47 research outputs found

    IKKβ targeting reduces KRAS-induced lung cancer angiogenesis in vitro and in vivo: A potential anti-angiogenic therapeutic target

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    Objectives: The ability of tumor cells to drive angiogenesis is an important cancer hallmark that positively correlates with metastatic potential and poor prognosis. Therefore, targeting angiogenesis is a rational therapeutic approach and dissecting proangiogenic pathways is important, particularly for malignancies driven by oncogenic KRAS, which are widespread and lack effective targeted therapies. Based on published studies showing that oncogenic RAS promotes angiogenesis by upregulating the proangiogenic NF-κB target genes IL-8 and VEGF, that NF-κB activation by KRAS requires the IKKβ kinase, and that targeting IKKβ reduces KRAS-induced lung tumor growth in vivo, but has limited effects on cell growth in vitro, we hypothesized that IKKβ targeting would reduce lung tumor growth by inhibiting KRAS-induced angiogenesis. Materials and methods: To test this hypothesis, we targeted IKKβ in KRAS-mutant lung cancer cell lines either by siRNA-mediated transfection or by treatment with Compound A (CmpdA), a highly specific IKKβ inhibitor, and used in vitro and in vivo assays to evaluate angiogenesis. Results and conclusions: Both pharmacological and siRNA-mediated IKKβ targeting in lung cells reduced expression and secretion of NF-κB-regulated proangiogenic factors IL-8 and VEGF. Moreover, conditioned media from IKKβ-targeted lung cells reduced human umbilical vein endothelial cell (HUVEC) migration, invasion and tube formation in vitro. Furthermore, siRNA-mediated IKKβ inhibition reduced xenograft tumor growth and vascularity in vivo. Finally, IKKβ inhibition also affects endothelial cell function in a cancer-independent manner, as IKKβ inhibition reduced pathological retinal angiogenesis in a mouse model of oxygen-induced retinopathy. Taken together, these results provide a novel mechanistic understanding of how the IKKβ pathway affects human lung tumorigenesis, indicating that IKKβ promotes KRAS-induced angiogenesis both by cancer cell-intrinsic and cancer cell-independent mechanisms, which strongly suggests IKKβ inhibition as a promising antiangiogenic approach to be explored for KRAS-induced lung cancer therapy

    Identification of a targetable KRAS-mutant epithelial population in non-small cell lung cancer

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    Lung cancer is the leading cause of cancer deaths. Tumor heterogeneity, which hampers development of targeted therapies, was herein deconvoluted via single cell RNA sequencingin aggressive human adenocarcinomas (carrying Kras-mutations) and comparable murine model. We identified a tumor-specific, mutant-KRAS-associated subpopulation which is conserved in both human and murine lung cancer. We previously reported a key role for the oncogene BMI-1 in adenocarcinomas. We therefore investigated the effects of in vivo PTC596 treatment, which affects BMI-1 activity, in our murine model. Post-treatment, MRI analysis showed decreased tumor size, while single cell transcriptomics concomitantly detected near complete ablation of the mutant-KRAS-associated subpopulation, signifying the presence of a pharmacologically targetable, tumor-associated subpopulation. Our findings therefore hold promise for the development of a targeted therapy for KRAS-mutant adenocarcinomas

    CuO/CeO2 supported on zirconium doped SBA-15 for the Preferential Oxidation of CO

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    Abstract not availableElizabeth A. Law, Erik Meijaard, Brett A. Bryan, Thilak Mallawaarachchi, Lian Pin Koh, Kerrie A. Wilso

    Fluorescence imaging of biochemical relationship between ubiquitinated histone 2A and Polycomb complex protein BMI1

