In vitro functional characterisation of IGF-I : VN-induced breast cancer progression

Members of the insulin-like growth factor (IGF) family have been shown to play critical roles in normal growth and development, as well as in tumour biology. The IGF system is complex and the biological effects of the IGFs are determined by their diverse interactions between many molecules, including their interactions with extracellular matrix (ECM) proteins. Recent studies have demonstrated that IGFs associate with the ECM protein vitronectin (VN) through IGF-binding proteins (IGFBP) and that this interaction modulates IGF-stimulated biological functions, namely cell migration and cell survival through the cooperative involvement of the type-I IGF receptor (IGF-1R) and VN-binding integrins. Since IGFs play important roles in the transformation and progression of breast cancer and VN has been found to be over-expressed at the leading edge of breast tumours, this project aimed to describe the effects of IGF-I:VN interactions on breast cell function. This was undertaken to dissect the molecular mechanisms underlying IGF-I:VN-induced responses and to design inhibitors to block the effects of such interactions. The studies described herein demonstrate that the increase in migration of MCF-7 breast cancer cells in response to the IGF-I:IGFBP-5:VN complex is accompanied by differential expression of genes known to be involved in migration, invasion and/or survival, including Tissue-factor (TF), Stratifin (SFN), Ephrin-B2, Sharp-2 and PAI-1. This „migration gene signature‟ was confirmed using real-time PCR analysis. Substitution of the native IGF-I within the IGF-I:IGFBP:VN complex with the IGF-I analogue, \[L24]\[A31]-IGF-I, which has a reduced affinity for the IGF-1R, failed to stimulate cell migration and interestingly, also failed to induce the differential gene expression. This supports the involvement of the IGF-1R in mediating these changes in gene expression. Furthermore, lentiviral shRNA-mediated stable knockdown of TF and SFN completely abrogated the increased cell migration induced by IGF-I:IGFBP:VN complexes in MCF-7 cells. Indeed, when these cells were grown in 3D Matrigel™ cultures a decrease in the overall size of the 3D spheroids in response to the IGF-I:IGFBP:VN complexes was observed compared to the parental MCF-7 cells. This suggests that TF and SFN have a role in complex-stimulated cell survival. Moreover, signalling studies performed on cells with the reduced expression of either TF or SFN had a decreased IGF-1R activation, suggesting the involvement of signalling pathways downstream of IGF-1R in TF- and/or SFN-mediated cell migration and cell survival. Taken together, these studies provide evidence for a common mechanism activated downstream of the IGF-1R that induces the expression of the „migration gene signature‟ in response to the IGF-I:IGFBP:VN complex that confers breast cancer cells the propensity to migrate and survive. Given the functional significance of the interdependence of ECM and growth factor (GF) interactions in stimulating processes key to breast cancer progression, this project aimed at developing strategies to prevent such growth factor:ECM interactions in an effort to inhibit the downstream functional effects. This may result in the reduction in the levels of ECM-bound IGF-I present in close proximity to the cells, thereby leading to a reduction in the stimulation of IGF-1R present on the cell surface. Indeed, the inhibition of IGF-I-mediated effects through the disruption of its association with ECM would not alter the physiological levels of IGF-I and potentially only exert effects in situations where abnormal over expression of ECM proteins are found; namely carcinomas and hyperproliferative diseases. In summary, this PhD project has identified novel, innovative and realistic strategies that can be used in vitro to inhibit the functions exerted by the IGF-I:IGFBP:VN multiprotein complexes critical for cancer progression, with a potential to be translated into in vivo investigations. Furthermore, TF and SFN were found to mediate IGF-I:IGFBP:VN-induced effects, thereby revealing their potential to be used as therapeutic targets or as predictive biomarkers for the efficacy of IGF-1R targeting therapies in breast cancer patients. In addition to its therapeutic and clinical scope, this PhD project has significantly contributed to the understanding of the role of the IGF system in breast tumour biology by providing valuable new information on the mechanistic events underpinning IGF-I:VN-mediated effects on breast cell functions. Furthermore, this is the first instance where favourable binding sites for IGF-II, IGFBP-3 and IGFBP-5 on VN have been identified. Taken together, this study has functionally characterised the interactions between IGF-I and VN and through innovative strategies has provided a platform for the development of novel therapies targeting these interactions and their downstream effects.

Cardiomyopathy classification : ongoing debate in the genomics era

Cardiomyopathies represent a group of diseases of the myocardium of the heart and include diseases both primarily of the cardiac muscle and systemic diseases leading to adverse effects on the heart muscle size, shape, and function. Traditionally cardiomyopathies were defined according to phenotypical appearance. Now, as our understanding of the pathophysiology of the different entities classified under each of the different phenotypes improves and our knowledge of the molecular and genetic basis for these entities progresses, the traditional classifications seem oversimplistic and do not reflect current understanding of this myriad of diseases and disease processes. Although our knowledge of the exact basis of many of the disease processes of cardiomyopathies is still in its infancy, it is important to have a classification system that has the ability to incorporate the coming tide of molecular and genetic information. This paper discusses how the traditional classification of cardiomyopathies based on morphology has evolved due to rapid advances in our understanding of the genetic and molecular basis for many of these clinical entities.

Improved ultra-performance liquid chromatography with electrospray ionization quadrupole-time-of-flight high-definition mass spectrometry method for the rapid analysis of the chemical constituents of a typical medical formula: Liuwei Dihuang Wan

Liuwei Dihuang Wan (LWD), a classic Chinese medicinal formulae, has been used to improve or restore declined functions related to aging and geriatric diseases, such as impaired mobility, vision, hearing, cognition and memory. It has attracted increasingly much attention as one of the most popular and valuable herbal medicines. However, the systematic analysis of the chemical constituents of LDW is difficult and thus has not been well established. In this paper, a rapid, sensitive and reliable ultra-performance liquid chromatography with electrospray ionization quadrupole time-of-flight high-definition mass spectrometry (UPLC-ESI-Q-TOF-MS) method with automated MetaboLynx analysis in positive and negative ion mode was established to characterize the chemical constituents of LDW. The analysis was performed on a Waters UPLCTM HSS T3 using a gradient elution system. MS/MS fragmentation behavior was proposed for aiding the structural identification of the components. Under the optimized conditions, a total of 50 peaks were tentatively characterized by comparing the retention time and MS data. It is concluded that a rapid and robust platform based on UPLC-ESI-Q-TOF-MS has been successfully developed for globally identifying multiple-constituents of traditional Chinese medicine prescriptions. This is the first report on systematic analysis of the chemical constituents of LDW. This article is protected by copyright. All rights reserved.

Association of a vitamin D receptor polymorphism with sporadic breast cancer development

Breast cancer is the leading cause of cancer death among Australian women and its incidence is annually increasing. Genetic factors are involved in the complex etiology of breast cancer. The seco-steroid hormone, 1.25 dihydroxy vitamin D3 can influence breast cancer cell growth in vitro. A number of studies have reported correlations between vitamin D receptor (VDR) gene polymorphisms and several diseases including prostate cancer and osteoporosis. In breast cancer, low vitamin D levels in serum are correlated with disease progression and bone metastases, a situation also noted in prostate cancer and suggesting the involvement of the VDR. In our study, 2 restriction fragment length polymorphisms (RFLP) in the 3' region (detected by Apa1 and Taq1) and an initiation codon variant in the 5' end of the VDR gene (detected by Fok1) were tested for association with breast cancer risk in 135 females with sporadic breast cancer and 110 cancer-free female controls. Allele frequencies of the 3' Apa1 polymorphism showed a significant association (p = 0.016; OR = 1.56, 95% CI = 1.09-2.24) while the Taq1 RFLP showed a similar trend (p = 0.053; OR = 1.45, 95% CI = 1.00-2.00). Allele frequencies of the Fok1 polymorphism were not significantly different (p = 0.97; OR = 0.99, 95% CI = 0.69-1.43) in the study population. Our results suggest that specific alleles of the VDR gene located near the 3' region may identify an increased risk for breast cancer and justify further investigation of the role of VDR in breast cancer.

TLR2, but Not TLR4, is required for effective host defence against Chlamydia respiratory tract infection in early life

Chlamydia pneumoniae commonly causes respiratory tract infections in children, and epidemiological investigations strongly link infection to the pathogenesis of asthma. The immune system in early life is immature and may not respond appropriately to pathogens. Toll-like receptor (TLR)2 and 4 are regarded as the primary pattern recognition receptors that sense bacteria, however their contribution to innate and adaptive immunity in early life remains poorly defined. We investigated the role of TLR2 and 4 in the induction of immune responses to Chlamydia muridarum respiratory infection, in neonatal wild-type (Wt) or TLR2-deficient (−/−), 4−/− or 2/4−/− BALB/c mice. Wt mice had moderate disease and infection. TLR2−/− mice had more severe disease and more intense and prolonged infection compared to other groups. TLR4−/− mice were asymptomatic. TLR2/4−/− mice had severe early disease and persistent infection, which resolved thereafter consistent with the absence of symptoms in TLR4−/− mice. Wt mice mounted robust innate and adaptive responses with an influx of natural killer (NK) cells, neutrophils, myeloid (mDCs) and plasmacytoid (pDCs) dendritic cells, and activated CD4+ and CD8+ T-cells into the lungs. Wt mice also had effective production of interferon (IFN)γ in the lymph nodes and lung, and proliferation of lymph node T-cells. TLR2−/− mice had more intense and persistent innate (particularly neutrophil) and adaptive cell responses and IL-17 expression in the lung, however IFNγ responses and T-cell proliferation were reduced. TLR2/4−/− mice had reduced innate and adaptive responses. Most importantly, neutrophil phagocytosis was impaired in the absence of TLR2. Thus, TLR2 expression, particularly on neutrophils, is required for effective control of Chlamydia respiratory infection in early life. Loss of control of infection leads to enhanced but ineffective TLR4-mediated inflammatory responses that prolong disease symptoms. This indicates that TLR2 agonists may be beneficial in the treatment of early life Chlamydia infections and associated diseases.

An exploratory study to evaluate whether medical nutrition therapy can improve dietary intake in hospital patients who eat poorly

Background and aims The Australasian Nutrition Care Day Survey (ANCDS) reported two-in-five patients consume ≤50% of the offered food in Australian and New Zealand hospitals. After controlling for confounders (nutritional status, age, disease type and severity), the ANCDS also established an independent association between poor food intake and increased in-hospital mortality. This study aimed to evaluate if medical nutrition therapy (MNT) could improve dietary intake in hospital patients eating poorly. Methods An exploratory pilot study was conducted in the respiratory, neurology and orthopaedic wards of an Australian hospital. At baseline, percentage food intake (0%, 25%, 50%, 75%, and 100%) was evaluated for each main meal and snack for a 24-hour period in patients hospitalised for ≥2 days and not under dietetic review. Patients consuming ≤50% of offered meals due to nutrition-impact symptoms were referred to ward dietitians for MNT. Food intake was re-evaluated on the seventh day following recruitment (post-MNT). Results 184 patients were observed over four weeks; 32 patients were referred for MNT. Although baseline and post-MNT data for 20 participants (68±17years, 65% females) indicated a significant increase in median energy and protein intake post-MNT (3600kJ/day, 40g/day) versus baseline (2250kJ/day, 25g/day) (p<0.05), the increased intake met only 50% of dietary requirements. Persistent nutrition impact symptoms affected intake. Conclusion In this pilot study whilst dietary intake improved, it remained inadequate to meet participants’ estimated requirements due to ongoing nutrition-impact symptoms. Appropriate medical management and early enteral feeding could be a possible solution for such patients.

Impact of ambient temperature on children's health : a systematic review

Children are vulnerable to temperature extremes. This paper aimed to review the literature regarding the relationship between ambient temperature and children’s health and to propose future research directions. A literature search was conducted in February 2012 using the databases including PubMed, ProQuest, ScienceDirect, Scopus and Web of Science. Empirical studies regarding the impact of ambient temperature on children’s mortality and morbidity were included. The existing literature indicates that very young children, especially children under one year of age, are particularly vulnerable to heat-related deaths. Hot and cold temperatures mainly affect cases of infectious diseases among children, including gastrointestinal diseases, malaria, hand, foot and mouse disease, and respiratory diseases. Paediatric allergic diseases, like eczema, are also sensitive to temperature extremes. During heat waves, the incidences of renal disease, fever and electrolyte imbalance among children increase significantly. Future research is needed to examine the balance between hot- and cold-temperature related mortality and morbidity among children; evaluate the impacts of cold spells on cause-specific mortality in children; identify the most sensitive temperature exposure and health outcomes to quantify the impact of temperature extremes on children; elucidate the possible modifiers of the temperature and children’s health relationship; and project children’s disease burden under different climate change scenarios.

