1 low ovarian cancers ‘rescued' this phenotype with reduced genomic alterations and increased homology at putative lesions. DYNLL1 limits nucleolytic degradation of DNA ends by interacting with the DNA end resection machinery (MRN complex, BLM helicase and DNA2) in cells. The impact of DYNLL1 on end resection can be re-capitulated in vitro and this is dependent on direct interaction with MRE11. In the absence of exogenous stress, depletion of DYNLL1 slows DNA replication fork progression due to ectopic activity of MRE11. Therefore, we infer that DYNLL1 is an important anti-resection factor that significantly influences genomic stability and response to DNA damaging chemotherapy. Citation Format: Yizhou Joseph He, Khyati Meghani, Marie-Christine Caron, Chunyu Yang, Daryl A. Ronato, Jie Bian, Anchal Sharma, Jessica Miller, Niraj Joshi, Alexandre Detappe, John G. Doench, Gaelle Legube, David E. Root, Alan D. D'Andrea, Pascal Drané, Subhojyoti De, Panagiotis Konstantinopoulos, Jean-Yves Masson, and Dipanjan Chowdhury. DYNLL1 INHIBITS DNA END RESECTION IN BRCA1-DEFICIENT CELLS AND REGULATES PARP INHIBITOR SENSITIVITY [abstract]. In: Proceedings of the 12th Biennial Ovarian Cancer Research Symposium; Sep 13-15, 2018; Seattle, WA. Philadelphia (PA): AACR; Clin Cancer Res 2019;25(22 Suppl):Abstract nr GMM-027.

We have previously demonstrated that human microRNA-451a (miR-451a) endometriotic lesion expression is significantly higher compared to that of the corresponding eutopic endometrium. The objective of the current study was to examine the relationship between lesion and serum content of miR-451a and to determine the utility of serum miR-451a in distinguishing between women with and without visible signs of endometriosis. Eighty-one participants were enrolled in this study, 41 with confirmed endometriosis and 40 without visible signs of endometriosis at laparoscopy (n = 20) or symptoms of endometriosis (pain, infertility n = 20). Experimental endometriosis was also induced in 8 baboons. Blood, endometriotic lesions, and eutopic endometrial samples were collected from women undergoing laparoscopy for surgical removal of endometriosis. Blood was also collected from control participants with no signs and symptoms associated with the disease as well as from baboons prior to, and then 1, 3, 6, 9, and 15 months postinduction of endometriosis. MicroRNA-451a was assessed by quantitative real-time polymerase chain reaction in all samples. In humans, serum miR-451a levels positively correlated with endometriotic lesion miR-451a content, and sera levels were significantly higher in these participants compared to controls. The area under the curve (AUC) for miR-451a was 0.8599. In baboons, serum miR-451a reached statistically significant peak levels at 6 months postinduction of endometriosis. We conclude from this study that sera miR-451a levels positively correlated with endometriotic lesion content and are significantly greater compared to sera levels in women without visible signs or symptoms of endometriosis. MicroRNA-451a may serve as a serum diagnostic marker for endometriosis.

Context: Endometriosis results in aberrant gene expression in the eutopic endometrium (EuE) and subsequent progesterone resistance. MicroRNA (miR) microarray data in a baboon model of endometriosis showed an increased expression of miR-29c. Objectives: To explore the role of miR-29c in progesterone resistance in a subset of women with endometriosis. Design: MiR-29c expression was analyzed in the endometrium of baboons and women with or without endometriosis. The role in progesterone resistance and decidualization was analyzed by transfecting human uterine fibroblast cells with miR-29c. Patients: Subjects diagnosed with deep infiltrative endometriosis (DIE) by transvaginal ultrasound with bowel preparation underwent surgical excision of endometriosis. Eutopic secretory endometrium was collected pre- and postoperatively. Women with normal EuE and without DIE served as controls. Results: Quantitative reverse transcription polymerase chain reaction demonstrated that miR-29c expression increased, while the transcript levels of its target, FK506-binding protein 4 (FKBP4), decreased in the EuE of baboons following the induction of endometriosis. FKBP4 messenger RNA and decidual markers were statistically significantly decreased in decidualized human uterine fibroblast cells transfected with a miR-29c mimic compared with controls. Human data corroborated our baboon data and demonstrated higher expression of miR-29c in endometriosis EuE compared with normal EuE. MiR-29c was significantly decreased in endometriosis EuE postoperatively compared with preoperative tissues, and FKBP4 showed an inverse trend following radical laparoscopic resection surgery. Conclusions: We demonstrate that miR-29c expression is increased in EuE of baboons and women with endometriosis, which might contribute to a compromised progesterone response by diminishing the levels of FKBP4. Resection of DIE is likely to reverse the progesterone resistance associated with endometriosis in women.

