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1.
Immunol Cell Biol ; 102(5): 321-325, 2024.
Article in English | MEDLINE | ID: mdl-38403985

ABSTRACT

Monash Sensory Science is a scientific outreach initiative specifically tailored to members of the community who are blind, have low vision and have diverse needs. The purpose of this initiative is to showcase Australian science and encourage greater participation in science from these often-overlooked communities. This article presents our experience in establishing Monash Sensory Science at Monash University and inspiring other institutions to launch similar outreach events.


Subject(s)
Vision, Low , Humans , Australia , Blindness
2.
Front Aging ; 4: 1260502, 2023.
Article in English | MEDLINE | ID: mdl-37780865

ABSTRACT

Functional decline with age contributes significantly to the burden of disease in developed countries. There is growing interest in the development of therapeutic interventions which slow or even reverse aging. Time and cost constraints prohibit the testing of a large number of interventions for health and lifespan extension in model organisms. Cell-based models of aging could enable high throughput testing of potential interventions. Despite extensive reports in the literature of cell properties that correlate with donor age, few are robustly observed across different laboratories. This casts doubt on the extent that aging signatures are captured in cultured cells. We tested molecular changes previously reported to correlate with donor age in peripheral blood mononuclear cells (PBMCs) and evaluated their suitability for inclusion in a panel of functional aging measures. The tested measures spanned several pathways implicated in aging including epigenetic changes, apoptosis, proteostasis, and intracellular communication. Surprisingly, only two markers correlated with donor age. DNA methylation age accurately predicted donor age confirming this is a robust aging biomarker. Additionally, the apoptotic marker CD95 correlated with donor age but only within subsets of PBMCs. To demonstrate cellular rejuvenation in response to a treatment will require integration of multiple read-outs of cell function. However, building a panel of measures to detect aging in cells is challenging and further research is needed to identify robust predictors of age in humans.

3.
Nutrients ; 15(19)2023 Sep 25.
Article in English | MEDLINE | ID: mdl-37836428

ABSTRACT

Bitter taste receptors (Tas2rs in mice) detect bitterness, a warning signal for toxins and poisons, and are expressed in enteroendocrine cells. We tested the hypothesis that Tas2r138 and Tas2r116 mRNAs are modulated by microbiota alterations induced by a long-term high-fat diet (HFD) and antibiotics (ABX) (ampicillin and neomycin) administered in drinking water. Cecum and colon specimens and luminal contents were collected from C57BL/6 female and male mice for qRT-PCR and microbial luminal 16S sequencing. HFD with/without ABX significantly increased body weight and fat mass at 4, 6, and 8 weeks. Tas2r138 and Tas2r116 mRNAs were significantly increased in mice fed HFD for 8 weeks vs. normal diet, and this increase was prevented by ABX. There was a distinct microbiota separation in each experimental group and significant changes in the composition and diversity of microbiome in mice fed a HFD with/without ABX. Tas2r mRNA expression in HFD was associated with several genera, particularly with Akkermansia, a Gram-negative mucus-resident bacterium. These studies indicate that luminal bacterial composition is affected by sex, diet, and ABX and support a microbial dependent upregulation of Tas2rs in HFD-induced obesity, suggesting an adaptive host response to specific diet-induced dysbiosis.


Subject(s)
Gastrointestinal Microbiome , Microbiota , Male , Female , Mice , Animals , Diet, High-Fat/adverse effects , Taste , Up-Regulation , Mice, Inbred C57BL , Obesity/metabolism , Cecum/microbiology , Dysbiosis/microbiology
4.
STAR Protoc ; 4(1): 101961, 2023 03 17.
Article in English | MEDLINE | ID: mdl-36633948

ABSTRACT

Tertiary lymphoid structures (TLSs) are ectopic lymphoid aggregates that can develop within or adjacent to tumors, but protocols that can accurately identify and characterize TLSs are lacking. Here, we present a protocol for the in situ interrogation and characterization of TLSs in human and murine tissue sections using Opal™-tyramide signal amplification multiplex immunohistochemistry. This protocol enables simultaneous detection of up to 7 markers (6 antigens and a DAPI counterstain). We also describe a grading system to identify immature and mature TLSs.


