24 research outputs found

    MicroRNA Controlled Adenovirus Mediates Anti-Cancer Efficacy without Affecting Endogenous MicroRNA Activity

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    MicroRNAs are small non-coding RNA molecules that regulate mRNA translation and stability by binding to complementary sequences usually within the 3′ un-translated region (UTR). We have previously shown that the hepatic toxicity caused by wild-type Adenovirus 5 (Ad5WT) in mice can be prevented by incorporating 4 binding sites for the liver-specific microRNA, mir122, into the 3′ UTR of E1A mRNA. This virus, termed Ad5mir122, is a promising virotherapy candidate and causes no obvious liver pathology. Herein we show that Ad5mir122 maintains wild-type lytic activity in cancer cells not expressing mir122 and assess any effects of possible mir122 depletion in host cells. Repeat administration of 2×1010 viral particles of Admir122 to HepG2 tumour bearing mice showed significant anti-cancer efficacy. RT-QPCR showed that E1A mRNA was down-regulated 29-fold in liver when compared to Ad5WT. Western blot for E1A confirmed that all protein variants were knocked down. RT-QPCR for mature mir122 in infected livers showed that quantity of mir122 remained unaffected. Genome wide mRNA microarray profiling of infected livers showed that although the transcript level of >3900 different mRNAs changed more than 2-fold following Ad5WT infection, less than 600 were changed by Ad5mir122. These were then filtered to select mRNAs that were only altered by Ad5mir122 and the remaining 21 mRNAs were compared to predicted mir122 targets. No mir122 target mRNAs were affected by Ad5 mir122. These results demonstrate that the exploitation of microRNA regulation to control virus replication does not necessarily affect the level of the microRNA or the endogenous mRNA targets

    How patient and community involvement in diabetes research influences health outcomes : a realist review

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    Background Patient and public involvement in diabetes research is an international requirement, but little is known about the relationship between the process of involvement and health outcomes. Objective This realist review identifies who benefits from different types of involvement across different contexts and circumstances. Search strategies Medline, CINAHL and EMBASE were searched to identify interventions using targeted, embedded or collaborative involvement to reduce risk and promote self‐management of diabetes. People at risk/with diabetes, providers and community organizations with an interest in addressing diabetes were included. There were no limitations on date, language or study type. Data extraction and synthesis Data were extracted from 29 projects using elements from involvement frameworks. A conceptual analysis of involvement types was used to complete the synthesis. Main results Projects used targeted (4), embedded (8) and collaborative (17) involvement. Productive interaction facilitated over a sufficient period of time enabled people to set priorities for research. Partnerships that committed to collaboration increased awareness of diabetes risk and mobilized people to co‐design and co‐deliver diabetes interventions. Cultural adaptation increased relevance and acceptance of the intervention because they trusted local delivery approaches. Local implementation produced high levels of recruitment and retention, which project teams associated with achieving diabetes health outcomes. Discussion and Conclusions Achieving understanding of community context, developing trusting relationships across sectors and developing productive partnerships were prerequisites for designing research that was feasible and locally relevant. The proportion of diabetes studies incorporating these elements is surprisingly low. Barriers to resourcing partnerships need to be systematically addressed

    In vivo imaging of pancreatic tumours and liver metastases using 7 Tesla MRI in a murine orthotopic pancreatic cancer model and a liver metastases model

