The effects of prolyl hydroxylase inhibition during and post, hypoxia, oxygen glucose deprivation and oxidative stress, in isolated rat hippocampal slices.

The contributions of hypoxia and oxidative stress to the pathophysiology of acute ischemic stroke are well established and can lead to disruptions in synaptic signaling. Hypoxia and oxidative stress lead to the neurotoxic overproduction of reactive oxygen species (ROS) and the stabilization of hypoxia inducible factors (HIF). Compounds such as prolyl-4-hydroxylase domain enzyme inhibitors (PHDIs) have been shown to have a preconditioning and neuroprotective effect against ischemic insults such as hypoxia, anoxia, oxygen glucose deprivation (OGD) or H2O2. Therefore, this study explored the effects of two PHDIs, JNJ-42041935 (10 µM) and roxadustat (100 µM) on cell viability using organotypic hippocampal slice cultures. We also assessed the effects of these compounds on synaptic transmission during and post hypoxia, OGD and H2O2 application in isolated rat hippocampal slices using field recording electrophysiological techniques and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor subunit trafficking using immunohistochemistry. Our organotypic data demonstrated a protective role for both inhibitors, where slices had significantly less cell death post anoxia and OGD compared to controls. We also report a distinct modulatory role for both JNJ-42041935 and roxadustat on fEPSP slope post hypoxia and OGD but not H2O2. In addition, we report that application of roxadustat impaired long-term potentiation, but only when applied post-hypoxia. This inhibitory effect was not reversed with co-application of the cyclin-dependent kinase 5 (CDK-5) inhibitor, roscovitine (10 µM), suggesting a CDK-5 independent synaptic AMPAR trafficking mechanism. Both hypoxia and OGD induced a reduction in synaptic AMPA GluA2 subunits, the OGD effect being reversed by prior treatment with both JNJ-42041935 and roxadustat. These results suggest an important role for PHDs in synaptic signaling and plasticity during episodes of ischemic stress.

Tumour stemness and poor clinical outcomes in haemochromatosis patients with hepatocellular carcinoma.

AIMS: Patients with haemochromatosis (HFE) are known to have an increased risk of developing hepatocellular carcinoma (HCC). Available data are conflicting on whether such patients have poorer prognosis, and there is lack of data regarding the biology of HFE-HCC. We compared the course of HFE-HCC with a matched non-HFE-HCC control group and examined tumour characteristics using immunohistochemistry. METHODS: In this tertiary care-based retrospective analysis, 12 patients with HFE and 34 patients with alcohol/non-alcoholic steatohepatitis who underwent initially successful curative HCC therapy with ablation or resection were identified from our registry. Time to tumour progression was compared. Resected liver tissue from a separate cohort of 11 matched patients with HFE-HCC and without HFE-HCC was assessed for the expression of progenitor and epithelial-mesenchymal transition markers using immunohistochemistry. RESULTS: The median follow-up was 24.39 and 24.28 months for patients with HFE-HCC and those without HFE-HCC, respectively (p>0.05). The mean time to progression was shorter in the HFE group compared with the non-HFE group (12.87 months vs 17.78 months; HR 3.322, p<0.05). Patients with HFE-HCC also progressed to more advanced disease by the end of follow-up (p<0.05). Immunohistochemical analysis of matched HFE-HCC and non-HFE-HCC explants demonstrated increased expression of the cancer stem cell markers EpCAM (epithelial cell adhesion molecule) and EpCAM/SALL4 (spalt-like transcription factor 4) coexpression in HFE-HCC specimens (p<0.05). There was a high frequency of combined tumour subtypes within the HFE cohort. CONCLUSIONS: This study demonstrates that the clinical course of patients with HFE-HCC is more aggressive and provides the first data indicating that their tumours have increased expression of progenitor markers. These findings suggest patients with HFE-HCC may need to be considered for transplant at an earlier stage.

Suppressive effects of the obese tumor microenvironment on CD8 T cell infiltration and effector function.

Obesity is one of the leading preventable causes of cancer; however, little is known about the effects of obesity on anti-tumor immunity. Here, we investigated the effects of obesity on CD8 T cells in mouse models and patients with endometrial cancer. Our findings revealed that CD8 T cell infiltration is suppressed in obesity, which was associated with a decrease in chemokine production. Tumor-resident CD8 T cells were also functionally suppressed in obese mice, which was associated with a suppression of amino acid metabolism. Similarly, we found that a high BMI negatively correlated with CD8 infiltration in human endometrial cancer and that weight loss was associated with a complete pathological response in six of nine patients. Moreover, immunotherapy using anti-PD-1 led to tumor rejection in lean and obese mice and partially restored CD8 metabolism and anti-tumor immunity. These findings highlight the suppressive effects of obesity on CD8 T cell anti-tumor immunity, which can partially be reversed by weight loss and/or immunotherapy.