Subject(s)
Neoplasms , Tertiary Lymphoid Structures , Humans , Mice , Animals , Tertiary Lymphoid Structures/pathology , Immunohistochemistry , Neoplasms/pathology
5.
Methods Mol Biol ; 2593: 307-316, 2023.
Article in English | MEDLINE | ID: mdl-36513940

ABSTRACT

Multiplex immunohistochemistry (mIHC) facilitates the simultaneous detection of various immune cell markers on a single tissue section. Here, we describe a protocol for an mIHC staining workflow using specific antibodies against CD4, CD8α, FOXP3, and B220 to identify distinct lymphocyte populations including T and B cells. This staining strategy can be adapted to include other cell markers to evaluate the immune contexture in murine tissues.


Subject(s)
Antibodies , Mice , Animals , Immunohistochemistry , Staining and Labeling , Biomarkers
6.
Antimicrob Resist Infect Control ; 11(1): 160, 2022 12 18.
Article in English | MEDLINE | ID: mdl-36529742

ABSTRACT

BACKGROUND: In neutropenic patients, bloodstream infections (BSI) significantly contribute to morbidity and mortality. Appropriate empirical antibiotic therapy (EAT) of BSI is essential, at the same time overconsumption of very broad-spectrum antibiotics should be avoided. We investigated: (1) whether surveillance cultures can predict BSI with third-generation cephalosporin -resistant Enterobacterales and Pseudomonas aeruginosa (3GC-R), (2) the effect of inappropriate empirical antimicrobial therapy (IEAT) on clinical outcome and (3) the potential reduction of carbapenem use when using surveillance cultures to guide therapy. METHODS: Retrospective study of adult patients with haematological malignancies with febrile episodes during chemotherapy-induced high-risk neutropenia in whom surveillance cultures were collected weekly. IEAT was defined as the absence of in vitro susceptibility of blood-isolates to the administered EAT. Clinical outcome (ICU admission and death) was evaluated within 30 days. RESULTS: A total of 673 febrile episodes occurred among 372 high-risk neutropenic patients. BSI was present in 20.1% (135/673), of which 25.9% (35/135) were due to Enterobacterales and P. aeruginosa. Of these, 17/35 were 3GC-R and 70.6% (12/17) were preceded by 3GC-R colonization. Negative predictive value of surveillance cultures for 3GC-R BSI was 99.1%. IEAT due to (3GC-R) BSI was not significantly associated with clinical outcome. Using surveillance cultures to guide EAT could potentially reduce carbapenem use by 82.8%, when compared to standard EAT with carbapenem. CONCLUSIONS: This retrospective analysis shows that in patients with high-risk neutropenia, surveillance cultures can potentially reduce the use of carbapenems with infrequent IEAT for 3GC-R BSI and no negative impact on clinical outcome.


Subject(s)
Anti-Infective Agents , Bacteremia , Neutropenia , Sepsis , Adult , Humans , Retrospective Studies , Bacteremia/epidemiology , Anti-Infective Agents/therapeutic use , Carbapenems/therapeutic use , Carbapenems/pharmacology , Pseudomonas aeruginosa , Sepsis/epidemiology
7.
Cell Death Dis ; 13(9): 777, 2022 09 08.
Article in English | MEDLINE | ID: mdl-36075907

ABSTRACT

Understanding prostate cancer onset and progression in order to rationally treat this disease has been critically limited by a dire lack of relevant pre-clinical animal models. We have generated a set of genetically engineered mice that mimic human prostate cancer, initiated from the gland epithelia. We chose driver gene mutations that are specifically relevant to cancers of young men, where aggressive disease poses accentuated survival risks. An outstanding advantage of our models are their intact repertoires of immune cells. These mice provide invaluable insight into the importance of immune responses in prostate cancer and offer scope for studying treatments, including immunotherapies. Our prostate cancer models strongly support the role of tumour suppressor p53 in functioning to critically restrain the emergence of cancer pathways that drive cell cycle progression; alter metabolism and vasculature to fuel tumour growth; and mediate epithelial to mesenchymal-transition, as vital to invasion. Importantly, we also discovered that the type of p53 alteration dictates the specific immune cell profiles most significantly disrupted, in a temporal manner, with ramifications for disease progression. These new orthotopic mouse models demonstrate that each of the isogenic hotspot p53 amino acid mutations studied (R172H and R245W, the mouse equivalents of human R175H and R248W respectively), drive unique cellular changes affecting pathways of proliferation and immunity. Our findings support the hypothesis that individual p53 mutations confer their own particular oncogenic gain of function in prostate cancer.


