11 research outputs found

    Claudin-1 regulates cellular transformation and metastatic behavior in colon cancer

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    Disruption of the cell-cell junction with concomitant changes in the expression of junctional proteins is a hallmark of cancer cell invasion and metastasis. The role of adherent junction proteins has been studied extensively in cancer, but the roles of tight junction (TJ) proteins are less well understood. Claudins are recently identified members of the tetraspanin family of proteins, which are integral to the structure and function of TJs. Recent studies show changes in expression/cellular localization of claudins during tumorigenesis; however, a causal relationship between claudin expression/localization and cancer has not been established. Here, we report an increased expression of claudin-1 in human primary colon carcinoma and metastasis and in cell lines derived from primary and metastatic tumors. We also report frequent nuclear localization of claudin-1 in these samples. Genetic manipulations of claudin-1 expression in colon cancer cell lines induced changes in cellular phenotype, with structural and functional changes in markers of epithelial-mesenchymal transition. Furthermore, we demonstrate that changes in claudin-1 expression have significant effects on growth of xenografted tumors and metastasis in athymic mice. We further provide data suggesting that the regulation of E-cadherin expression and β-catenin/Tcf signaling is a possible mechanism underlying claudin-1–dependent changes

    Race/Ethnicity and Gender Representation in Hematology and Oncology Editorial Boards : What is the State of Diversity?

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    Introduction: Women and underrepresented groups in medicine hold few academic leadership positions in the field of hematology/oncology. In this study, we assessed gender and race/ethnicity representation in editorial board positions in hematology/oncology journals. Materials and Methods: Editorial leadership board members from 60 major journals in hematology and oncology were reviewed; 54 journals were included in the final analysis. Gender and race/ethnicity were determined based on publicly available data for Editor-in-Chief (EiC) and Second-in-Command (SiC) (including deputy, senior, or associate editors). Descriptive statistics and chi-squared were estimated. In the second phase of the study, editors were emailed a 4-item survey to self-identify their demographics. Results: Out of 793 editorial board members, 72.6% were men and 27.4% were women. Editorial leadership were non-Hispanic white (71.1%) with Asian editorial board members representing the second largest majority at 22.5%. Women comprised only 15.9% of the EiC positions (90% White and 10% Asian). Women were about half as likely to be in the EiC position compared with men [pOR 0.47 (95% CI, 0.23-0.95, P =. 03)]. Women represented 28.3% of SiC editorial positions. Surgical oncology had the lowest female representation at 2.3%. Conclusion: Women and minorities are significantly underrepresented in leadership roles on Editorial Boards in hematology/oncology journals. Importantly, the representation of minority women physicians in EiC positions is at an inexorable zero

    Abstract 2963: Loss of Smad4 within the intestinal tract results in altered intestinal homeostasis and tumor development

