Gut bacteria promote proliferation in benign S/RG/C2 colorectal tumour cells, and promote proliferation, migration and invasion in malignant HCT116 cells.

Colorectal cancer (CRC) is a significant global health burden with a rising incidence worldwide. Distinct bacterial populations are associated with CRC development and progression, and it is thought that the relationship between CRC and associated gut bacteria changes during the progression from normal epithelium to benign adenoma and eventually malignant carcinoma and metastasis. This study compared the interaction of CRC-associated species Enterotoxigenic Bacteroides fragilis, Enterococcus faecalis and Fusobacterium nucleatum and one probiotic species, Escherichia coli Nissle 1917 with a colorectal adenoma (S/RG/C2) and a colorectal adenocarcinoma (HCT116) derived cell line. Gentamicin protection assays showed that all species displayed higher attachment to benign tumour monolayers when compared to malignant monolayers. However, invasion of 3/4 species was higher in the HCT116 cells than in the adenoma cells. All species were found to persist within tumour cell monolayers for a minimum of 48 h under standard aerobic cell culture conditions, with persistence significantly higher in HCT116 cells. Downstream assays were performed to analyse the behaviour of S/RG/C2 and HCT116 cells post-infection and revealed that all species increased the tumour cell yield of both cell lines. The migratory and invasive potential of HCT116 cells was increased after infection with F. nucleatum; however, no species significantly altered these characteristics in S/RG/C2 cells. These results add to the growing evidence for the involvement of microorganisms in CRC progression and suggest that these interactions may be dependent on tumour cell-specific characteristics.

Landscape characteristics influence ranging behavior of Asian elephants at the human-wildlands interface in Myanmar.

CONTEXT: Asian elephant numbers are declining across much of their range driven largely by serious threats from land use change resulting in habitat loss and fragmentation. Myanmar, holding critical range for the species, is undergoing major developments due to recent sociopolitical changes. To effectively manage and conserve the remaining populations of endangered elephants in the country, it is crucial to understand their ranging behavior. OBJECTIVES: Our objectives were to (1) estimate the sizes of dry, wet, and annual ranges of wild elephants in Myanmar; and quantify the relationship between dry season (the period when human-elephant interactions are the most likely to occur) range size and configurations of agriculture and natural vegetation within the range, and (2) evaluate how percentage of agriculture within dry core range (50% AKDE range) of elephants relates to their daily distance traveled. METHODS: We used autocorrelated kernel density estimator (AKDE) based on a continuous-time movement modeling (ctmm) framework to estimate dry season (26 ranges from 22 different individuals), wet season (12 ranges from 10 different individuals), and annual range sizes (8 individuals), and reported the 95%, 50% AKDE, and 95% Minimum Convex Polygon (MCP) range sizes. We assessed how landscape characteristics influenced range size based on a broad array of 48 landscape metrics characterizing aspects of vegetation, water, and human features and their juxtaposition in the study areas. To identify the most relevant landscape metrics and simplify our candidate set of informative metrics, we relied on exploratory factor analysis and Spearman's rank correlation coefficient. Based on this analysis we adopted a final set of metrics into our regression analysis. In a multiple regression framework, we developed candidate models to explain the variation in AKDE dry season range sizes based on the previously identified, salient metrics of landscape composition. RESULTS: Elephant dry season ranges were highly variable averaging 792.0 km2 and 184.2 km2 for the 95% and 50% AKDE home ranges, respectively. We found both the shape and spatial configuration of agriculture and natural vegetation patches within an individual elephant's range play a significant role in determining the size of its range. We also found that elephants are moving more (larger energy expenditure) in ranges with higher percentages of agricultural area. CONCLUSION: Our results provide baseline information on elephant spatial requirements and the factors affecting them in Myanmar. This information is important for advancing future land use planning that takes into account space-use requirements for elephants. Failing to do so may further endanger already declining elephant populations in Myanmar and across the species' range.

Factors associated with advanced colorectal cancer differ between young and older adults in England: a population-based cohort study.