Subject(s)
Prostatic Neoplasms , Tumor Suppressor Protein p53 , Animals , Carcinogenesis/metabolism , Disease Models, Animal , Humans , Male , Mice , PTEN Phosphohydrolase/genetics , PTEN Phosphohydrolase/metabolism , Prostate/metabolism , Prostatic Neoplasms/metabolism , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism
8.
Cytokine ; 155: 155887, 2022 07.
Article in English | MEDLINE | ID: mdl-35512531

ABSTRACT

Interleukin-36 gamma (IL-36G) is a member of the IL-36 subfamily of cytokines and acts as a potent driver of inflammation. IL-36G has been extensively characterized in the pathogenesis of psoriasis and has been recently described to play roles in wound healing particularly in the gastrointestinal tract. However, the effects of IL-36G during cancer development including gastric cancer remain unexplored. Here, we show that IL-36G induced ERK1/2 activation in AGS, MKN1 and MKN45 human gastric cancer cell lines. Moreover, IL-36G induced colony formation, migration and invasion of these gastric cancer cell lines that was inhibited by the natural antagonist, IL-36 receptor antagonist (RA). Interrogation of TCGA stomach adenocarcinoma patient datasets revealed highly elevated IL-36G gene expression in human gastric cancer compared to normal tissue independent of tumor stage, and high IL-36G expression corresponded with poorer patient survival. Collectively, our results indicate for the first time that IL-36G supports a neoplastic phenotype in human gastric cancer cells.


Subject(s)
Adenocarcinoma , Stomach Neoplasms , Adenocarcinoma/genetics , Adenocarcinoma/pathology , Cell Line, Tumor , Cell Movement , Gene Expression Regulation, Neoplastic , Humans , Signal Transduction , Stomach Neoplasms/pathology
9.
Front Immunol ; 12: 767939, 2021.
Article in English | MEDLINE | ID: mdl-34858425

ABSTRACT

The tumor microenvironment (TME) is composed of a heterogenous population of cells that exist alongside the extracellular matrix and soluble components. These components can shape an environment that is conducive to tumor growth and metastatic spread. It is well-established that stromal cancer-associated fibroblasts (CAFs) in the TME play a pivotal role in creating and maintaining a growth-permissive environment for tumor cells. A growing body of work has uncovered that tumor cells recruit and educate CAFs to remodel the TME, however, the mechanisms by which this occurs remain incompletely understood. Recent studies suggest that the signal transducer and activator of transcription 3 (STAT3) is a key transcription factor that regulates the function of CAFs, and their crosstalk with tumor and immune cells within the TME. CAF-intrinsic STAT3 activity within the TME correlates with tumor progression, immune suppression and eventually the establishment of metastases. In this review, we will focus on the roles of STAT3 in regulating CAF function and their crosstalk with other cells constituting the TME and discuss the utility of targeting STAT3 within the TME for therapeutic benefit.


Subject(s)
Cancer-Associated Fibroblasts/immunology , Neoplasms/immunology , STAT3 Transcription Factor/immunology , Signal Transduction/immunology , Tumor Microenvironment/immunology , Cancer-Associated Fibroblasts/metabolism , Cell Communication/immunology , Disease Progression , Humans , Janus Kinases/immunology , Janus Kinases/metabolism , Neoplasms/metabolism , Neoplasms/therapy , Phosphorylation/immunology , STAT3 Transcription Factor/metabolism
10.
Int J Mol Sci ; 22(20)2021 Oct 12.
Article in English | MEDLINE | ID: mdl-34681666