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    Abstract Background: Inactivation of the TGF-β signaling occurs in 50-75% of all colorectal cancer cases. Down-regulation of Smad4, the central mediator of TGF-β signaling, occurs in &amp;gt;50% of stage III patients. How Smad4 contributes to normal intestinal homeostasis and functions as a tumor suppressor are incompletely understood. We reported that β-catenin mRNA expression is inhibited by BMP-mediated Smad4 signaling, and loss of Smad4 signaling results in biologically significant amplification of the Wnt/β-catenin signal. Here, we report on the consequences of Smad4 loss for intestinal homeostasis. Methods: We generated mice genetically engineered to undergo inducible, tissue-specific deletion of Smad4 within intestinal epithelial cells. K19-CreERT x Smad4 flx/flx and Lrig1-CreERT x Smad4 flx/flx mice were treated with vehicle or tamoxifen to induce recombination at the Smad4 locus in the intestinal stem cell compartment. Intestines from sacrificed mice were cleansed for enteroid isolation, Ussing chamber studies, RNA-seq analysis and preservation by formalin fixation and paraffin embedding (FFPE). We validated Smad4 status via immunohistochemistry and stained FFPE sections for different cell populations within the crypt. To evaluate inflammatory cytokines, we performed Luminex cytokine array analysis on colonic mucosa from control and tamoxifen treated animals. To determine the role for Smad4 in intestinal response to injury, we also treated control and tamoxifen treated animals with dextran sodium sulfate (DSS). We utilized RNA-Seq analysis to determine an intestinal Smad4 loss gene signature. Results: Smad4 deficient crypts exhibited an expansion of the Ki67 positive cells in the proliferative zone and fewer Carbonic anhydrase II staining cells suggesting fewer mature enterocytes. We found that loss of Smad4 in the intestinal crypt is accompanied by an accumulation of pericryptal CD3+ lymphocytes and F4/80+ macrophages and is associated with increased intestinal permeability as measured by low molecular weight FITC Dextran using the Ussing chamber. Cytokine analysis revealed Macrophage Inflammatory Protein 3a (MIP3a) to be up-regulated in Smad4 knockout mice. Guided by our RNA-Seq analysis, we observe increased levels of pErk in Smad4 deplete tissue. We also observed that mice with intestinal epithelial Smad4 depletion developed advanced mucinous adenocarcinoma after recovery from an inflammatory stimulus induced by DSS. Conclusions: These results suggest that Smad4 loss disrupts intestinal homeostasis by enabling persistently high levels of Erk signaling to interfere with cell maturation, thereby contributing to increased inflammation. We postulate that the increased inflammation observed in Smad4 knockout mice leads to a tumorigenic environment. Citation Format: Tanner J. Freeman, Jillian Pope, Josh Smith, Daniel Sharbel, Kay Washington, Xi Chen, Rupesh Chaturvedi, Keith Wilson, Noah Shroyer, Punita Dhawan, Anna Means, Natasha G. Deane, R. Daniel Beauchamp. Loss of Smad4 within the intestinal tract results in altered intestinal homeostasis and tumor development. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2963. doi:10.1158/1538-7445.AM2014-2963</jats:p

    Documenting Social Media Engagement as Scholarship: A New Model for Assessing Academic Accomplishment for the Health Professions.

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    BACKGROUND The traditional model of promotion and tenure in the health professions relies heavily on formal scholarship through teaching, research, and service. Institutions consider how much weight to give activities in each of these areas and determine a threshold for advancement. With the emergence of social media, scholars can engage wider audiences in creative ways and have a broader impact. Conventional metrics like the h-index do not account for social media impact. Social media engagement is poorly represented in most curricula vitae (CV) and therefore is undervalued in promotion and tenure reviews. OBJECTIVE The objective was to develop crowdsourced guidelines for documenting social media scholarship. These guidelines aimed to provide a structure for documenting a scholar's general impact on social media, as well as methods of documenting individual social media contributions exemplifying innovation, education, mentorship, advocacy, and dissemination. METHODS To create unifying guidelines, we created a crowdsourced process that capitalized on the strengths of social media and generated a case example of successful use of the medium for academic collaboration. The primary author created a draft of the guidelines and then sought input from users on Twitter via a publicly accessible Google Document. There was no limitation on who could provide input and the work was done in a democratic, collaborative fashion. Contributors edited the draft over a period of 1 week (September 12-18, 2020). The primary and secondary authors then revised the draft to make it more concise. The guidelines and manuscript were then distributed to the contributors for edits and adopted by the group. All contributors were given the opportunity to serve as coauthors on the publication and were told upfront that authorship would depend on whether they were able to document the ways in which they met the 4 International Committee of Medical Journal Editors authorship criteria. RESULTS We developed 2 sets of guidelines: Guidelines for Listing All Social Media Scholarship Under Public Scholarship (in Research/Scholarship Section of CV) and Guidelines for Listing Social Media Scholarship Under Research, Teaching, and Service Sections of CV. Institutions can choose which set fits their existing CV format. CONCLUSIONS With more uniformity, scholars can better represent the full scope and impact of their work. These guidelines are not intended to dictate how individual institutions should weigh social media contributions within promotion and tenure cases. Instead, by providing an initial set of guidelines, we hope to provide scholars and their institutions with a common format and language to document social media scholarship

