AICAR inhibits adipocyte differentiation in 3T3L1 and restores metabolic alterations in diet-induced obesity mice model

BACKGROUND: Obesity is one of the principal causative factors involved in the development of metabolic syndrome. AMP-activated protein kinase (AMPK) is an energy sensor that regulates cellular metabolism. The role of AMP-activated protein kinase in adipocyte differentiation is not completely understood, therefore, we examined the effect of 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside (AICAR), a pharmacological activator of AMP-activated protein kinase (AMPK) on adipocyte differentiation in 3T3L1 cells and in a mouse Diet induced obesity (DIO) model. METHODS: To examine the effect of AICAR on adipocyte differentiation in 3T3L1 cells and in a mouse Diet induced obesity (DIO) model, 3T3L1 cells were differentiatied in the presence or absence of different concentration of AICAR and neutral lipid content and expression of various adipocyte-specific transcription factors were examined. In vivo study, treated and untreated mice with AICAR (0.1–0.5 mg/g body weight) were fed high-fat diet (60% kcal% fat) to induce DIO and several parameters were studied. RESULTS: AICAR blocked adipogenic conversion in 3T3L1 cells along with significant decrease in the neutral lipid content by downregulating several adipocyte-specific transcription factors including peroxisome proliferators-activated receptor γ (PPARγ), C/EBPα and ADD1/SREBP1, which are critical for adipogenesis in vitro. Moreover, intraperitoneal administration of AICAR (0.5 mg g/body weight) to mice fed with high-fat diet (60% kcal% fat) to induce DIO, significantly blocked the body weight gain and total content of epididymal fat in these mice over a period of 6 weeks. AICAR treatment also restored normal adipokine levels and resulted in significant improvement in glucose tolerance and insulin sensitivity. The reduction in adipose tissue content in AICAR treated DIO mice was due to reduction in lipid accumulation in the pre-existing adipocytes. However, no change was observed in the expression of PPARγ, C/EBPα and ADD1/SREBP1 transcription factors in vivo though PGC1α expression was significantly induced. CONCLUSION: This study suggests that AICAR inhibits adipocyte differentiation via downregulation of expression of adipogenic factors in vitro and reduces adipose tissue content in DIO mice by activating expression of PGC1α without inhibiting adipocyte-specific transcription factors in DIO mice

Analysis of the potential of cancer cell lines to release tissue factor-containing microvesicles: correlation with tissue factor and PAR2 expression

BackgroundDespite the association of cancer-derived circulating tissue factor (TF)-containing microvesicles and hypercoagulable state, correlations with the incidence of thrombosis remain unclear.MethodsIn this study the upregulation of TF release upon activation of various cancer cell lines, and the correlation with TF and PAR2 expression and/or activity was examined. Microvesicle release was induced by PAR2 activation in seventeen cell lines and released microvesicle density, microvesicle-associated TF activity, and phoshpatidylserine-mediated activity were measured. The time-course for TF release was monitored over 90 min in each cell line. In addition, TF mRNA expression, cellular TF protein and cell-surface TF activities were quantified. Moreover, the relative expression of PAR2 mRNA and cellular protein were analysed. Any correlations between the above parameters were examined by determining the Pearson’s correlation coefficients.ResultsTF release as microvesicles peaked between 30–60 min post-activation in the majority of cell lines tested. The magnitude of the maximal TF release positively correlated with TF mRNA (c = 0.717; p

Validation of the Oxford WebQ online 24-hour dietary questionnaire using biomarkers

Oxford WebQ is an online dietary questionnaire covering 24 hours, appropriate for repeated administration in large-scale prospective studies including UK Biobank and the Million Women Study. We compared performance of the Oxford WebQ and a traditional interviewer-administered multi-pass 24-hour recall against biomarkers for protein, potassium and total sugar intake, and total energy expenditure estimated by accelerometry. 160 participants were recruited between 2014 and 2016 in London, UK, and measured at 3 non-consecutive time-points. The measurement error model simultaneously compared all 3 methods. Attenuation factors for protein, potassium, sugars and total energy intake estimated by the mean of 2 Oxford WebQs were 0.37, 0.42, 0.45, and 0.31 respectively, with performance improving incrementally for the mean of more measures. Correlation between the mean of 2 Oxford WebQs and estimated true intakes, reflecting attenuation when intake is categorised or ranked, was 0.47, 0.39, 0.40, and 0.38 respectively, also improving with repeated administration. These were similar to the more administratively burdensome interviewer-based recall. Using objective biomarkers as the standard, Oxford WebQ performs well across key nutrients in comparison with more administratively burdensome interviewer-based 24-hour recalls. Attenuation improves when the average is taken over repeated administration, reducing measurement error bias in assessment of diet-disease associations