AIM: Advanced stage presentation of colorectal cancer is associated with poorer survival outcomes, particularly among young adults. This study aimed to determine whether demographic risk factors for advanced stage presentation differed between young and older adults. METHOD: Individual-level data on all incident colorectal cancers in people aged 20 years and above were extracted from the National Cancer Registration and Analysis Service database for the years 2012 to 2015. Patients were divided into two cohorts: young-onset colorectal cancer (YOCC) if aged 20-49 years and older-onset colorectal cancer (OOCC) if aged 50 years and above. Logistic regression was used to identify risk factors for advanced stage presentation, defined as TNM Stage III or IV, in each cohort. RESULTS: There were 7075 (5.2%) patients in the YOCC cohort and 128 345 (94.8%) patients in the OOCC cohort. Tumours in the YOCC cohort were more likely to be at an advanced stage (67.2% vs 55.3%, P < 0.001) and located distally (63.7% vs 55.4%, P < 0.001). No demographic factor was consistently associated with advanced stage presentation in the YOCC cohort. Among the OOCC cohort, increased social deprivation [OR (Index of Multiple Deprivation quintile 5 vs 1) = 1.11 (95% CI 1.07-1.16), P < 0.001], Black/Black British ethnicity [OR (baseline White) = 1.25 (95% CI 1.11-1.40), P < 0.001] and residence in the East Midlands [OR (baseline London) = 1.11 (95% CI 1.04-1.17), P = 0.001] were associated with advanced stage presentation. CONCLUSION: Demographic factors associated with advanced disease were influenced by age. The effects of social deprivation and ethnicity were only observed in older adults and mirror trends in screening uptake. Targeted interventions for high-risk groups are warranted.

Demographic trends in the incidence of young-onset colorectal cancer: a population-based study.

BACKGROUND: Evidence is emerging that the incidence of colorectal cancer is increasing in young adults, but the descriptive epidemiology required to better understand these trends is currently lacking. METHODS: A population-based cohort study was carried out including all adults aged 20-49 years diagnosed with colorectal cancer in England between 1974 and 2015. Data were extracted from the National Cancer Registration and Analysis Service database using ICD-9/10 codes for colorectal cancer. Temporal trends in age-specific incidence rates according to sex, anatomical subsite, index of multiple deprivation quintile and geographical region were analysed using Joinpoint regression. RESULTS: A total of 56 134 new diagnoses of colorectal cancer were analysed. The most sustained increase in incidence rate was in the group aged 20-29 years, which was mainly driven by a rise in distal tumours. The magnitude of incident rate increases was similar in both sexes and across Index of Multiple Deprivation quintiles, although the most pronounced increases in incidence occurred in the southern regions of England. CONCLUSION: Colorectal cancer should no longer be considered a disease of older people. Changes in incidence rates should be used to inform future screening policy, preventative strategies and research agendas, as well as increasing public understanding that younger people need to be aware of the symptoms of colorectal cancer.

ANTECEDENTES: Están apareciendo evidencias de que la incidencia del cáncer colorrectal (colorectal cancer, CRC) está aumentando en adultos jóvenes, pero se carece de la epidemiología descriptiva necesaria para comprender mejor estas tendencias. MÉTODOS: Se realizó un estudio de cohortes de base poblacional de todos los adultos de 20 a 49 años diagnosticados de CRC en Inglaterra entre 1974 y 2015. Los datos se extrajeron de la base de datos NCRAS utilizando los códigos ICD9/10 para el CRC. Las tendencias temporales en las tasas de incidencia específicas por edad (incidence rates, IR) según el sexo, la localización anatómica, el quintil del índice de privación múltiple (index of multiple deprivation, IMD) y la región geográfica se analizaron mediante un modelo de regresión joinpoint. RESULTADOS: Se analizaron un total de 56.134 nuevos diagnósticos de CRC. El aumento más sostenido en la IR se produjo en el grupo de edad de 20 a 29 años, principalmente a expensas de un incremento de los tumores distales. La magnitud de los aumentos de IR fue similar en ambos sexos y en los quintiles del IMD, aunque los aumentos más pronunciados en la incidencia se registraron en las regiones del sur de Inglaterra. CONCLUSIÓN: El CRC ya no debe ser considerado una enfermedad de las personas mayores: los cambios en las tasas de incidencia deberán tenerse en cuenta en las futuras políticas de cribado, en las estrategias preventivas y en los proyectos de investigación, así como para aumentar la toma de conciencia de la población de que las personas más jóvenes deben estar al corriente de los síntomas del CRC.

Correction: Brain structure in pediatric Tourette syndrome.

In this published article, members of 'The Tourette Association of America Neuroimaging Consortium' were not cited in PubMed. These consortium members are listed in the associated correction.

Targeting LGR5 in Colorectal Cancer: therapeutic gold or too plastic?

Leucine-rich repeat-containing G-protein coupled receptor (LGR5 or GPR49) potentiates canonical Wnt/ß-catenin signalling and is a marker of normal stem cells in several tissues, including the intestine. Consistent with stem cell potential, single isolated LGR5+ cells from the gut generate self-organising crypt/villus structures in vitro termed organoids or 'mini-guts', which accurately model the parent tissue. The well characterised deregulation of Wnt/ß-catenin signalling that occurs during the adenoma-carcinoma sequence in colorectal cancer (CRC) renders LGR5 an interesting therapeutic target. Furthermore, recent studies demonstrating that CRC tumours contain LGR5+ subsets and retain a degree of normal tissue architecture has heightened translational interest. Such reports fuel hope that specific subpopulations or molecules within a tumour may be therapeutically targeted to prevent relapse and induce long-term remissions. Despite these observations, many studies within this field have produced conflicting and confusing results with no clear consensus on the therapeutic value of LGR5. This review will recap the various oncogenic and tumour suppressive roles that have been described for the LGR5 molecule in CRC. It will further highlight recent studies indicating the plasticity or redundancy of LGR5+ cells in intestinal cancer progression and assess the overall merit of therapeutically targeting LGR5 in CRC.

Optimized delivery of siRNA into 3D tumor spheroid cultures in situ.

3D tissue culture provides a physiologically relevant and genetically tractable system for studying normal and malignant human tissues. Despite this, gene-silencing studies using siRNA has proved difficult. In this study, we have identified a cause for why traditional siRNA transfection techniques are ineffective in eliciting gene silencing in situ within 3D cultures and proposed a simple method for significantly enhancing siRNA entry into spheroids/organoids. In 2D cell culture, the efficiency of gene silencing is significantly reduced when siRNA complexes are prepared in the presence of serum. Surprisingly, in both 3D tumour spheroids and primary murine organoids, the presence of serum during siRNA preparation rapidly promotes entry and internalization of Cy3-labelled siRNA in under 2 hours. Conversely, siRNA prepared in traditional low-serum transfection media fails to gain matrigel or spheroid/organoid entry. Direct measurement of CTNNB1 mRNA (encoding ß-catenin) from transfected tumour spheroids confirmed a transient but significant knockdown of ß-catenin when siRNA:liposome complexes were formed with serum, but not when prepared in the presence of reduced-serum media (Opti-MEM). Our studies suggest a simple modification to standard lipid-based transfection protocols facilitates rapid siRNA entry and transient gene repression, providing a platform for researchers to improve siRNA efficiency in established 3D cultures.

LGR5 expression is regulated by EGF in early colorectal adenomas and governs EGFR inhibitor sensitivity.

BACKGROUND: LGR5 serves as a co-receptor for Wnt/ß-catenin signalling and marks normal intestinal stem cells; however, its role in colorectal cancer (CRC) remains controversial. LGR5+ cells are known to exist outside the stem cell niche during CRC progression, and the requirement for epidermal growth factor (EGF) signalling within early adenomas remains to be fully elucidated. METHODS: Epidermal growth factor and gefitinib treatments were performed in EGF-responsive LGR5+ early adenoma RG/C2 cells. 2D growth assays were measured using an IncuCyte. LGR5 or MEK1/2 silencing studies were executed using siRNA and LGR5 expression was assessed by qRT-PCR and immunoblotting. Ki67 level and cell cycle status were analysed by flow cytometry. RESULTS: Epidermal growth factor suppresses expression of LGR5 at both the transcript and protein level in colorectal adenoma and carcinoma cells. Suppression of LGR5 reduces the survival of EGF-treated adenoma cells by increasing detached cell yield but also inducing a proliferative state, as evidenced by elevated Ki67 level and enhanced cell cycle progression. Repression of LGR5 further increases the sensitivity of adenoma cells to EGFR inhibition. CONCLUSIONS: LGR5 has an important role in the EGF-mediated survival and proliferation of early adenoma cells and could have clinical utility in predicting response of CRC patients to EGFR therapy.

Potentiating the effects of radiotherapy in rectal cancer: the role of aspirin, statins and metformin as adjuncts to therapy.

BACKGROUND: Complete tumour response (pCR) to neo-adjuvant chemo-radiotherapy for rectal cancer is associated with a reduction in local recurrence and improved disease-free and overall survival, but is achieved in only 20-30% of patients. Drug repurposing for anti-cancer treatments is gaining momentum, but the potential of such drugs as adjuncts, to increase tumour response to chemo-radiotherapy in rectal cancer, is only just beginning to be recognised. METHODS: A systematic literature search was conducted and all studies investigating the use of drugs to enhance response to neo-adjuvant radiation in rectal cancer were included. 2137 studies were identified and following review 12 studies were extracted for full text review, 9 studies were included in the final analysis. RESULTS: The use of statins or aspirin during neo-adjuvant therapy was associated with a significantly higher rate of tumour downstaging. Statins were identified as a significant predictor of pCR and aspirin users had a greater 5-year progression-free survival and overall survival. Metformin use was associated with a significantly higher overall and disease-free survival, in a subset of diabetic patients. CONCLUSIONS: Aspirin, metformin and statins are associated with increased downstaging of rectal tumours and thus may have a role as adjuncts to neoadjuvant treatment, highlighting a clear need for prospective randomised controlled trials to determine their true impact on tumour response and overall survival.

Design, synthesis and characterization of linear unnatural amino acids for skin moisturization.

OBJECTIVES: This work aimed to design, synthesize and characterize replacement natural moisturizing factor (NMF) composed of modified hygroscopic linear amino acids to pre-empt or repair skin barrier dysfunction. METHODS: Following synthesis and characterization, thermo-gravimetric analysis and quantum mechanics molecular modelling quantified and depicted water binding to the new compounds. Deliquescence relative humidity demonstrated the water-scavenging ability of the compounds, whereas snake skin moisturizing studies showed they increased water uptake into snake skin. RESULTS: From thermal analysis, N-hydroxyglycine showed greatest water-holding capacity followed by N-hydroxyserine, l-homoserine and α-hydroxyglycine; coupled with quantum mechanics molecular modelling, between 8 and 12 molecules of water could associate with each molecule of either N-hydroxyglycine, N-hydroxyserine or l-homoserine. All of our modified amino acids were efficacious and induced similar or greater water uptake compared with the established moisturizing compounds hyaluronic acid, glycerine and urea in snake skin. Incorporated at 10% in Oilatum, N-hydroxyserine induced >200% greater moisture uptake into dry snake skin compared to treatment with water alone, with efficacy related to the molecule structure and ability to bind to 12 water molecules. Oilatum cream spiked with all our unnatural amino acid hydrotropes increased water uptake into snake skin compared with Oilatum alone. The compound series was designed to elucidate some structure - efficacy relationships. Amino acid chirality did not affect the water-holding capacity but did affect uptake into skin. Compounds with high melting points and bond energies tended to decrease water-holding capacity. With isosteric replacement, the more electronegative atoms gave greater water-holding capacities. CONCLUSIONS: This work demonstrates the potential of unnatural amino acid hydrotropes as skin moisturizers and has developed some predictive 'rules' for further design and refinement of chemical structures.

Nutrient stress alters the glycosylation status of LGR5 resulting in reduced protein stability and membrane localisation in colorectal tumour cells: implications for targeting cancer stem cells.

BACKGROUND: LGR5 is an important marker of intestinal stem cells and performs its vital functions at the cell membrane. Despite the importance of LGR5 to both normal and cancer stem cell biology, it is not known how microenvironmental stress affects the expression and subcellular distribution of the protein. METHODS: Nutrient stress was induced through glucose starvation. Glycosylation status was assessed using endoglycosidase or tunicamycin treatment. Flow cytometry and confocal microscopy were used to assess subcellular distribution of LGR5. RESULTS: Glucose deprivation altered the glycosylation status of LGR5 resulting in reduced protein stability and cell surface expression. Furthermore, inhibiting LGR5 glycosylation resulted in depleted surface expression and reduced localisation in the cis-Golgi network. CONCLUSIONS: Nutrient stress within a tumour microenvironment has the capacity to alter LGR5 protein stability and membrane localisation through modulation of LGR5 glycosylation status. As LGR5 surface localisation is required for enhanced Wnt signalling, this is the first report to show a mechanism by which the microenvironment could affect LGR5 function.

GABA-mediated changes in inter-hemispheric beta frequency activity in early-stage Parkinson's disease.

In Parkinson's disease (PD), elevated beta (15-35Hz) power in subcortical motor networks is widely believed to promote aspects of PD symptomatology, moreover, a reduction in beta power and coherence accompanies symptomatic improvement following effective treatment with l-DOPA. Previous studies have reported symptomatic improvements that correlate with changes in cortical network activity following GABAA receptor modulation. In this study we have used whole-head magnetoencephalography to characterize neuronal network activity, at rest and during visually cued finger abductions, in unilaterally symptomatic PD and age-matched control participants. Recordings were then repeated following administration of sub-sedative doses of the hypnotic drug zolpidem (0.05mg/kg), which binds to the benzodiazepine site of the GABAA receptor. A beamforming based 'virtual electrode' approach was used to reconstruct oscillatory power in the primary motor cortex (M1), contralateral and ipsilateral to symptom presentation in PD patients or dominant hand in control participants. In PD patients, contralateral M1 showed significantly greater beta power than ipsilateral M1. Following zolpidem administration contralateral beta power was significantly reduced while ipsilateral beta power was significantly increased resulting in a hemispheric power ratio that approached parity. Furthermore, there was highly significant correlation between hemispheric beta power ratio and Unified Parkinson's Disease Rating Scale (UPDRS). The changes in contralateral and ipsilateral beta power were reflected in pre-movement beta desynchronization and the late post-movement beta rebound. However, the absolute level of movement-related beta desynchronization was not altered. These results show that low-dose zolpidem not only reduces contralateral beta but also increases ipsilateral beta, while rebalancing the dynamic range of M1 network oscillations between the two hemispheres. These changes appear to underlie the symptomatic improvements afforded by low-dose zolpidem.

Exploring experiences and understandings of pain in adults with intellectual disabilities.

BACKGROUND: People with intellectual disabilities (ID) are at risk that their health problems, many of which cause pain, go unrecognised and untreated. Their understanding and personal experiences of pain have received little research attention. METHOD: Information was collected from 15 adults with ID using semi-structured interviews about their experiences and understanding of pain. Transcripts were analysed using content analysis. RESULTS: Participants described pain using negative meanings and strong imagery, with various causes of pain suggested, but said little about how they coped with pain. Participants varied in whether they reported pains to carers, some choosing to hide the experience. There seemed a general belief that others can tell when someone is in pain. CONCLUSIONS: Conversations regarding pain with adults with ID are a real challenge; health-care staff need to think carefully about the questions they ask. Possessing verbal skills cannot be taken as an indication that pain will be communicated.

Brian Barry: innovative contributions to transdermal and topical drug delivery.

Brian Barry published over 300 research articles across topics ranging from colloid science, vasoconstriction and the importance of thermodynamics in dermal drug delivery to exploring the structure and organisation of the stratum corneum barrier lipids and numerous strategies for improving topical and transdermal drug delivery, including penetration enhancers, supersaturation, coacervation, eutectic formation and the use of varied liposomes. As research in the area blossomed in the early 1980s, Brian wrote the book that became essential reading for both new and established dermal delivery scientists, explaining the background mathematics and principles through to formulation design. Brian also worked with numerous scientists, as collaborators and students, who have themselves taken his rigorous approach to scientific investigation into their own research groups. This paper can only describe a small fraction of the many significant contributions that Brian made to the field during his 40-year academic career.