Present study evaluates cardioprotective role of melatonin (Mel), alpha lipoic acid (ALA), a combination of melatonin and alpha lipoic acid (Mel + ALA) against cadmium (Cd)-induced oxidative damage. Female albino rats were subjected to 15-day exposure to Cd (5.12 mg/kg bw) alone or treated with ML (10 mg/kg bw) + ALA (25 mg/kg bw) simultaneously. Plasma markers of cardiac damage, cardiac free radical generation, lipid peroxidation, endogenous antioxidant status, cadmium load, metallothionein induction, and histopathology were evaluated in various experimental groups. Combination of Mel + ALA significantly prevented leakage of marker enzymes of cardiac damage, changes in cardiac free radical generation, endogenous antioxidants, antioxidant status, structural alterations and augmented the degree of metallothionein (MT) induction. The results demonstrate that ML + ALA co-administration effectively protected against Cd-induced cardiac oxidative damage.

We have investigated the temperature dependent electrical resistivity, ρ ( T ) , of Ag(100 nm)/Al(10 nm) bilayers grown on Si(111) and quartz substrates using molecular beam epitaxy (MBE). Bilayers grown on Si exhibited an anomalous negative temperature coefficient of resistivity (TCR) in the temperature range of 140–165 K of the ρ ( T ) plot. However, at temperatures below and above this negative TCR region, ρ ( T ) exhibited a characteristic positive TCR of metallic alloys. No such resistive anomaly was observed for the bilayers grown on quartz substrates. The observed resistive anomaly could be qualitatively explained by assuming two parallel conduction channels, that is, one at the interface having high Si content and obeying the polaronic behavior at

STUDY QUESTION Are microRNAs (miRs) altered in the eutopic endometrium (EuE) of baboons following the induction of endometriosis? SUMMARY ANSWER Induction of endometriosis causes significant changes in the expression of eight miRs, including miR-451, in the baboon endometrium as early as 3 months following induction of the disease. WHAT IS KNOWN ALREADY Endometriosis is one of the most common gynecological disorders and causes chronic pelvic pain and infertility in women of reproductive age. Altered expression of miRs has been reported in women and has been suggested to play an important role in the pathophysiology of several gynecological disorders including endometriosis. STUDY DESIGN, SIZE, DURATION EuE was obtained from the same group of baboons before and 3 months after the induction of endometriosis. The altered expression of miR-451 was validated in the eutopic and ectopic endometrium of additional baboons between 3 and 15 months following disease induction. Timed endometrial biopsies from women with and without endometriosis were also used to validate the expression of miR-451. PARTICIPANTS/MATERIALS, SETTING, METHODS Total RNA was extracted from EuE samples before and after the induction of endometriosis, and miRNA expression was analyzed using a 8 × 15 K miR microarray. Microarray signal data were preprocessed by AgiMiRna software, and an empirical Bayes model was used to estimate the changes. The present study focused on quantitative RT-PCR validation of the microarray data, specifically on miR-451 and its target genes in both baboons (n = 3) and women [control (n = 7) and endometriosis (n = 19)]. Descriptive and correlative analysis of miR-451 and target gene expression was conducted using in situ hybridization and immunohistochemistry, while functional analysis utilized an in vitro 3' untranslated region (UTR) luciferase assay and overexpression of miR-451 in human endometrial and endometriotic cell lines. MAIN RESULTS AND THE ROLE OF CHANCE Induction of endometriosis results in the altered expression of miR-451, -141, -29c, -21, -424, -19b, -200a and -181a in the baboon endometrium. In the baboon, induction of endometriosis significantly decreased the expression of miR-451 at 3 months (P < 0.001), which was also associated with increased expression of its target gene YWHAZ (14.3.3ζ). A similar significant (P < 0.0001) decrease in miR-451 expression was observed in women with endometriosis. The 3' UTR luciferase assay confirmed the regulation of YWHAZ expression by miR-451. Furthermore, overexpression of miR-451 in 12Z cells (immortalized human endometriotic epithelial cell line) led to the decreased expression of its target YWHAZ and this was correlated with decreased cell proliferation. LIMITATIONS, REASONS FOR CAUTION The study focused only on miR-451 and one of its targets, namely YWHAZ. A single miR could target number of genes and a single gene could also be regulated by number of miRs; hence, it is possible that other miRs and their regulated genes may contribute to the pathophysiology of endometriosis. WIDER IMPLICATIONS OF THE FINDINGS Our data suggest that the presence of ectopic lesions in baboon causes changes in EuE miR expression as early as 3 months postinduction of the disease, and some of these changes may persist throughout the course of the disease. We propose that the marked down-regulation of miR-451 in both baboons and women with endometriosis increases the expression of multiple target genes. Increased expression of one of the target genes, YWHAZ, increases proliferation, likely contributing to the pathophysiology of the disease.