Critical research gaps and translational priorities for the successful prevention and treatment of breast cancer

INTRODUCTION Breast cancer remains a significant scientific, clinical and societal challenge. This gap analysis has reviewed and critically assessed enduring issues and new challenges emerging from recent research, and proposes strategies for translating solutions into practice. METHODS More than 100 internationally recognised specialist breast cancer scientists, clinicians and healthcare professionals collaborated to address nine thematic areas: genetics, epigenetics and epidemiology; molecular pathology and cell biology; hormonal influences and endocrine therapy; imaging, detection and screening; current/novel therapies and biomarkers; drug resistance; metastasis, angiogenesis, circulating tumour cells, cancer 'stem' cells; risk and prevention; living with and managing breast cancer and its treatment. The groups developed summary papers through an iterative process which, following further appraisal from experts and patients, were melded into this summary account. RESULTS The 10 major gaps identified were: (1) understanding the functions and contextual interactions of genetic and epigenetic changes in normal breast development and during malignant transformation; (2) how to implement sustainable lifestyle changes (diet, exercise and weight) and chemopreventive strategies; (3) the need for tailored screening approaches including clinically actionable tests; (4) enhancing knowledge of molecular drivers behind breast cancer subtypes, progression and metastasis; (5) understanding the molecular mechanisms of tumour heterogeneity, dormancy, de novo or acquired resistance and how to target key nodes in these dynamic processes; (6) developing validated markers for chemosensitivity and radiosensitivity; (7) understanding the optimal duration, sequencing and rational combinations of treatment for improved personalised therapy; (8) validating multimodality imaging biomarkers for minimally invasive diagnosis and monitoring of responses in primary and metastatic disease; (9) developing interventions and support to improve the survivorship experience; (10) a continuing need for clinical material for translational research derived from normal breast, blood, primary, relapsed, metastatic and drug-resistant cancers with expert bioinformatics support to maximise its utility. The proposed infrastructural enablers include enhanced resources to support clinically relevant in vitro and in vivo tumour models; improved access to appropriate, fully annotated clinical samples; extended biomarker discovery, validation and standardisation; and facilitated cross-discipline working. CONCLUSIONS With resources to conduct further high-quality targeted research focusing on the gaps identified, increased knowledge translating into improved clinical care should be achievable within five years

Estrogen receptor-α polymorphism in a Taiwanese clinical breast cancer population: a case–control study

INTRODUCTION: Receptor-mediated estrogen activation participates in the development and progression of breast cancer. Estrogen receptor (ER)-α polymorphism has been found to be associated with breast cancer and clinical features of the disease in Caucasians. Epidemiologic studies have revealed that age–incidence patterns of breast cancer in Asians differ from those in Caucasians. Genomic data for ER-α in either population is therefore of value in the clinical setting for that ethnic group. METHODS: A case–control study was conducted to establish a database of ER-α polymorphisms in a Taiwanese population in order to compare Western and Taiwanese (Asian) distributions and to evaluate ER-α polymorphism as an indicator of clinical outcome. The ER-α gene was scanned in a Taiwanese clinical breast cancer group (189 patients) and in healthy individuals (177 healthy control individuals). PCR single-strand conformation polymorphism technology was employed and real-time PCR melting curve analysis was performed. RESULTS: Three sites of silent single nucleotide polymorphism (SNPs) were found, as reported previously in Western studies, but at significantly different frequencies. Among the three SNPs, the frequency of allele 1 (TCT → TCC) in codon 10 was significantly lower in breast cancer patients (32.0%) than in control individuals (40.4%; P = 0.018). We found that allele 1 (ACG → ACA) in codon 594 was less common in breast cancer patients with a family history of breast cancer (5.9%) than in those without such a history (19.6%; P = 0.049). Individually, both allele 1 in codon 325 (CCC → CCG) and allele 1 in codon 594 exhibited a reverse association with the occurrence of lymph node metastasis. Furthermore, incorporation of both SNP markers further increased predictive accuracy. CONCLUSIONS: Our data suggest that ER-α polymorphisms are correlated with various aspects of breast cancer in Taiwan. ER-α genotype, as determined during presurgical evaluation, might represent a surrogate marker for predicting breast cancer lymph node metastasis