ABSTRACT

Multiplex immunohistochemistry (mIHC) enables simultaneous staining of multiple immune markers on a single tissue section. Mounting studies have demonstrated the versatility of mIHC in evaluating immune infiltrates in different diseases and the tumour microenvironment (TME). However, the majority of published studies are limited to the analysis of human patient samples. Performing mIHC on formalin-fixed paraffin-embedded (FFPE) mouse tissues, particularly with sensitive antigens, remain challenging. The aim of our study was to develop a robust and reproducible protocol to uncover the immune landscape in mouse FFPE tissues. Effective antibody stripping while maintaining sensitivity to antigens and tissue adhesion to the glass slide is critical in developing an mIHC panel to allow successive rounds of staining. Thus, we identified a highly efficient stripping method that preserves signal intensity and antigenicity to allow multiple rounds of staining. We subsequently optimised an mIHC workflow with antibodies specific against CD4, CD8α, FOXP3 and B220 to identify distinct T and B cell populations on mouse FFPE tissues. Lastly, the application of this mIHC panel was validated in a mouse model of inflammatory bowel cancer, two allograft mouse models of spontaneous colon adenocarcinoma and a sporadic mouse model of colon cancer. Together, these demonstrate the utility of the aforementioned protocol in establishing the quantity and spatial localisation of immune cells in different pathological tissues.


Subject(s)
Colitis/pathology , Colonic Neoplasms/pathology , Immunohistochemistry/methods , Animals , B-Lymphocyte Subsets/cytology , B-Lymphocyte Subsets/immunology , B-Lymphocyte Subsets/metabolism , Colitis/chemically induced , Colitis/metabolism , Colonic Neoplasms/metabolism , Disease Models, Animal , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Spleen/pathology , T-Lymphocyte Subsets/cytology , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism
11.
Cancer Res ; 81(18): 4671-4672, 2021 09 15.
Article in English | MEDLINE | ID: mdl-34526349

ABSTRACT

Understanding the molecular mechanisms that underpin the pleiotropic effects of IL6 in disease are critical to better inform when this cytokine should be therapeutically targeted to provide the most benefit to patients. This is particularly important for cancer and other pathologic conditions strongly linked to chronic inflammation. Shriki and colleagues provide mechanistic evidence that IL6 protects against chronic liver injury and its ensuing tumor development, thereby challenging the prevailing paradigm that IL6 always acts as a tumor-promoting cytokine. These observations contribute to an emerging view of dichotomous and complex activities of IL6 in solid malignancies and will help understand which patients under which circumstances receive the most benefit from therapies that interfere with IL6 signaling.See related article by Shriki et al., p. 4766.


Subject(s)
Interleukin-6 , Neoplasms , Humans , Inflammation , Neoplasms/drug therapy , Signal Transduction
12.
Int J Cardiovasc Imaging ; 37(10): 3057-3068, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34338945

ABSTRACT

To evaluate the effect of percutaneous coronary intervention (PCI) of coronary chronic total occlusions (CTOs) on left ventricular (LV) strain assessed using cardiac magnetic resonance (CMR) tissue tracking. In 150 patients with a CTO, longitudinal (LS), radial (RS) and circumferential shortening (CS) were determined using CMR tissue tracking before and 3 months after successful PCI. In patients with impaired LV strain at baseline, global LS (10.9 ± 2.4% vs 11.6 ± 2.8%; P = 0.006), CS (11.3 ± 2.9% vs 12.0 ± 3.5%; P = 0.002) and RS (15.8 ± 4.9% vs 17.4 ± 6.6%; P = 0.001) improved after revascularization of the CTO, albeit to a small, clinically irrelevant, extent. Strain improvement was inversely related to the extent of scar, even after correcting for baseline strain (B = - 0.05; P = 0.008 for GLS, B = - 0.06; P = 0.016 for GCS, B = - 0.13; P = 0.017 for GRS). In the vascular territory of the CTO, dysfunctional segments showed minor improvement in both CS (10.8 [6.9 to 13.3] % vs 11.9 [8.1 to 15.0] %; P < 0.001) and RS (14.2 [8.4 to 18.7] % vs 16.0 [9.9 to 21.8] %; P < 0.001) after PCI. Percutaneous revascularization of CTOs does not lead to a clinically relevant improvement of LV function, even in the subgroup of patients and segments most likely to benefit from revascularization (i.e. LV dysfunction at baseline and no or limited myocardial scar).