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    <p>Abstract</p> <p>Background</p> <p>Pancreatic cancer is the fourth leading cause of tumour death in the western world. However, appropriate tumour models are scarce. Here we present a syngeneic murine pancreatic cancer model using 7 Tesla MRI and evaluate its clinical relevance and applicability.</p> <p>Methods</p> <p>6606PDA murine pancreatic cancer cells were orthotopically injected into the pancreatic head. Liver metastases were induced through splenic injection. Animals were analyzed by MRI three and five weeks following injection. Tumours were detected using T2-weighted high resolution sequences. Tumour volumes were determined by callipers and MRI. Liver metastases were analyzed using gadolinium-EOB-DTPA and T1-weighted 3D-Flash sequences. Tumour blood flow was measured using low molecular gadobutrol and high molecular gadolinium-DTPA.</p> <p>Results</p> <p>MRI handling and applicability was similar to human systems, resolution as low as 0.1 mm. After 5 weeks tumour volumes differed significantly (p < 0.01) when comparing calliper measurments (n = 5, mean 1065 mm<sup>3</sup>+/-243 mm<sup>3</sup>) with MRI (mean 918 mm<sup>3</sup>+/-193 mm<sup>3</sup>) with MRI being more precise. Histology (n = 5) confirmed MRI tumour measurements (mean size MRI 38.5 mm<sup>2</sup>+/-22.8 mm<sup>2 </sup>versus 32.6 mm<sup>2</sup>+/-22.6 mm<sup>2 </sup>(histology), p < 0,0004) with differences due to fixation and processing of specimens. After splenic injection all mice developed liver metastases with a mean of 8 metastases and a mean volume of 173.8 mm<sup>3</sup>+/-56.7 mm<sup>3 </sup>after 5 weeks. Lymphnodes were also easily identified. Tumour accumulation of gadobutrol was significantly (p < 0.05) higher than gadolinium-DTPA. All imaging experiments could be done repeatedly to comply with the 3R-principle thus reducing the number of experimental animals.</p> <p>Conclusions</p> <p>This model permits monitoring of tumour growth and metastasis formation in longitudinal non-invasive high-resolution MR studies including using contrast agents comparable to human pancreatic cancer. This multidisciplinary environment enables radiologists, surgeons and physicians to further improve translational research and therapies of pancreatic cancer.</p

    Functionally Distinct Subpopulations of CpG-Activated Memory B Cells

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    During the human B cell (Bc) recall response, rapid cell division results in multiple Bc subpopulations. The TLR-9 agonist CpG oligodeoxynucleotide, combined with cytokines, causes Bc activation and division in vitro and increased CD27 surface expression in a sub-population of Bc. We hypothesized that the proliferating CD27lo subpopulation, which has a lower frequency of antibody-secreting cells (ASC) than CD27hi plasmablasts, provides alternative functions such as cytokine secretion, costimulation, or antigen presentation. We performed genome-wide transcriptional analysis of CpG activated Bc sorted into undivided, proliferating CD27lo and proliferating CD27hi subpopulations. Our data supported an alternative hypothesis, that CD27lo cells are a transient pre-plasmablast population, expressing genes associated with Bc receptor editing. Undivided cells had an active transcriptional program of non-ASC B cell functions, including cytokine secretion and costimulation, suggesting a link between innate and adaptive Bc responses. Transcriptome analysis suggested a gene regulatory network for CD27lo and CD27hi Bc differentiation

    The role of epigenetics in renal ageing

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    An ability to separate natural ageing processes from processes specific to morbidities is required to understand the heterogeneity of age-related organ dysfunction. Mechanistic insight into how epigenetic factors regulate ageing throughout the life course, linked to a decline in renal function with ageing, is already proving to be of value in the analyses of clinical and epidemiological cohorts. Noncoding RNAs provide epigenetic regulatory circuits within the kidney, which reciprocally interact with DNA methylation processes, histone modification and chromatin. These interactions have been demonstrated to reflect the biological age and function of renal allografts. Epigenetic factors control gene expression and activity in response to environmental perturbations. They also have roles in highly conserved signalling pathways that modulate ageing, including the mTOR and insulin/insulin-like growth factor signalling pathways, and regulation of sirtuin activity. Nutrition, the gut microbiota, inflammation and environmental factors, including psychosocial and lifestyle stresses, provide potential mechanistic links between the epigenetic landscape of ageing and renal dysfunction. Approaches to modify the renal epigenome via nutritional intervention, targeting the methylome or targeting chromatin seem eminently feasible, although caution is merited owing to the potential for intergenerational and transgenerational effects
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