    Smad4-Mediated Signaling Inhibits Intestinal Neoplasia by Inhibiting Expression of β-Catenin

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    BACKGROUND & AIMS: Mutational inactivation of APC is an early event in colorectal cancer (CRC) progression that affects the stability and increases the activity of β-catenin, a mediator of Wnt signaling. CRC progression also involves inactivation of signaling via transforming growth factor (TGF)β and bone morphenogenic protein (BMP), which are tumor suppressors. However, the interactions between these pathways are not clear. We investigated the effects of loss of the transcription factor Smad4 loss on levels of β-catenin mRNA and Wnt signaling. METHODS: We used microarray analysis to associate levels of Smad4 and β-catenin mRNA in colorectal tumor samples from 250 patients. We performed oligonucleotide-mediated knockdown of Smad4 in human embryonic kidney (HEK293T) and in HCT116 colon cancer cells and transgenically expressed Smad4 in SW480 colon cancer cells. We analyzed adenomas from (APC(Δ1638/+)) and (APC(Δ1638/+))x(K19Cre(ERT2)Smad4(lox/lox)) mice using laser-capture microdissection. RESULTS: In human CRC samples, reduced levels of Smad4 correlated with increased levels of β-catenin mRNA. In Smad4-depleted cell lines, levels of β-catenin mRNA and Wnt signaling increased. Inhibition of BMP or depletion of Smad4 in HEK293T cells increased binding of RNA polymerase II to the β-catenin gene. Expression of Smad4 in SW480 cells reduced Wnt signaling and levels of β-catenin mRNA. In mice with heterozygous disruption of Apc(APC(Δ1638/+)), Smad4-deficient intestinal adenomas had increased levels of β-catenin mRNA and expression of Wnt target genes, compared with adenomas from APC(Δ1638/+)mice that expressed Smad4. CONCLUSIONS: Transcription of β-catenin is inhibited by BMP signaling to Smad4. These findings provide important information about the interaction among TGF-β, BMP, and Wnt signaling pathways in CRC progression

    Addressing liver disease in the UK: a blueprint for attaining excellence in health care and reducing premature mortality from lifestyle issues of excess consumption of alcohol, obesity, and viral hepatitis.