The morphology and electrical resistivity of ultrathin Al metal films grown on (111) Si substrates using molecular-beam epitaxy have been investigated. For thickness

The Ag/Al bilayer-structures consisting of 10 nm Al and 100 nm Ag have been grown on (1 1 1) Si substrates using molecular beam epitaxy (MBE). The bilayer-structures were annealed in situ under a vacuum of 10 −8 Torr at different temperatures between 25 and 800 °C for a fixed period of 30 min and, characterized by in situ X-ray photoelectron spectroscopy (XPS) and ex situ X-ray diffraction (XRD), Atomic force microscopy (AFM) and four-probe dc electrical resistivity measurements. The XPS results revealed that the surface composition of bilayer-structures becomes systematically depleted in Ag and gets enriched in Al and oxygen with increasing annealing temperature. However, at 800 °C the Si also appeared at the surface. The room temperature resistivity value exhibited an unusual dependence on annealing temperature, which is understood in terms of Al induced disorder in Ag. In addition, the temperature dependence of resistivity of bilayer-structures annealed at 500 and 800 °C showed an anomalous metal-to-insulator transition and could be explained using a thermally activated polaron hopping mechanism.

We have grown single crystals of recently discovered thermoelectric oxide material NaxCoO2 using NaCl flux. Crystals of sizes upto 1.5 x 1.5 x 1.5 mm3 having different morphological habits were reproducibly grown. The atomic force microscopic studies show that along c-axis crystals grow via 2D layer-by-layer mechanism. The X-ray diffraction analyses show that grown crystals are rich in Na content as compared to the starting charge indicating that NaCl flux also acts as a source of Na. The resistivity of the crystals exhibited a linear temperature dependence in the region between 30 and 300 K. © 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Nanocrystalline thin films of Pd metal has been deposited using inert gas condensation technique on (1 1 1) oriented Si substrates. The film morphology of Pd films grown under different argon gas pressures has been investigated using atomic force microscope (AFM), in contact mode. The results show that the film morphology depends strongly on argon pressure and the lowest grain size of ∼20 nm is obtained at a pressure of 10 −2 Torr. The films are found to grow with (1 1 1) orientation. X-ray photoelectron spectroscopic studies show that grown films are always metallic.

Tellurium thin films were studied for its use as ammonia gas sensors operable at room temperature. The films showed a reversible increase in resistance when exposed to ammonia and the response was found to be linear in the range of 0–100 ppm. The interaction of ammonia with tellurium film was investigated using Raman, XPS and impedance spectroscopy techniques. The results showed that ammonia reduces tellurium oxide on the surface and grain boundary region of the film to tellurium. This reduces majority carrier density in the film and thereby decreases the conductivity of the film.

To investigate the Al migration in Ag, Ag (100 nm)/Al (10 nm) bilayer structures were grown on (1 1 1) Si substrates using molecular beam epitaxy. The grown bilayers were annealed in situ at different temperatures between 25°C and 500°C (under ∼10 −8 Torr vacuum) and X-ray photoelectron spectra were recorded as a function of annealing time. Even at room temperature, Al was found to migrate to the top of the Ag layer, where it reacted with residual oxygen present in the chamber and formed Al 2 O 3 . The thickness of the so-formed Al 2 O 3 overlayer is found to increase with logarithmic of annealing time. The atomic force microscopic studies show that Al diffusion primarily occurs through grain boundaries.

Angular dependences of resistivity ( ρ ) and critical current density ( J c ) have been measured to determine the effect of pinning at film–substrate and film–air interfaces on dissipation and volume pinning force in c -axis oriented MgB 2 thin films prepared by the ex situ laser ablation technique. It is seen that for the field applied parallel to the ab -plane, interface pinning may reduce resistivity by two orders of magnitude while making nearly same contribution to total pinning force as pinning in bulk of the film. Angular dependence of the upper critical magnetic field ( H c2 ) has been measured and it shows deviations from the anisotropic Ginzburg–Landau model. These deviations have also been understood in terms of the interface pinning effect. The results show that controlled addition of impurities and defects may significantly improve critical current densities in MgB 2 superconductor.