Immunological aspects of ovarian follicle ovulation and corpus luteum formation in cattle.

Ovulation has been described as an inflammatory event, characterized by an influx of leukocytes into the ovulatory follicle and changes in the expression profile of immune factors in both the theca and granulosa tissue layers. Since information on this process is limited in cattle, our objective was to elucidate the contribution of the immune system to dominant follicle luteinization, ovulation and corpus luteum (CL) formation in cattle. Beef heifers (n = 50) were oestrous synchronized, slaughtered and ovarian follicular or luteal tissue collected during a 96 h window around ovulation. Follicular fluid cytokine concentration, temporal immune cell infiltration and inflammatory status were determined by Luminex multiplex analysis, immunohistochemistry and quantitative real-time PCR-analysis, respectively, in pre- and peri-ovulatory follicular tissues. The concentrations of IL10 and VEGF-A were highest in pre-ovulatory and the concentration of CXCL10 was highest in peri-ovulatory follicular fluid samples. The pre and peri-ovulatory follicles play host to a broad repertoire of immune cells, including T-cells, granulocytes and monocytes. Dendritic cells were the most abundant cells in ovulatory follicular and luteal-tissue at all times. The mRNA expression of candidate genes associated with inflammation was highest in pre- and peri-ovulatory tissue, whereas tissue growth and modelling factors were highest in the post-ovulatory follicular and early luteal tissue. In conclusion, ovulation in cattle is characterized by the presence of neutrophils, macrophages and dendritic cells in the ovulatory follicle, reflected in compartmentalized cytokine and growth factor expression. These findings indicate a tightly regulated sterile inflammatory response to the LH surge in the ovulatory follicle which is rapidly resolved in advance of CL formation.

Inhibition of Serum Response Factor Improves Response to Enzalutamide in Prostate Cancer.

Castrate-resistant prostate cancer (CRPC) is challenging to treat with the androgen receptor (AR), the main target and key focus of resistance. Understanding the mechanisms of AR interaction with co-regulators will identify new therapeutic targets to overcome AR resistance mechanisms. We previously identified the serum response factor (SRF) as a lead target in an in vitro model of CRPC and showed that SRF expression in tissues of CRPC patients was associated with shorter survival. Here, we tested SRF inhibition in vitro and in vivo to assess SRF as a potential target in CRPC. Inhibition of SRF with the small-molecule inhibitor CCG1423 resulted in enhanced response to enzalutamide in vitro and reduced tumour volume of LuCaP 35CR, a CRPC patient-derived xenograft model. Nuclear localisation of AR post-CCG1423 was significantly decreased and was associated with decreased α-tubulin acetylation in vitro and decreased prostate specific antigen (PSA) levels in vivo. SRF immunoreactivity was tested in metastatic tissues from CRPC patients to investigate its role in enzalutamide response. Kaplan-Meier curves showed that high SRF expression was associated with shorter response to enzalutamide. Our study supports the use of SRF inhibitors to improve response to enzalutamide.

Characterization of the renal cortical transcriptome following Roux-en-Y gastric bypass surgery in experimental diabetic kidney disease.

INTRODUCTION: Roux-en-Y gastric bypass surgery (RYGB) reduces albuminuria and the long-term incidence of end-stage renal disease in patients with obesity and diabetes. Preclinical modeling in experimental diabetic kidney disease demonstrates that improvements in glomerular structure likely underpin these findings. RESEARCH DESIGN AND METHODS: In adult male Zucker diabetic fatty (ZDF) rats, we profiled the effect of RYGB on weight and metabolic control as well biochemical, structural and ultrastructural indices of diabetic renal injury. Furthermore, we sequenced the renal cortical transcriptome in these rats and used bioinformatic pathway analyses to characterize the transcriptional alterations governing the renal reparative response to RYGB. RESULTS: In parallel with improvements in weight and metabolic control, RYGB reduced albuminuria, glomerulomegaly, podocyte stress and podocyte foot process effacement. Pathway analysis of RYGB-induced transcriptomic changes in the renal cortex highlighted correction of disease-associated alterations in fibrosis, inflammation and biological oxidation pathways. RYGB reversed disease-associated changes in the expression of transforming growth factor (TGF)-ß superfamily genes that strongly correlated with improvements in structural measures of glomerulopathy. CONCLUSIONS: Improved glomerular structure in ZDF rats following RYGB is underpinned by pathway level changes, including interruption of the TGF-ß-driven early profibrotic programme. Our data provide an important layer of experimental support for clinical evidence demonstrating that RYGB arrests renal damage in patients with obesity and type 2 diabetes.

Abatacept reduces synovial regulatory T-cell expression in patients with psoriatic arthritis.

BACKGROUND: The aim was to study changes in immunohistochemical expression markers of synovial and skin inflammation, clinical outcomes and magnetic resonance imaging (MRI) scores with abatacept treatment in patients with psoriatic arthritis (PsA). METHODS: Biological-treatment-naïve PsA patients with active disease including synovitis of a knee were enrolled in this single-centre, crossover study. Patients were randomised to receive intravenous abatacept 3 mg/kg of body weight or placebo infusion on day 1, 15 and 29; thereafter abatacept 10 mg/kg of body weight was administered every 28 days for 5 months. Clinical data were collected at each visit. Synovial biopsy of the involved knee was obtained at baseline and 2 and 6 months. MRI of the same knee and skin biopsy was performed prior to arthroscopy. RESULTS: Fifteen patients were recruited. Significant improvements in the joint-related measures were observed; 90% were European League Against Rheumatism criteria responders and 30% achieved psoriasis area severity index (PASI)50 at 6 months. Reduction in synovitis (P = 0.016) and vascularity (P = 0.039) macroscopic scores consistent with decrease in total MRI score (P = 0.016) were noticed. Abatacept decreased the immunohistological expression of FOXP3+ cells (P = 0.027), specifically the expression of CD4+FOXP3+ regulatory T cells (Tregs) (P = 0.008) in the synovium over 6 months. There was no significant clinical or immunohistological change in any of the skin measures. CONCLUSION: This is the first study assessing synovial and psoriatic skin immunpathological changes following abatacept treatment in PsA. Reduction in Treg expression in the synovium but not in the psoriatic lesion suggests abnormal Treg function in PsA with differential suppressive capacity in the synovium compared to the lesional skin. The results of this study demonstrate that abatacept 10 mg/kg of body weight might be an effective treatment option for joint disease in patients with PsA. TRIAL REGISTRATION: Irish Health Products Regulatory Authority. TRIAL REGISTRATION NUMBER: CT 900/489/1 - Abatacept (case number: 2077284, EudraCT Number: 2009-017525-19, Protocol number: 77777). Registered on 12 March 2010.

Effect of anaesthetic technique on immune cell infiltration in breast cancer: a follow-up pilot analysis of a prospective, randomised, investigator-masked study.

BACKGROUND: Live animal studies using an inoculation model of breast cancer indicate that anaesthetic drugs and techniques differentially affect cancer metastasis, inversely related to Natural Killer (NK) cell and T lymphocyte levels. Clinical histological studies demonstrate that the distribution of these immune cells and macrophages in intra-tumoral cancer tissue can predict prognosis and response to therapy. No study has evaluated whether the anaesthetic technique influences human breast cancer immune cell infiltration. MATERIALS AND METHODS: Excised breast cancer specimens from patients previously enrolled in an ongoing, prospective, randomised trial (NCT00418457) investigating the effect of anaesthetic technique on long-term breast cancer outcome were immunohistochemically stained to enable a colour deconvolution technique to summate marked immune cell infiltration: CD56 (NK cells), CD4 (T helper cells), CD8 (T suppressor cells) and CD68 (macrophages). Patients were randomised to receive either a propofol-paravertebral anaesthetic with continuing analgesia (PPA, n=12) or a balanced general anaesthesia with opioid analgesia (GA, n=16) for 24 h postoperatively. Investigators were masked to group allocation. RESULTS: Normalised positive intensity values, (median (interquartile range (IQR)), for CD56 were lower in GA121 (116-134) versus 136 (132-142), p=0.015. CD4 was also lower in GA10.9 (5.5-27.8) versus PPA 19.7 (14.4-83.5), p=0.03 but CD8 5.5 (4.0-9.75) versus 13.0 (5.0-14.5) respectively, p=0.24 and CD 68 infiltration 5.8 (3.25-8.75) versus 8.0 (3.0-8.75), p=0.74 were not significantly different. CONCLUSION: PPA induces increased levels of NK and T helper cell infiltration into breast cancer tissue compared with GA but not T suppressor cells or macro phages. This is consistent with the hypothesis that the anaesthetic technique may affect perioperative immune function conducive to resisting breast cancer recurrence and metastasis.

Real-time quantitative reverse transcriptase-polymerase chain reaction analysis of melanoma progression-associated genes.

BACKGROUND: Melanoma is an aggressive disease that spreads quickly and is resistant to most therapeutic agents. In an effort to provide insight into the molecular basis of melanoma progression, the expression of 94 genes in 20 metastatic melanomas using a high-throughput real-time quantitative RT-PCR assay was analysed. MATERIALS AND METHODS: A TaqMan low density array (LDA) was designed containing probes/primers directed towards a cohort of genes previously found to be differentially expressed in an isogenic cell line model of melanoma progression. For each sample, cDNA was prepared and added to the quantitative assay. The resulting data were then analysed for correlations with clinical data. RESULTS: Clustering analysis divided the melanomas into two major subgroups based on gene expression patterns. When analysed individually, several genes were associated with overall survival, depth and type of the primary tumour. CONCLUSION: We have identified a selection of genes linked to melanoma progression and patient outcome.