Association of Coagulation Activation with Clinical Complications in Sickle Cell Disease

Background: The contribution of hypercoagulability to the pathophysiology of sickle cell disease (SCD) remains poorly defined. We sought to evaluate the association of markers of coagulation and platelet activation with specific clinical complications and laboratory variables in patients with SCD. Design and Methods: Plasma markers of coagulation activation (D-dimer and TAT), platelet activation (soluble CD40 ligand), microparticle-associated tissue factor (MPTF) procoagulant activity and other laboratory variables were obtained in a cohort of patients with SCD. Tricuspid regurgitant jet velocity was determined by Doppler echocardiography and the presence/history of clinical complications was ascertained at the time of evaluation, combined with a detailed review of the medical records. Results: No significant differences in the levels of D-dimer, TAT, soluble CD40 ligand, and MPTF procoagulant activity were observed between patients in the SS/SD/Sb 0 thalassemia and SC/Sb + thalassemia groups. Both TAT and D-dimer were significantly correlated with measures of hemolysis (lactate dehydrogenase, indirect bilirubin and hemoglobin) and soluble vascular cell adhesion molecule-1. In patients in the SS/SD/Sb 0 thalassemia group, D-dimer was associated with a history of stroke (p = 0.049), TAT was associated with a history of retinopathy (p = 0.0176), and CD40 ligand was associated with the frequency of pain episodes (p = 0.039). In multivariate analyses, D-dimer was associated with reticulocyte count, lactat

Endogenous sex hormones and prostate cancer: a quantitative review of prospective studies

This paper presents a quantitative review of the data from eight prospective epidemiological studies, comparing mean serum concentrations of sex hormones in men who subsequently developed prostate cancer with those in men who remained cancer free. The hormones reviewed have been postulated to be involved in the aetiology of prostate cancer: androgens and their metabolites testosterone (T), non-SHBG-bound testosterone (non-SHBG-bound T), di-hydrotestosterone (DHT), androstanediol glucuronide (A-diol-g), androstenedione (A-dione), dehydroepiandrosterone sulphate (DHEAS), sex hormone binding globulin (SHBG), the oestrogens, oestrone and oestradiol, luteinizing hormone (LH) and prolactin. The ratio of the mean hormone concentration in prostate cancer cases to that of controls (and its 95% confidence interval (CI)) was calculated for each study, and the results summarized by calculating the weighted average of the log ratios. No differences in the average concentrations of the hormones were found between prostate cancer cases and controls, with the possible exception of A-diol-g which exhibited a 5% higher mean serum concentration among cases relative to controls (ratio 1.05, 95% CI 1.00-1.11), based on 644 cases and 1048 controls. These data suggest that there are no large differences in circulating hormones between men who subsequently go on to develop prostate cancer and those who remain free of the disease. Further research is needed to substantiate the small difference found in A-diol-g concentrations between prostate cancer cases and controls

Androgens and the breast

Androgens have important physiological effects in women while at the same time they may be implicated in breast cancer pathologies. However, data on the effects of androgens on mammary epithelial proliferation and/or breast cancer incidence are not in full agreement. We performed a literature review evaluating current clinical, genetic and epidemiological data regarding the role of androgens in mammary growth and neoplasia. Epidemiological studies appear to have significant methodological limitations and thus provide inconclusive results. The study of molecular defects involving androgenic pathways in breast cancer is still in its infancy. Clinical and nonhuman primate studies suggest that androgens inhibit mammary epithelial proliferation and breast growth while conventional estrogen treatment suppresses endogenous androgens. Abundant clinical evidence suggests that androgens normally inhibit mammary epithelial proliferation and breast growth. Suppression of androgens using conventional estrogen treatment may thus enhance estrogenic breast stimulation and possibly breast cancer risk. Addition of testosterone to the usual hormone therapy regimen may diminish the estrogen/progestin increase in breast cancer risk but the impact of this combined use on mammary gland homeostasis still needs evaluation