A population-specific HTR2B stop codon predisposes to severe impulsivity

Impulsivity, describing action without foresight, is an important feature of several psychiatric diseases, suicidality and violent behaviour. The complex origins of impulsivity hinder identification of the genes influencing it and the diseases with which it is associated. Here we perform exon-focused sequencing of impulsive individuals in a founder population, targeting fourteen genes belonging to the serotonin and dopamine domain. A stop codon in HTR2B was identified that is common (minor allele frequency > 1%) but exclusive to Finnish people. Expression of the gene in the human brain was assessed, as well as the molecular functionality of the stop codon, which was associated with psychiatric diseases marked by impulsivity in both population and family-based analyses. Knockout of Htr2b increased impulsive behaviours in mice, indicative of predictive validity. Our study shows the potential for identifying and tracing effects of rare alleles in complex behavioural phenotypes using founder populations, and indicates a role for HTR2B in impulsivity.

Socio-demographic vulnerability to heatwave impacts in Brisbane, Australia : a time series analysis

Objective: Examining the association between socioeconomic disadvantage and heat-related emergency department (ED) visits during heatwave periods in Brisbane, 2000–2008. Methods: Data from 10 public EDs were analysed using a generalised additive model for disease categories, age groups and gender. Results: Cumulative relative risks (RR) for non-external causes other than cardiovascular and respiratory diseases were 1.11 and 1.05 in most and least disadvantaged areas, respectively. The pattern persisted on lags 0–2. Elevated risks were observed for all age groups above 15 years in all areas. However, with RRs of 1.19–1.28, the 65–74 years age group in more disadvantaged areas stood out, compared with RR=1.08 in less disadvantaged areas. This pattern was observed on lag 0 but did not persist. The RRs for male presentations were 1.10 and 1.04 in most and less disadvantaged areas; for females, RR was 1.04 in less disadvantaged areas. This pattern persisted across lags 0–2. Conclusions: Heat-related ED visits increased during heatwaves. However, due to overlapping confidence intervals, variations across socioeconomic areas should be interpreted cautiously. Implications: ED data may be utilised for monitoring heat-related health impacts, particularly on the first day of heatwaves, to facilitate prompt interventions and targeted resource allocation.

Can a text message a week improve breastfeeding?

Background Breastfeeding is recognised as the optimal method for feeding infants with health gains made by reducing infectious diseases in infancy; and chronic diseases, including obesity, in childhood, adolescence and adulthood. Despite this, exclusivity and duration in developed countries remains resistant to improvement. The objectives of this research were to test if an automated mobile phone text messaging intervention, delivering one text message a week, could increase “any” breastfeeding rates and improve breastfeeding self-efficacy and coping. Methods Women were eligible to participate if they were: over eighteen years; had an infant less than three months old; were currently breastfeeding; no diagnosed mental illness; and used a mobile phone . Women in the intervention group received MumBubConnect, a text messaging service with automated responses delivered once a week for 8 weeks. Women in the comparison group received their usual care and were sampled two years after the intervention group. Data collection included online surveys at two time points, week zero and week nine, to measure breastfeeding exclusivity and duration, coping, emotions, accountability and self-efficacy. A range of statistical analyses were used to test for differences between groups. Hierarchical regression was used to investigate change in breastfeeding outcome, between groups, adjusting for co-variates. Results The intervention group had 120 participants at commencement and 114 at completion, the comparison group had 114 participants at commencement and 86 at completion. MumBubConnect had a positive impact on the primary outcome of breastfeeding behaviors with women receiving the intervention more likely to continue exclusive breastfeeding; with a 6% decrease in exclusive breastfeeding in the intervention group, compared to a 14% decrease in the comparison group (p < 0.001). This remained significant after controlling for infant age, mother’s income, education and delivery type (p = 0.04). Women in the intervention group demonstrated active coping and were less likely to display emotions-focussed coping (p < .001). There was no discernible statistical effect on self-efficacy or accountability. Conclusions A fully automated text messaging services appears to improve exclusive breastfeeding duration. The service provides a well-accepted, personalised support service that empowers women to actively resolve breastfeeding issues. Trial registration Australian New Zealand Clinical Trials Registry: ACTRN12614001091695.

The impact of the environment on health in Mongolia : a systematic review

Mongolia has significant exposure to environmental risk factors because of poor environmental management and behaviors, and children are increasingly vulnerable to these threats. This study aimed to assess levels of exposure and summarize the evidence for associations between exposures to environmental risk factors and adverse health outcomes in Mongolia, with a particular focus on children. A systematic review was conducted using the PubMed, EMBASE, Web of Science, Global Health Library, CINAHL, CABI, Scopus, and mongolmed.mn electronic databases up to April 2014 . A total of 59 studies meeting the predetermined criteria were included. Results indicate that the Mongolian population has significant exposure to outdoor and indoor air pollution, metals, environmental tobacco smoke, and other chemical toxins, and these risk factors have been linked to respiratory and cardiovascular diseases among adults and respiratory diseases and neurodevelopmental disorders among children. Well-designed epidemiological investigations in vulnerable populations especially in pregnant women and children are recommended.

Indicator Bats Program: A System for the Global Acoustic Monitoring of Bats

Bats are an important component of mammalian biodiversity and fill such a wide array of ecological niches that they may offer an important multisensory bioindicator role in assessing ecosystem health. There is a need to monitor population trends of bats for their own sake because many populations face numerous environmental threats related to climate change, habitat loss, fragmentation, hunting, and emerging diseases. To be able to establish bat ultrasonic biodiversity trends as a reliable indicator, it is important to standardize monitoring protocols, data management, and analyses. This chapter discusses the main issues to be considered in developing a bat ultrasonic indicator. It focuses on the results from indicator bats program (iBats), a system for the global acoustic monitoring of bats, in Eastern Europe. Finally, the chapter reviews the strengths and weaknesses of the Program and considers the opportunities and threats that it may face in the future.

Five years of GWAS discovery

The past five years have seen many scientific and biological discoveries made through the experimental design of genome-wide association studies (GWASs). These studies were aimed at detecting variants at genomic loci that are associated with complex traits in the population and, in particular, at detecting associations between common single-nucleotide polymorphisms (SNPs) and common diseases such as heart disease, diabetes, auto-immune diseases, and psychiatric disorders. We start by giving a number of quotes from scientists and journalists about perceived problems with GWASs. We will then briefly give the history of GWASs and focus on the discoveries made through this experimental design, what those discoveries tell us and do not tell us about the genetics and biology of complex traits, and what immediate utility has come out of these studies. Rather than giving an exhaustive review of all reported findings for all diseases and other complex traits, we focus on the results for auto-immune diseases and metabolic diseases. We return to the perceived failure or disappointment about GWASs in the concluding section. © 2012 The American Society of Human Genetics.

The transcriptome of the bowhead whale Balaena mysticetus reveals adaptations of the longest‐lived mammal

Mammals vary dramatically in lifespan, by at least two-orders of magnitude, but the molecular basis for this difference remains largely unknown. The bowhead whale Balaena mysticetus is the longest-lived mammal known, with an estimated maximal lifespan in excess of two hundred years. It is also one of the two largest animals and the most cold-adapted baleen whale species. Here, we report the first genome-wide gene expression analyses of the bowhead whale, based on the de novo assembly of its transcriptome. Bowhead whale or cetacean-specific changes in gene expression were identified in the liver, kidney and heart, and complemented with analyses of positively selected genes. Changes associated with altered insulin signaling and other gene expression patterns could help explain the remarkable longevity of bowhead whales as well as their adaptation to a lipid-rich diet. The data also reveal parallels in candidate longevity adaptations of the bowhead whale, naked mole rat and Brandt's bat. The bowhead whale transcriptome is a valuable resource for the study of this remarkable animal, including the evolution of longevity and its important correlates such as resistance to cancer and other diseases.

Mortality reduction following the air pollution control measures during the 2010 Asian Games

Though increased particulate air pollution has been consistently associated with elevated mortality, evidence regarding whether diminished particulate air pollution would lead to mortality reduction is limited. Citywide air pollution mitigation program during the 2010 Asian Games in Guangzhou, China, provided such an opportunity. Daily mortality from non-accidental, cardiovascular and respiratory diseases was compared for 51 intervention days (November 1–December 21) in 2010 with the same calendar date of baseline years (2006–2009 and 2011). Relative risk (RR) and 95% confidence interval (95% CI) were estimated using a time series Poisson model, adjusting for day of week, public holidays, daily mean temperature and relative humidity. Daily PM10 (particle with aerodynamic diameter less than 10 μm) decreased from 88.64 μg/m3 during the baseline period to 80.61 μg/m3 during the Asian Games period. Other measured air pollutants and weather variables did not differ substantially. Daily mortality from non-accidental, cardiovascular and respiratory diseases decreased from 32, 11 and 6 during the baseline period to 25, 8 and 5 during the Games period, the corresponding RR for the Games period compared with the baseline period was 0.79 (95% CI: 0.73–0.86), 0.77 (95% CI: 0.66–0.89) and 0.68 (95% CI: 0.57–0.80), respectively. No significant decreases were observed in other months of 2010 in Guangzhou and intervention period in two control cities. This finding supports the efforts to reduce air pollution and improve public health through transportation restriction and industrial emission control.