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    Several in vitro experiments have highlighted that the Polycomb group protein BMI1 plays a pivotal role in determining the biological functions of the Polycomb Repressor Complex 1 (PRC1), including its E3-ligase activity towards the Lys119 of histone H2A to yield ubiquitinated uH2A. The role of BMI1 in the epigenetic activity of PRC1 is particularly relevant in several cancers, particularly Non-Small Cell Lung Cancer (NSCLC). In this study, using indirect immunofluorescence protocols implemented on a confocal microscopy apparatus, we investigated the relationship between BMI1 and uH2A at different resolutions, in cultured (A549) and clinical NSCLC tissues, at the single cell level. In both cases, we observed a linear dependence of uH2A concentration upon BMI1 expression at the single nucleus level, indicating that the association of BMI1 to PRC1, which is needed for E3-ligase activity, occurs linearly in the physiological BMI1 concentration range. Additionally, in the NSCLC cell line model, a minor pool of uH2A may exist in absence of concurrent BMI1 expression, indicating non-exclusive, although predominant, role of BMI1 in the amplification of the E3-ligase activity of PRC1. A pharmacological downregulator of BMI1, PTC-209, was also tested in this context. Finally, the absence of significant colocalization (as measured by the Pearson's coefficient) between BMI1 and uH2A submicron clusters hints to a dynamic model where PRC1 resides transiently at ubiquitination sites. Beside unveiling subtle functional relationships between BMI1 and uH2A, these results also validate the use of uH2A as downstream "reporter" for BMI1 activity at the nuclear level in NSCLC contexts

    Six-year outcome for children with ODD or CD treated with the coping power program

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    : Children with severe aggressive behavioral problems are one of the groups most frequently referred to mental health clinics, and they engage in behaviors that put them at risk for substance use problems and a host of other negative outcomes. The present study aimed to assess the long-term outcome (six-year follow up) of the Coping Power Program delivered in a mental health hospital for children with behavioral disorders. We recruited one hundred and twenty children (mean age = 9.9, SD = 0.85), twenty-three patients were lost during the follow-ups. The sample of the current study included sixty-seven youths with Oppositional Defiant Disorder, and thirty with Conduct Disorder. We used Child Behavior Check List, Inventory of Callous Unemotional traits and a youth survey to evaluate substance use. After the baseline evaluation they were allocated to Coping Power or to a generic multi-component treatment. Coping Power produced significant reduction in Callous Unemotional traits, relative to the control condition; Coping Power seems to be effective also in reducing the rate of substance use. However, no differences have been found in externalizing behavior reduction in the two groups. This study contributes to the successful dissemination of best-practice treatments in public mental health services for children

    Origins and evaluation of youth narcissism

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    Recently, studies have focused on narcissism as a personality trait, which can be detected during childhood, and can lead to negative outcomes, such as emotional and behavioral problems. After illustrating the main hypotheses on the development of narcissistic traits in children, this paper aims to outline the relation between narcissism, self-esteem and emotional, and behavioral problems in children. Finally, are presented measures for the assessment of narcissistic traits in children and adolescents

    Parenting practices moderate the link between attention to the eyes and callous unemotional traits in children with Disruptive Behavior Disorder: An eye-tracking study

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    Callous-unemotional (CU) traits are associated with gaze pattern deficits in youths, though it has not yet been explored if environmental factors could influence this relationship. Since parenting can influence both CU traits and children's emotion processing, the current study sought to test whether parenting moderated the relation between gaze pattern deficits and CU traits in a sample of children with Disruptive Behavior Disorder. The sample included 92 boys (aged 7–12 years) with Conduct Disorder (N = 12) and Oppositional Defiant Disorder (N = 80). All children completed a task, during which they were presented with 24 images depicting happy, sad, fearful, disgusted, angry, and neutral facial expressions. Gaze pattern has been recorded throughout the task with an eye-tracker. Positive parenting moderated the association between CU traits and first fixation duration to the eyes of facial expressions depicting negative emotions. Negative parenting moderated the association between CU traits and fixation count and fixation duration to the eyes of negative emotions. Negative parenting along with reduced attention to emotional cues (i.e., eyes) may identify a group of youths with Disruptive Behavior Disorder diagnosis at risk for severe outcomes
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