One typical mechanism to promote genomic instability, a hallmark of cancer, is to inactivate tumor suppressors, such as PALB2. It has recently been reported that mutations in PALB2 increase the risk of breast cancer by 8-9 fold. PALB2 was identified BRCA2 interacting protein, essential for BRCA2 anchorage to nuclear structures and for its function in double-strand break repair. Inherited mutations in PALB2 are associated with a predisposition for ovarian, breast and pancreatic cancers. The basis of the tumorigenic potential of PALB2 is thought to be related to functions in homologous recombination. Therefore, the regulation of PALB2 during the DNA damage response and the effect of cancer-causing mutation is of high interest. Two mechanisms of regulation of PALB2 will be presented. The first mechanism regulates PALB2 localization to DNA damage sites in S-phase. To date, predicting the functional consequences of PALB2 mutations has been challenging as they lead to different aggressive phenotypes. Here, we performed a structure-function analysis of PALB2 using PALB2 truncated mutants (R170fs, L531fs, Q775X and W1038X), and uncovered a second PALB2 regulation mechanism by which cancer cells could drive genomic instability. We will present these regulatory mechanisms and synthetic lethal strategies to kill PALB2 deficient cells harbouring such mutations using PARP inhibitors. These strategies also apply to APRIN, A BRCA2 interactor, which also promote double-strand break repair by homologous recombination. Citation Format: Anthony M. Couturier, Rémi Buisson, Joris Pauty, Amélie Rodrigue, Marie-Christine Caron, Yan Coulombe, Niraj Joshi, Lee Zou, Jean-Yves Masson. Mechanisms of regulation and synthetic lethal strategies against PALB2 and APRIN, two DNA double-strand break repair proteins [abstract]. In: Proceedings of the AACR Precision Medicine Series: Opportunities and Challenges of Exploiting Synthetic Lethality in Cancer; Jan 4-7, 2017; San Diego, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2017;16(10 Suppl):Abstract nr B18.

Cancer is a constant threat to humans since one out of three individuals will develop cancer during their lifetime. It has become increasingly clear that tumor formation can be triggered by mutations in enzymes involved in the surveillance of genome integrity, such as BRCA1, BRCA2 and PALB2. BRCA1, BRCA2 and PALB2 are essential players in double–strand break repair by homologous recombination and have been associated with a heightened lifetime risk for ovarian cancer development. Cancer cells with BRCA1/2 and PALB2 deficiency are extremely sensitive to inhibitors of the DNA repair protein PARP, which have recently emerged as promising anti–cancer drugs. However, mutations in BRCA1/2 and PALB2 account only for around 15–20 % of ovarian cancers overall. Developing new strategies to specifically target ovarian cancer is still presenting a major challenge. During homologous recombination, PALB2 links BRCA1 and BRCA2 to promote RAD51 filament formation at DNA double–strand breaks repair. PALB2 interacts directly with BRCA1 via its N–terminal coiled–coil domain and with BRCA2 via its C–terminal WD40 domain. After DNA damage, PALB2–BRCA1 interaction is enhanced to promote PALB2, BRCA2 and RAD51 localization to DNA double–strand breaks. However, how DNA damage promotes the interaction between PALB2 and BRCA1 is still not understood. In this study, we found that the phosphatidylinositol 3–kinase–like proteins kinase ATR is essential to promote PALB2 and RAD51 to DNA double–strand breaks by enhancing the interaction between PALB2 and BRCA1. We identified two functions of ATR important to enhance PALB2–BRCA1 interaction. First, ATR directly phosphorylates PALB2 on serine 59 after DNA damage. Secondly after DNA double–strand breaks resection, ATR down–regulates CDKs activity leading to the decrease of serine 64 phosphorylation on PALB2. Together, these dual events lead to a direct enhancement of the interaction between PALB2 and BRCA1. Furthermore, we generated PALB2 mutants mimicking the active and inactive state of PALB2. We showed that PALB2 phospho–mutants that recapitulated the active state of PALB2 are able to bypass the absence of ATR activity in cells while mutants that mimic the inactive state of PALB2 showed a defect even in presence of active ATR. These results explain for the first time why ATR is essential to promote DNA double–strand break repair by homologous recombination. My results suggest that that ovarian cancer cells that do not carry BRCA1/2 or PALB2 mutations may be rendered “BRCA–like” by treatment with ATR inhibitor, making them susceptible to treatments with PARPi and others DNA damaging drugs. Citation Format: Rémi Buisson, Niraj Joshi, Chu Kwen Ho, Amélie Rodrigue, Tzeh Keong Foo, Emilie Hardy, Wilhelm Haas, Bing Xia, Jean–Yves Masson and Lee Zou. ATR–DEPENDENT REGULATION OF THE OVARIAN CANCER PROTEIN PALB2 AT DNA DOUBLE–STRAND BREAKS [abstract]. In: Proceedings of the 11th Biennial Ovarian Cancer Research Symposium; Sep 12-13, 2016; Seattle, WA. Philadelphia (PA): AACR; Clin Cancer Res 2017;23(11 Suppl):Abstract nr MIP-049.

One typical mechanism to promote genomic instability, a hallmark of cancer, is to inactivate tumor suppressors, such as PALB2. It has recently been reported that mutations in PALB2 increase the risk of breast cancer by 8-9 fold. PALB2 was identified BRCA2 interacting protein, essential for BRCA2 anchorage to nuclear structures and for its function in double-strand break repair. Inherited mutations in PALB2 are associated with a predisposition for ovarian, breast and pancreatic cancers. The basis of the tumorigenic potential of PALB2 is thought to be related to functions in homologous recombination. Therefore, the regulation of PALB2 during the DNA damage response and the effect of cancer-causing mutation is of high interest. Two mechanisms of regulation of PALB2 will be presented. The first mechanism regulates PALB2 localization to DNA damage sites in S-phase through ATR-mediated phosphorylation. We have found specific phosphorylated residues in PALB2 that promote BRCA1-PALB2 interaction after DNA damage. To date, predicting the functional consequences of PALB2 mutations has been challenging as they lead to different aggressive phenotypes. We performed a structure-function analysis of PALB2 using PALB2 truncated mutants (R170fs, L531fs, Q775X and W1038X), and uncovered a second PALB2 regulation mechanism. Our data explains the tumorigenesis associated with some PALB2 mutations, a concept that also applies to other WD40-containing proteins. This abstract is also being presented as Poster B11. Citation Format: Anthony Couturier, Rémi Buisson, Joris Pauty, Amélie Rodrigue, Niraj Joshi, Marie-Christine Caron, Yan Coulombe, Lee Zou, Jean-Yves Masson. Mechanisms of regulation of the tumor suppressor PALB2 [abstract]. In: Proceedings of the AACR Special Conference on DNA Repair: Tumor Development and Therapeutic Response; 2016 Nov 2-5; Montreal, QC, Canada. Philadelphia (PA): AACR; Mol Cancer Res 2017;15(4_Suppl):Abstract nr PR01.

Endometriosis is a common gynecological disease affecting one in 10 women of reproductive age and is a major cause of pelvic pain and impaired fertility. Endometrial stromal cells of women with endometriosis exhibit a reduced response to in vitro decidualization. NOTCH1 is critical for decidualization of both mouse and human uterine stromal cells.This study aimed to determine whether decidualization failure in women with endometriosis is a consequence of impaired Notch signaling.We investigated expression levels of Notch signaling components in the endometrium of women and baboons with or without endometriosis. We identified NOTCH1-regulated genes during decidualization of human uterine fibroblast (HuF) cells by microarray and quantified their expression levels in in vitro-decidualized endometrial stromal cells isolated from women with or without endometriosis.Notch signaling receptors NOTCH1 and NOTCH4, ligands JAGGED2 and DLL4, as well as direct target genes HES5 and HEY1 were decreased in the eutopic endometrium of women and baboons with endometriosis. Notch signaling was decreased in stromal cells isolated from women with endometriosis, which was associated with impaired in vitro decidualization. Genes that were down-regulated by NOTCH1 silencing in decidualized HuF cells were also decreased in decidualized endometrial stromal cells of women with endometriosis. FOXO1 acts as a downstream target of Notch signaling and endometriosis is associated with decreased expression of NOTCH1-regulated, FOXO1-responsive genes during decidualization.Decreased Notch signaling is associated with endometriosis and contributes to impaired decidualization through the down-regulation of FOXO1.

X-ray fluorescent (XRF) spectroscopy has been employed to examine the influence that cationic polysaccharides have on silicone oil deposition onto keratin surfaces (i.e. hair) when delivered from a shampoo under standard washing conditions. The technique offers a rapid method to examine the influence that ancillary shampoo ingredients have on emulsified silicone oil deposition onto a natural fibrous substrate. Using the technique, we have examined the influence that cationic poly(glucose)s and cationic poly(glactomannan)s have on modulating silicone oil deposition. The data suggests that the largest influencing factor in the deposition of the silicone oil resides in the molecular weight of the cationic polymer. Other factors such as polysaccharide composition and cationic charge play lesser roles in the modulation of the oil deposition. However, cationic charge level does appear to influence the nature of the silicone oil deposition after multiple shampooing treatments, providing a controlling influence which appears to prevent build-up of the silicone oil on the keratin fiber.

The octyltrichlorosilane (OTS) monolayer on hydrated Si (111) surfaces has been grafted by cyclic voltammetry (CV) using tetrabutylammonium perchlorate in dry methanol as supporting electrolyte. The percentage of OTS coverage, calculated from the current value at −1V, after 30 CV scans was found to be >97%, which is independently confirmed by atomic force microscopy. A mechanism of electrochemical grafting of OTS on Si via formation of Si–Si bonds is proposed. Current-voltage characteristics and impedance spectroscopic measurements on Al/OTS/Si structures reveal realization of a true OTS/Si interface.

The present study deals with the deposition of hydrogenated amorphous carbon (a-C:H) films on Si (100) substrates with and without an interlayer of nanocrystalline palladium (nc-Pd) on them, by high-voltage electro-dissociation of N,N-dimethyl formamide (DMF). Significant improvement in the sp3 carbon content has been observed for a-C:H films grown on nc-Pd interlayer as revealed by Fourier transformed infrared (FTIR), Raman, X-ray photoelectron spectroscopy (XPS) and photoluminescence (PL) spectroscopic techniques. It is inferred that H2 activation on palladium sites leads to the stabilization of sp3-C bonding, thereby improving the quality of the deposits grown on them., © Elsevier

Thin films of aluminium metal with varying thickness between 10 and 200nm were grown on (I 1 1) Si substrates at 250 degrees C under UHV conditions using molecular beam epitaxy (MBE). Grown thin films were characterized by in situ Xray photoelectron spectroscopy, and ex situ X-ray diffraction, atomic force microscopy and temperature-dependent electrical resisitivity measurements. The results showed that (i) films grow via 3D-island Volmer-Weber growth mechanism, (ii) with increasing film thickness the average grain size increases and the coalescence takes place for thickness > 60 nm, and (iii) independent of the thickness, films grow with (111) orientation. The room-temperature value of resistivity contrary to the predictions of existing theoretical models is found to increase monotonically up to a thickness of 40 nm. This anomalous feature was understood in terms of the film morphology, whereby charge transport takes place via variable range hopping (VRH). For film thickness = 60 mn the resistivity decreased sharply and the M-I transition disappeared. The bulk value of resistivity (2.59 mu Omega cm) was obtained for thickness > 200 urn. (c) 2005

A bimodal magnetic force microscopy technique optimized for lateral resolution and sensitivity for small magnetic stray fields is discussed. A double phase-locked loop (PLL) system is used to drive a high-quality factor cantilever under vacuum conditions on its first mode and simultaneously on its second mode. The higher-stiffness second mode is used to map the topography. The magnetic force is measured with the higher-sensitivity first oscillation mode.

The exchange-bias effect provides unidirectional anisotropy to ferromagnetic thin-films in GMR and TMR sensors. It is weak because it relies on an inherently compensated coupling across a ferromagnet/antiferromagnet interface. We replace the antiferromagnet with a TbFe-based perpendicular-anisotropy amorphous ferrimagnet, coupling to an adjacent ferromagnet with 13-5 mJ/m2 for temperatures within 7.9–280 K. A large exchange-bias between 1.1 and 0.7 T in that temperature range ensues. The temperature dependence of the bias is step-like, and thus different from that of antiferromagnet-based exchange-bias systems. It suggests using this material in exchange-biased temperature assisted magnetic writing.

Magnetic force microscopy (MFM) is able to image and quantify patterns of pinned uncompensated spins (UCS) in exchange-biased samples with high spatial resolution and submonolayer spin sensitivity. However, MFM can only detect magnetic moment distributions with spatial wavelengths within a certain range. Samples with large domains, homogeneous, or divergence-free magnetization fields are not accessible to MFM analysis. In this work we discuss the sample structure constraints placed by the requirement to measure UCS at high spatial resolution, and point out a method to engineer the size of the ferromagnetic domains accordingly.