Subject(s)
Coronary Occlusion , Percutaneous Coronary Intervention , Coronary Occlusion/diagnostic imaging , Coronary Occlusion/surgery , Humans , Magnetic Resonance Spectroscopy , Percutaneous Coronary Intervention/adverse effects , Predictive Value of Tests , Treatment Outcome , Ventricular Function, Left
13.
Catheter Cardiovasc Interv ; 98(5): E668-E676, 2021 11 01.
Article in English | MEDLINE | ID: mdl-34329539

ABSTRACT

OBJECTIVES: This study evaluated myocardial viability as well as global and regional functional recovery after successful chronic coronary total occlusion (CTO) percutaneous coronary intervention (PCI) using sequential quantitative cardiac magnetic resonance (CMR) imaging. BACKGROUND: The patient benefits of CTO PCI are being questioned. METHODS: In a single high-volume CTO PCI center patients were prospectively scheduled for CMR at baseline and 3 months after successful CTO PCI between 2013 and 2018. Segmental wall thickening (SWT) and percentage late gadolinium enhancement (LGE) were quantitatively measured per segment. Viability was defined as dysfunctional myocardium (<2.84 mm SWT) with no or limited scar (≤50% LGE). RESULTS: A total of 132 patients were included. Improvement of left ventricular ejection fraction was modest after CTO PCI (from 48.1 ± 11.8 to 49.5 ± 12.1%, p < 0.01). CTO segments with viability (N = 216, [31%]) demonstrated a significantly higher increase in SWT (0.80 ± 1.39 mm) compared to CTO segments with pre-procedural preserved function (N = 456 [65%], 0.07 ± 1.43 mm, p < 0.01) or extensive scar (LGE >50%, N = 26 [4%], -0.08 ± 1.09 mm, p < 0.01). Patients with ≥2 CTO segments viability showed more SWT increase in the CTO territory compared to patients with 0-1 segment viability (0.49 ± 0.93 vs. 0.12 ± 0.98 mm, p = 0.03). CONCLUSIONS: Detection of dysfunctional myocardial segments without extensive scar (≤50% LGE) as a marker for viability on CMR aids in identifying patients with significant regional functional recovery after CTO PCI.


Subject(s)
Coronary Occlusion , Percutaneous Coronary Intervention , Chronic Disease , Contrast Media , Coronary Occlusion/diagnostic imaging , Coronary Occlusion/therapy , Gadolinium , Humans , Stroke Volume , Treatment Outcome , Ventricular Function, Left
14.
Eur J Vasc Endovasc Surg ; 61(6): 1008-1016, 2021 06.
Article in English | MEDLINE | ID: mdl-33858751

ABSTRACT

OBJECTIVE: Perivascular adipose tissue (PVAT) contributes to vascular homeostasis and is increasingly linked to vascular pathology. PVAT density and volume were associated with abdominal aortic aneurysm (AAA) presence and dimensions on imaging. However, mechanisms underlying the role of PVAT in AAA have not been clarified. This study aimed to explore differences in PVAT from AAA using gene expression and functional tests. METHODS: Human aortic PVAT and control subcutaneous adipose tissue were collected during open AAA surgery. Gene analyses and functional tests were performed. The control group consisted of healthy aorta from non-living renal transplant donors. Gene expression tests were performed to study genes potentially involved in various inflammatory processes and AAA related genes. Live PVAT and subcutaneous adipose tissue (SAT) from AAA were used for ex vivo co-culture with smooth muscle cells (SMCs) retrieved from non-pathological aortas. RESULTS: Adipose tissue was harvested from 27 AAA patients (n [gene expression] = 22, n [functional tests] = 5) and five control patients. An increased inflammatory gene expression of PTPRC (p = .008), CXCL8 (p = .033), LCK (p = .003), CCL5 (p = .004) and an increase in extracellular matrix breakdown marker MMP9 (p = .016) were found in AAA compared with controls. Also, there was a decreased anti-inflammatory gene expression of PPARG in AAA compared with controls (p = .040). SMC co-cultures from non-pathological aortas with PVAT from AAA showed increased MMP9 (p = .033) and SMTN (p = .008) expression and SAT increased SMTN expression in these SMC. CONCLUSION: The data revealed that PVAT from AAA shows an increased pro-inflammatory and matrix metallopeptidase gene expression and decreased anti-inflammatory gene expression. Furthermore, increased expression of genes involved in aneurysm formation was found in healthy SMC co-culture with PVAT of AAA patients. Therefore, PVAT from AAA might contribute to inflammation of the adjacent aortic wall and thereby plays a possible role in AAA pathophysiology. These proposed pathways of inflammatory induction could reveal new therapeutic targets in AAA treatment.


Subject(s)
Aortic Aneurysm, Abdominal/genetics , Chemokine CCL5/genetics , Interleukin-8/genetics , Leukocyte Common Antigens/genetics , Lymphocyte Specific Protein Tyrosine Kinase p56(lck)/genetics , Matrix Metalloproteinase 9/genetics , Adipose Tissue/metabolism , Adipose Tissue/pathology , Aged , Aged, 80 and over , Aortic Aneurysm, Abdominal/metabolism , Aortic Aneurysm, Abdominal/pathology , Case-Control Studies , Chemokine CCL5/metabolism , Cytoskeletal Proteins/genetics , Cytoskeletal Proteins/metabolism , Female , Humans , Interleukin-8/metabolism , Leukocyte Common Antigens/metabolism , Lymphocyte Specific Protein Tyrosine Kinase p56(lck)/metabolism , Male , Matrix Metalloproteinase 9/metabolism , Middle Aged , Muscle Proteins/genetics , Muscle Proteins/metabolism , Myocytes, Smooth Muscle/metabolism , Myocytes, Smooth Muscle/pathology , PPAR gamma/genetics , PPAR gamma/metabolism , RNA, Messenger/metabolism
15.
Cancer Immunol Res ; 9(7): 735-747, 2021 07.
Article in English | MEDLINE | ID: mdl-33906864

ABSTRACT

IL11 is a member of the IL6 family of cytokines and signals through its cognate receptor subunits, IL11RA and glycoprotein 130 (GP130), to elicit biological responses via the JAK/STAT signaling pathway. IL11 contributes to cancer progression by promoting the survival and proliferation of cancer cells, but the potential immunomodulatory properties of IL11 signaling during tumor development have thus far remained unexplored. Here, we have characterized a role for IL11 in regulating CD4+ T cell-mediated antitumor responses. Absence of IL11 signaling impaired tumor growth in a sporadic mouse model of colon cancer and syngeneic allograft models of colon cancer. Adoptive bone marrow transfer experiments and in vivo depletion studies demonstrated that the tumor-promoting activity of IL11 was mediated through its suppressive effect on host CD4+ T cells in the tumor microenvironment. Indeed, when compared with Il11ra-proficient CD4+ T cells associated with MC38 tumors, their Il11ra-deficient counterparts displayed elevated expression of mRNA encoding the antitumor mediators IFNγ and TNFα. Likewise, IL11 potently suppressed the production of proinflammatory cytokines (IFNγ, TNFα, IL6, and IL12p70) by CD4+ T cells in vitro, which we corroborated by RNAscope analysis of human colorectal cancers, where IL11RAhigh tumors showed less IFNG and CD4 expression than IL11RAlow tumors. Therefore, our results ascribe a tumor cell-extrinsic immunomodulatory role to IL11 during colon cancer development that could be amenable to an anticytokine-based therapy.See related Spotlight by van der Burg, p. 724.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , Colonic Neoplasms/immunology , Interleukin-11 Receptor alpha Subunit/metabolism , Interleukin-11/metabolism , Animals , CD4 Antigens/analysis , CD4 Antigens/metabolism , CD4-Positive T-Lymphocytes/metabolism , Cell Line, Tumor , Colon/immunology , Colon/pathology , Colonic Neoplasms/pathology , Datasets as Topic , Disease Models, Animal , Gene Expression Profiling , Humans , Interferon-gamma/analysis , Interferon-gamma/metabolism , Interleukin-11 Receptor alpha Subunit/analysis , Interleukin-11 Receptor alpha Subunit/genetics , Mice , Mice, Knockout , Neoplasms, Bone Tissue , Receptors, Interleukin-11/metabolism , Tumor Microenvironment/immunology
16.
Biomedicines ; 9(2)2021 Feb 12.
Article in English | MEDLINE | ID: mdl-33673239

ABSTRACT

The intestinal epithelium provides a barrier against commensal and pathogenic microorganisms. Barrier dysfunction promotes chronic inflammation, which can drive the pathogenesis of inflammatory bowel disease (IBD) and colorectal cancer (CRC). Although the Signal Transducer and Activator of Transcription-3 (STAT3) is overexpressed in both intestinal epithelial cells and immune cells in IBD patients, the role of the interleukin (IL)-6 family of cytokines through the shared IL-6ST/gp130 receptor and its associated STAT3 signalling in intestinal barrier integrity is unclear. We therefore investigated the role of STAT3 in retaining epithelial barrier integrity using dextran sulfate sodium (DSS)-induced colitis in two genetically modified mouse models, to either reduce STAT1/3 activation in response to IL-6 family cytokines with a truncated gp130∆STAT allele (GP130∆STAT/+), or by inducing short hairpin-mediated knockdown of Stat3 (shStat3). Here, we show that mice with reduced STAT3 activity are highly susceptible to DSS-induced colitis. Mechanistically, the IL-6/gp130/STAT3 signalling cascade orchestrates intestinal barrier function by modulating cytokine secretion and promoting epithelial integrity to maintain a defence against bacteria. Our study also identifies a crucial role of STAT3 in controlling intestinal permeability through tight junction proteins. Thus, therapeutically targeting the IL-6/gp130/STAT3 signalling axis to promote barrier function may serve as a treatment strategy for IBD patients.

17.
EuroIntervention ; 16(6): e453-e461, 2020 08 07.
Article in English | MEDLINE | ID: mdl-32122823

ABSTRACT

AIMS: This study aimed to evaluate associations between coronary collaterals and myocardial viability as assessed by quantitative cardiac magnetic resonance (CMR) imaging in patients with a chronic coronary total occlusion (CTO). METHODS AND RESULTS: A total of 218 patients with a CTO who underwent CMR between 2013 and 2018 were included. A concomitant collateral connection (CC) score 2 and Rentrop grade 3 defined well-developed collaterals in 146 (67%) patients, whereas lower CC scores or Rentrop grades characterised poorly developed collaterals. Dysfunctional myocardium (<3 mm segmental wall thickening [SWT]) and ≤50% late gadolinium enhancement (LGE) defined viability. Extensive scar (LGE >50%) was observed in only 5% of CTO segments. In the CTO territory, SWT was greater (3.72±1.51 vs 3.05±1.60 mm, p<0.01) and the extent of scar was less (7.0 [0.1-16.7] vs 13.1% [2.8-22.2], p=0.048) in patients having well-developed versus poorly developed collaterals. Viability was more prevalent in CTO segments among patients with poorly developed versus well-developed collaterals (44% vs 30% of segments, p<0.01), predominantly due to a higher prevalence of dysfunctional myocardium (51% vs 34% of segments, p<0.01) in the poorly developed collateral group. CONCLUSIONS: The infarcted area in myocardium subtended by a CTO is generally limited. Well-developed collaterals are associated with less myocardial scar and enhanced preserved function. However, viability was regularly present in patients with poorly developed collaterals.


Subject(s)
Collateral Circulation , Coronary Angiography , Coronary Occlusion , Heart/diagnostic imaging , Chronic Disease , Contrast Media/administration & dosage , Gadolinium/administration & dosage , Humans , Myocardium
18.
Can J Diabetes ; 44(2): 184-191, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31451424

ABSTRACT

OBJECTIVE: Diet-related quality of life has not been explored previously in patients with type 2 diabetes using sodium glucose cotransporter 2 (SGLT-2) inhibitors, the latest class of diabetes medications. In this study, we sought to describe the patient experience on SGLT-2 inhibitors and examine whether there have been improvements in dietary perception and satisfaction with these drugs. METHODS: Adults ≥40 years of age with type 2 diabetes and using SGLT-2 inhibitors for at least 1 month were recruited to take part in one-time 1-on-1 interviews. An interpretive descriptive methodology was used. Data collection and analysis occurred concurrently and a constant comparative analysis was used. RESULTS: An overall positive response to SGLT-2 inhibitor use was observed. Interviews revealed 3 themes: Recognizing, Reckoning and Realizing. In Recognizing, all patients reported a significant relationship with food that was typically negative and included feelings of food restriction and deprivation. Positive side effects of the drug in Reckoning included better glycemic control, weight loss and improved energy. Some participants were motivated in Realizing to pursue additional behavioural changes to improve their diabetes management. CONCLUSIONS: An improved dietary-related quality of life was described by some participants. Although not all individuals were seen to move into the Realizing phase after initiating an SGLT-2 inhibitor, there appeared to be an opportunity to create a behaviour change after positive Reckoning experiences.


Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Patient Satisfaction , Sodium-Glucose Transporter 2 Inhibitors/therapeutic use , Aged , Female , