Lipoxins attenuate renal fibrosis by inducing let-7c and suppressing TGFβR1

Lipoxins, which are endogenously produced lipid mediators, promote the resolution of inflammation, and may inhibit fibrosis, suggesting a possible role in modulating renal disease. Here, lipoxin A4 (LXA4) attenuated TGF-ß1-induced expression of fibronectin, N-cadherin, thrombospondin, and the notch ligand jagged-1 in cultured human proximal tubular epithelial (HK-2) cells through a mechanism involving upregulation of the microRNA let-7c. Conversely, TGF-ß1 suppressed expression of let-7c. In cells pretreated with LXA4, upregulation of let-7c persisted despite subsequent stimulation with TGF-ß1. In the unilateral ureteral obstruction model of renal fibrosis, let-7c upregulation was induced by administering an LXA4 analog. Bioinformatic analysis suggested that targets of let-7c include several members of the TGF-ß1 signaling pathway, including the TGF-ß receptor type 1. Consistent with this, LXA4-induced upregulation of let-7c inhibited both the expression of TGF-ß receptor type 1 and the response to TGF-ß1. Overexpression of let-7c mimicked the antifibrotic effects of LXA4 in renal epithelia; conversely, anti-miR directed against let-7c attenuated the effects of LXA4. Finally, we observed that several let-7c target genes were upregulated in fibrotic human renal biopsies compared with controls. In conclusion, these results suggest that LXA4-mediated upregulation of let-7c suppresses TGF-ß1-induced fibrosis and that expression of let-7c targets is dysregulated in human renal fibrosis.

Diabetic retinopathy: morphometric analysis of basement membrane thickening of capillaries in different retinal layers within arterial and venous environments

AIMS: To assess quantitatively variations in the extent of capillary basement membrane (BM) thickening between different retinal layers and within arterial and venous environments during diabetes. METHODS: One year after induction of experimental (streptozotocin) diabetes in rats, six diabetic animals together with six age-matched control animals were sacrificed and the retinas fixed for transmission electron microscopy (TEM). Blocks of retina straddling the major arteries and veins in the central retinal were dissected out, embedded in resin, and sectioned. Capillaries in close proximity to arteries or veins were designated as residing in either an arterial (AE) or a venous (VE) environment respectively, and the retinal layer in which each capillary was located was also noted. The thickness of the BM was then measured on an image analyser based two dimensional morphometric analysis system. RESULTS: In both diabetics and controls the AE capillaries had consistently thicker BMs than the VE capillaries. The BMs of both AE and VE capillaries from diabetics were thicker than those of capillaries in the corresponding retinal layer from the normal rats (p <or = 0.005). Also, in normal AE and VE capillaries and diabetic AE capillaries the BM in the nerve fibre layer (NFL) was thicker than that in either the inner (IPL) or outer (OPL) plexiform layers (p <or = 0.001). However, in diabetic VE capillaries the BMs of capillaries in the NFL were thicker than those of capillaries in the IPL (p <or = 0.05) which, in turn, had thicker BMs than capillaries in the OPL (p <or = 0.005). CONCLUSIONS: The variation in the extent of capillary BM thickening between different retinal layers within AE and VE environments may be related to differences in levels of oxygen tension and oxidative stress in the retina around arteries compared with that around veins.

The continuous erythropoietin receptor activator (C.E.R.A.) corrects anemia at extended administration intervals in patients with chronic kidney disease not on dialysis:results of a phase II study

This study was designed to assess the potential of the continuous erythropoietin receptor activator (C.E.R.A.) to correct anemia at extended administration intervals in erythropoiesis-stimulating agent-naīve patients with chronic kidney disease (CKD) not on dialysis and to determine its optimal starting dose.

SMAD inhibition attenuates epithelial to mesenchymal transition by primary keratinocytes in vitro

Epithelial to mesenchymal transition (EMT) is a process whereby epithelial cells undergo transition to a mesenchymal phenotype and contribute directly to fibrotic disease. Recent studies support a role for EMT in cutaneous fibrotic diseases including scleroderma and hypertrophic scarring, though there is limited data on the cytokines and signalling mechanisms regulating cutaneous EMT. We investigated the ability of TGF-β and TNF-α, both over-expressed in cutaneous scleroderma and central mediators of EMT in other epithelial cell types, to induce EMT in primary keratinocytes and studied the signalling mechanisms regulating this process. TGF-β induced EMT in normal human epidermal keratinocytes (NHEK cells) and this process was enhanced by TNF-α. EMT was characterised by changes in morphology, proteome (down-regulation of E-cadherin and Zo-1, and up-regulation of vimentin and fibronectin), MMP secretion and COL1α1 mRNA expression. TGF-β and TNF-α in combination activated SMAD and p38 signalling in NHEK cells. P38 inhibition with SB203580 partially attenuated EMT, whereas SMAD inhibition using SB431542 significantly inhibited EMT and also reversed established EMT. These data highlight the retained plasticity of adult keratinocytes and support further studies of EMT in clinically relevant in vivo models of cutaneous fibrosis, and investigation of SMAD inhibition as a potential therapeutic intervention. This article is protected by copyright. All rights reserved.

Explaining the Stunted Rise of Macroprudential Regulatory Philosophies

In the aftermath of the financial crash of 2008, policy makers operating in international financial regulatory networks discovered macroprudential regulation (MPR), but macroprudential regulation has had a stunted or arrested development that can be explained with reference to five factors that are recounted in this article

Building Information Modelling Energy Performance Assessment on Domestic Dwellings: A Comparative Study

Building Information Modelling (BIM) is growing in pace, not only in design and construction stages, but also in the analysis of facilities throughout their life cycle. With this continued growth and utilisation of BIM processes, comes the possibility to adopt such procedures, to accurately measure the energy efficiency of buildings, to accurately estimate their energy usage. To this end, the aim of this research is to investigate if the introduction of BIM Energy Performance Assessment in the form of software analysis, provides accurate results, when compared with actual energy consumption recorded. Through selective sampling, three domestic case studies are scrutinised, with baseline figures taken from existing energy providers, the results scrutinised and compared with calculations provided from two separate BIM energy analysis software packages. Of the numerous software packages available, criterion sampling is used to select two of the most prominent platforms available on the market today. The two packages selected for scrutiny are Integrated Environmental Solutions - Virtual Environment (IES-VE) and Green Building Studio (GBS). The results indicate that IES-VE estimated the energy use in region of ±8% in two out of three case studies while GBS estimated usage approximately ±5%. The findings indicate that the introduction of BIM energy performance assessment, using proprietary software analysis, is a viable alternative to manual calculations of building energy use, mainly due to the accuracy and speed of assessing, even the most complex models. Given the surge in accurate and detailed BIM models and the importance placed on the continued monitoring and control of buildings energy use within today’s environmentally conscious society, this provides an alternative means by which to accurately assess a buildings energy usage, in a quick and cost effective manner.

Abstract 1905: Defining a therapeutic classification of breast cancer by actionable targets

Breast cancer remains a frequent cause of female cancer death despite the great strides in elucidation of biological subtypes and their reported clinical and prognostic significance. We have defined a general cohort of breast cancers in terms of putative actionable targets, involving growth and proliferative factors, the cell cycle, and apoptotic pathways, both as single biomarkers across a general cohort and within intrinsic molecular subtypes.

We identified 293 patients treated with adjuvant chemotherapy. Additional hormonal therapy and trastuzumab was administered depending on hormonal and HER2 status respectively. We performed immunohistochemistry for ER, PR, HER2, MM1, CK5/6, p53, TOP2A, EGFR, IGF1R, PTEN, p-mTOR and e-cadherin. The cohort was classified into luminal (62%) and non-luminal (38%) tumors as well as luminal A (27%), luminal B HER2 negative (22%) and positive (12%), HER2 enriched (14%) and triple negative (25%). Patients with luminal tumors and co-overexpression of TOP2A or IGF1R loss displayed worse overall survival (p=0.0251 and p=0.0008 respectively). Non-luminal tumors had much greater heterogeneous expression profiles with no individual markers of prognostic significance. Non-luminal tumors were characterised by EGFR and TOP2A overexpression, IGF1R, PTEN and p-mTOR negativity and extreme p53 expression.

Our results indicate that only a minority of intrinsic subtype tumors purely express single novel actionable targets. This lack of pure biomarker expression is particular prevalent in the triple negative subgroup and may allude to the mechanism of targeted therapy inaction and myriad disappointing trial results. Utilising a combinatorial biomarker approach may enhance studies of targeted therapies providing additional information during design and patient selection while also helping decipher negative trial results.

Protein expression differences between lung adenocarcinoma and squamous cell carcinoma with brain metastasis

AIM: We investigated tissue biomarkers in non-small cell lung cancer (NSCLC) to find indicators of brain metastasis and peritumoral brain edema.

PATIENTS AND METHODS: Fifty-two cases were studied out of which 26 had corresponding brain metastatic tissue. Clinicopathological characteristics of tumors were correlated with biomarkers of cell adhesion, cell growth, cell cycle and apoptosis regulation that were previously immunohistochemically studied but never analyzed separately according to histological subgroups, gender and smoking history.

RESULTS: Increased collagen XVII in adenocarcinoma (ADC) and increased caspase-9, CD44v6, and decreased cellular apoptosis susceptibility protein (CAS) and Ki-67 in squamous cell carcinoma (SCC) correlated significantly with brain metastasis. Increased β-catenin, E-cadherin and decreased caspase-9 expression in primary SCC, and decreased CD44v6 expression in brain metastatic SCC tissues showed a significant correlation with the extent of peritumoral brain edema. Positive correlation between smoking and biomarker expression could be observed in metastatic ADCs with p16 and caspase-8, while-negative correlation was found in SCC without brain metastasis with caspase-3, and in SCC with brain metastasis with p27.

CONCLUSION: Our results highlight the importance of separate analysis of biomarker expression in histological subtypes of NSCLC.

Diabetic retinopathy:morphometric analysis of basement membrane thickening of capillaries in different retinal layers within arterial and venous environments

AIMS: To assess quantitatively variations in the extent of capillary basement membrane (BM) thickening between different retinal layers and within arterial and venous environments during diabetes.

METHODS: One year after induction of experimental (streptozotocin) diabetes in rats, six diabetic animals together with six age-matched control animals were sacrificed and the retinas fixed for transmission electron microscopy (TEM). Blocks of retina straddling the major arteries and veins in the central retinal were dissected out, embedded in resin, and sectioned. Capillaries in close proximity to arteries or veins were designated as residing in either an arterial (AE) or a venous (VE) environment respectively, and the retinal layer in which each capillary was located was also noted. The thickness of the BM was then measured on an image analyser based two dimensional morphometric analysis system.

RESULTS: In both diabetics and controls the AE capillaries had consistently thicker BMs than the VE capillaries. The BMs of both AE and VE capillaries from diabetics were thicker than those of capillaries in the corresponding retinal layer from the normal rats (p < or = 0.005). Also, in normal AE and VE capillaries and diabetic AE capillaries the BM in the nerve fibre layer (NFL) was thicker than that in either the inner (IPL) or outer (OPL) plexiform layers (p < or = 0.001). However, in diabetic VE capillaries the BMs of capillaries in the NFL were thicker than those of capillaries in the IPL (p < or = 0.05) which, in turn, had thicker BMs than capillaries in the OPL (p < or = 0.005).

CONCLUSIONS: The variation in the extent of capillary BM thickening between different retinal layers within AE and VE environments may be related to differences in levels of oxygen tension and oxidative stress in the retina around arteries compared with that around veins.

Molecular markers for predicting recurrence, progression and outcomes of bladder cancer (do the poster boys need new posters

Purpose of review
Molecular markers for bladder cancer recurrence and
progression continue to drive many research programmes.
Translating the laboratory findings into the clinical environment
where these markers are used in clinical decision making has
proved problematic. In the clinical arena, stage and grade are
still the main focus for decisions about patient management.
There is however an evolution in bladder cancer research from
single-marker/single-pathway research to a more global
assessment of the tumour cell with DNA microarrays and
proteomics.
Recent findings
In the last year, DNA microarray assessment has revealed
several interesting molecular markers such as p33ING1 and
DEK. Parallel ‘conventional’ single-pathway research has
focused on new novel markers such as HER2/neu, survivin and
matrix metalloproteinase 2 (MMP-2). Molecular markers that
have a long-standing association with bladder cancer
progression such as p53, E-cadherin and Ki-67 have been
reviewed by both single-marker studies and by microarray
studies and their status remains important.
Summary
It is an exciting time in the molecular biology research of bladder
cancer as the focus changes to assess the global genetic and
protein expression within tumour cells. From such a wealth of
information it is likely that molecular markers will make the
translation from benchside to bedside.

Protein deregulation associated with breast cancer metastasis

Breast cancer is one of the most prevalent malignancies worldwide. It consists of a group of tumor cells that have the ability to grow uncontrollably, overcome replicative senescence (tumor progression) and metastasize within the body. Metastases are processes that consist of an array of complex gene dysregulation events. Although these processes are still not fully understood, the dysregulation of a number of key proteins must take place if the tumor cells are to disseminate and metastasize. It is now widely accepted that future effective and innovative treatments of cancer metastasis will have to encompass all the major components of malignant transformation. For this reason, much research is now being carried out into the mechanisms that govern the malignant transformation processes. Recent research has identified key genes involved in the development of metastases, as well as their mechanisms of action. A detailed understanding of the encoded proteins and their interrelationship generates the possibility of developing novel therapeutic approaches. This review will focus on a select group of proteins, often deregulated in breast cancer metastasis, which have shown therapeutic promise, notably, EMT, E-cadherin, Osteopontin, PEA3, Transforming Growth Factor Beta (TGF-β) and Ran.

Alterations in beta-catenin expression and localization in prostate cancer

BACKGROUND: Wnt signaling is thought to be important in prostate cancer, in part because proteins such as beta-catenin can also affect androgen receptor signaling. beta-Catenin forms a cell adhesion complex with E-cadherin raising the possibility that loss of expression or a change in beta-catenin distribution in the cell could also alter downstream signaling, decreased inter-cellular adhesion and the promotion of metastasis. A number of studies have reported the altered expression and/or localization of beta-catenin as a biomarker in prostate cancer.

METHODS: Tissue microarrays comprised of BPH and low, moderate and high-grade prostate cancer (n=77) were assessed for beta-catenin expression and distribution using immunohistochemistry. Staining was also performed on a tissue microarray containing tissue from patients before and after hormone manipulation. The effects of fixation and different antibodies was assessed on fixed LNCaP cell pellets and small prostate tissue microarrays.

RESULTS: We have observed increased beta-catenin expression in only high Gleason score (>7) prostate cancer. A nuclear re-distribution of beta-catenin has previously been reported. We noted nuclear beta-catenin in benign prostatic hyperplasia and a gradual loss in nuclear distribution with increasing Gleason grade. We found no evidence for an alteration in beta-catenin expression or re-distribution with hormone ablation. Altered fixation, antibodies and antibody concentration did affect the intensity and specificity of staining.

CONCLUSIONS: A loss of nuclear beta-catenin is the most consistent feature in prostate cancer rather than absolute levels of expression. We also suggest that variation in immunohistochemical protocols may explain variations in the reported literature.

Separation Science and Technology - Theory

I have completed 80% of a teaching text book (text and graphics) on Separation Science and Technology - Theory. The book's content is what I've learned over many years of practice and teaching with an emphasis on clarifying and explaining the nuances within the theories associated with various practical approaches to chemical and biochemical separations.

The book is divided into self-contained Chapters with many worked examples and practice questions. It very much aligns with my teaching on CHM3005D, CHM2010, CHM2007 and is ideal for PMY8105 and the new proposed MSci in Analytical Chemistry Programme. The book brings together diverse material in single space and will be a valuable pedagogical resource for the teaching of this key discipline within QUB and elsewhere.

Expression of proteins associated with hypoxia and Wnt pathway activation is of prognostic significance in hepatocellular carcinoma

In the development and progression of hepatocellular carcinoma, tumor hypoxia plays an important role, as does activation of the Wnt pathway. The aim of this study was to characterize the expression and interrelationship between hypoxia and Wnt-pathway-associated proteins as prognostic factors for hepatocellular carcinoma. Expression of HIF-1α, CA-IX, E-cadherin, β-catenin, and Ki-67 was assessed by immunohistochemistry in 179 primary hepatocellular carcinoma cases. Univariate and multivariate analyses were performed to assess the relationship between the clinicopathological factors, protein expression, overall survival (OS), and recurrence-free survival (RFS). By univariate analysis, tumor stage, size, satellitosis, and vascular invasion were confirmed as prognostic factors for worse OS and RFS. High expression of HIF-1α, CA-IX, β-catenin, Ki-67, and E-cadherin was observed in 60, 15, 64, 8, and 64 % of tumors, respectively, and this was significantly associated with poor OS. CA-IX, HIF-1α, and E-cadherin were independent predictors of poor prognosis. We stratified 169 patients into four groups according to the expression level of hypoxia and Wnt pathway markers. The group with high expression of both hypoxia and Wnt-pathway-associated proteins showed worst OS. The poor survival of this group was also significant in patients with early stage disease and tumor size of less than 5 cm (p < 0.05). We identified a subgroup of hepatocellular carcinoma patients with high expression of both hypoxia and Wnt pathway proteins and found this predictive of poor survival. The therapeutic options for this group might need to be revisited.