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    Liver disease in the UK stands out as the one glaring exception to the vast improvements made during the past 30 years in health and life expectancy for chronic disorders such as stroke, heart disease, and many cancers. Mortality rates have increased 400% since 1970, and in people younger than 65 years have risen by almost fi ve-times. Liver disease constitutes the third commonest cause of premature death in the UK and the rate of increase of liver disease is substantially higher in the UK than other countries in western Europe. More than 1 million admissions to hospital per year are the result of alcohol-related disorders, and both the number of admissions and the increase in mortality closely parallel the rise in alcohol consumption in the UK during the past three decades. The new epidemic of obesity is equally preventable. Of the 25% of the population now categorised as obese, most will have non-alcoholic fatty liver disease many (up to 1 in 20 of the UK population) will have ongoing infl ammation and scarring that fi nally leads to cirrhosis. Of those patients with cirrhosis, 5-10% will get liver cancer. This increasing burden of liver disease is added to by chronic viral hepatitis; annual deaths from hepatitis C have almost quadrupled since 1996 and about 75% of people infected are estimated to be still unrecognised. The same applies to chronic hepatitis B infection, in which progression to cirrhosis and liver cancer also happens. The number of silently infected individuals in the UK is increasing every year as a result of immigration from countries with a high prevalence of hepatitis B and hepatitis C infections. Costs to the UK's National Health Service are equally staggering, with estimates of £3.5 billion per year for alcohol-related health problems and £5.5 billion per year for the consequences of obesity. Obesity costs are almost certainly an underestimate now that the disorder is recognised as an important factor in several common cancers, including breast cancer and colon cancer.1 Obesity is a factor in metabolic disorders-the basis of diabetes, hypertension, cardiac diseases, and strokes. Furthermore, the poorest and most susceptible in society have the highest incidence of liver disorders, making liver disease a major issue for health inequalities. Of particular concern is the 2013 National Confi dential Enquiry into Patient Outcome and Death (NCEPOD) report,2 which showed that the care of patients acutely sick with liver disease dying in hospital was judged to be good in less than half of patients; other unacceptable fi ndings were the inadequate facilities and lack of expertise of those caring for patients. Also, it is increasingly evident that defi ciencies exist in primary care, which has crucial opportunities for early diagnosis and prevention of progressive disease. The aim of this Commission is to provide the strongest evidence base through involvement of experts from a wide cross-section of disciplines, making fi rm recommendations to reduce the unacceptable premature mortality and dsease burden from avoidable causes and to improve the standard of care for patients with liver disease in hospital. From the substantial number of recommendations given in our Commission, we selected those that will have the greatest eff ect and that need urgent implementation. Although the recommendations are based mostly on data from England, they have wider application to the UK as a whole, and are in accord with the present strategy for health-care policy by the Scottish Health Boards, the Health Department of Wales, and the Department of Health and Social Services in Northern Ireland. Our ten key recommendations are based on the strong evidence base and are in line with reports in 2014 of several other enquiries, including from the 2014 All Party Parliamentary Group on Hepatology3 and the All Party Parliamentary Group on alochol misuse. Results showing the value of a minimum unit price policy in targeting heavy drinkers were published in The Lancet in May, 2014, and the European Observatory on Health Polcy, together with the Department of Health and NHS England, has drawn attention to four areas of premature mortality, including liver disease, in which the UK lags behind other European countries. Such stark contrasts with our European neighbours are unacceptable and in this Commission we give clear, evidence-based policy proposals for the UK Government to use in closing the gap in liver disease

    Health-status outcomes with invasive or conservative care in coronary disease

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    BACKGROUND In the ISCHEMIA trial, an invasive strategy with angiographic assessment and revascularization did not reduce clinical events among patients with stable ischemic heart disease and moderate or severe ischemia. A secondary objective of the trial was to assess angina-related health status among these patients. METHODS We assessed angina-related symptoms, function, and quality of life with the Seattle Angina Questionnaire (SAQ) at randomization, at months 1.5, 3, and 6, and every 6 months thereafter in participants who had been randomly assigned to an invasive treatment strategy (2295 participants) or a conservative strategy (2322). Mixed-effects cumulative probability models within a Bayesian framework were used to estimate differences between the treatment groups. The primary outcome of this health-status analysis was the SAQ summary score (scores range from 0 to 100, with higher scores indicating better health status). All analyses were performed in the overall population and according to baseline angina frequency. RESULTS At baseline, 35% of patients reported having no angina in the previous month. SAQ summary scores increased in both treatment groups, with increases at 3, 12, and 36 months that were 4.1 points (95% credible interval, 3.2 to 5.0), 4.2 points (95% credible interval, 3.3 to 5.1), and 2.9 points (95% credible interval, 2.2 to 3.7) higher with the invasive strategy than with the conservative strategy. Differences were larger among participants who had more frequent angina at baseline (8.5 vs. 0.1 points at 3 months and 5.3 vs. 1.2 points at 36 months among participants with daily or weekly angina as compared with no angina). CONCLUSIONS In the overall trial population with moderate or severe ischemia, which included 35% of participants without angina at baseline, patients randomly assigned to the invasive strategy had greater improvement in angina-related health status than those assigned to the conservative strategy. The modest mean differences favoring the invasive strategy in the overall group reflected minimal differences among asymptomatic patients and larger differences among patients who had had angina at baseline
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