Modulation of TRAIL resistance in colon carcinoma cells: Different contributions of DR4 and DR5

<p>Abstract</p> <p>Background</p> <p>rhTRAIL is a therapeutic agent, derived from the TRAIL cytokine, which induces apoptosis in cancer cells by activating the membrane death receptors 4 and 5 (DR4 and DR5). Here, we investigated each receptor's contribution to rhTRAIL sensitivity and rhTRAIL resistance. We assessed whether agonistic DR4 or DR5 antibodies could be used to circumvent rhTRAIL resistance, alone or in combination with various chemotherapies.</p> <p>Methods</p> <p>Our study was performed in an isogenic model comprised of the SW948 human colon carcinoma cell line and its rhTRAIL resistant sub-line SW948-TR. Effects of rhTRAIL and agonistic DR4/DR5 antibodies on cell viability were measured using MTT assays and identification of morphological changes characteristic of apoptosis, after acridine orange staining. Sensitivity to the different death receptor ligands was stimulated using pretreatment with the cytokine IFN-gamma and the proteasome inhibitor MG-132. To investigate the mechanisms underlying the changes in rhTRAIL sensitivity, alterations in expression levels of targets of interest were measured by Western blot analysis. Co-immunoprecipitation was used to determine the composition of the death-inducing signalling complex at the cell membrane.</p> <p>Results</p> <p>SW948 cells were sensitive to all three of the DR-targeting agents tested, although the agonistic DR5 antibody induced only weak caspase 8 cleavage and limited apoptosis. Surprisingly, agonistic DR4 and DR5 antibodies induced equivalent DISC formation and caspase 8 cleavage at the level of their individual receptors, suggesting impairment of further caspase 8 processing upon DR5 stimulation. SW948-TR cells were cross-resistant to all DR-targeting agents as a result of decreased caspase 8 expression levels. Caspase 8 protein expression was restored by MG-132 and IFN-gamma pretreatment, which also re-established sensitivity to rhTRAIL and agonistic DR4 antibody in SW948-TR. Surprisingly, MG-132 but not IFN-gamma could also increase DR5-mediated apoptosis in SW948-TR.</p> <p>Conclusions</p> <p>These results highlight a critical difference between DR4- and DR5-mediated apoptotic signaling modulation, with possible implications for future combinatorial regimens.</p

Developing a core outcome set for future infertility research: an international consensus development study

STUDY QUESTION Can a core outcome set to standardize outcome selection, collection and reporting across future infertility research be developed? SUMMARY ANSWER A minimum data set, known as a core outcome set, has been developed for randomized controlled trials (RCTs) and systematic reviews evaluating potential treatments for infertility. WHAT IS KNOWN ALREADY Complex issues, including a failure to consider the perspectives of people with fertility problems when selecting outcomes, variations in outcome definitions and the selective reporting of outcomes on the basis of statistical analysis, make the results of infertility research difficult to interpret. STUDY DESIGN, SIZE, DURATION A three-round Delphi survey (372 participants from 41 countries) and consensus development workshop (30 participants from 27 countries). PARTICIPANTS/MATERIALS, SETTING, METHODS Healthcare professionals, researchers and people with fertility problems were brought together in an open and transparent process using formal consensus science methods. MAIN RESULTS AND THE ROLE OF CHANCE The core outcome set consists of: viable intrauterine pregnancy confirmed by ultrasound (accounting for singleton, twin and higher multiple pregnancy); pregnancy loss (accounting for ectopic pregnancy, miscarriage, stillbirth and termination of pregnancy); live birth; gestational age at delivery; birthweight; neonatal mortality; and major congenital anomaly. Time to pregnancy leading to live birth should be reported when applicable. LIMITATIONS, REASONS FOR CAUTION We used consensus development methods which have inherent limitations, including the representativeness of the participant sample, Delphi survey attrition and an arbitrary consensus threshold. WIDER IMPLICATIONS OF THE FINDINGS Embedding the core outcome set within RCTs and systematic reviews should ensure the comprehensive selection, collection and reporting of core outcomes. Research funding bodies, the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) statement, and over 80 specialty journals, including the Cochrane Gynaecology and Fertility Group, Fertility and Sterility and Human Reproduction, have committed to implementing this core outcome set. STUDY FUNDING/COMPETING INTEREST(S) This research was funded by the Catalyst Fund, Royal Society of New Zealand, Auckland Medical Research Fund and Maurice and Phyllis Paykel Trust. The funder had no role in the design and conduct of the study, the collection, management, analysis or interpretation of data, or manuscript preparation. B.W.J.M. is supported by a National Health and Medical Research Council Practitioner Fellowship (GNT1082548). S.B. was supported by University of Auckland Foundation Seelye Travelling Fellowship. S.B. reports being the Editor-in-Chief of Human Reproduction Open and an editor of the Cochrane Gynaecology and Fertility group. J.L.H.E. reports being the Editor Emeritus of Human Reproduction. J.M.L.K. reports research sponsorship from Ferring and Theramex. R.S.L. reports consultancy fees from Abbvie, Bayer, Ferring, Fractyl, Insud Pharma and Kindex and research sponsorship from Guerbet and Hass Avocado Board. B.W.J.M. reports consultancy fees from Guerbet, iGenomix, Merck, Merck KGaA and ObsEva. C.N. reports being the Co Editor-in-Chief of Fertility and Sterility and Section Editor of the Journal of Urology, research sponsorship from Ferring, and retains a financial interest in NexHand. A.S. reports consultancy fees from Guerbet. E.H.Y.N. reports research sponsorship from Merck. N.L.V. reports consultancy and conference fees from Ferring, Merck and Merck Sharp and Dohme. The remaining authors declare no competing interests in relation to the work presented. All authors have completed the disclosure form

High prevalence of overweight among adolescents in Ho Chi Minh City, Vietnam

Background: Two previous surveys conducted in Ho Chi Minh City revealed an increasing prevalence of overweight and obese adolescents, from 5.9% in 2002 to 11.7% in 2004. From 2004 to 2010, the government set up and implemented health promotion programs to promote physical activity and good nutritional habits in order to prevent overweight and obesity in children and adolescents. Our study aimed to estimate the prevalence of overweight and obesity among adolescents in urban areas of Ho Chi Minh City in 2010. Methods. A representative sample of 1,989 students aged 11-14 years was selected using a multistage cluster sampling method. 23 schools were randomly selected from the full list of all public junior high schools. In each selected school, 2 classes were chosen at random and all students from the class were examined. Age- and sex-adjusted overweight and obesity were defined using International Obesity Taskforce cut-offs. Results: The prevalences of overweight and obesity were 17.8% and 3.2%, respectively. Prevalences of overweight and obesity were significantly higher in boys (22%, 5.4%) than in girls (13.3%, 1.3%, p&lt;0.001) and higher in children from districts with a high economic level (20.5%, 3.8%) than in those from districts with a low economic level (12.1%, 3.8%, p&lt;0.001). Additionally, children living in wealthier families were more overweight and obese than those living in less wealthy families. When using WHO cutoffs, the overall prevalences of overweight and obesity reached 19.6% and 7.9%, respectively. Conclusion: Our study's findings suggest that the prevalence of overweight and obesity among secondary school students remains high, especially among boys living in wealthier families. Public health programs should therefore be developed or improved in order to promote good eating habits and physical activity among youth in HCMC. © 2013 Ngoc Nguyen et al; licensee BioMed Central Ltd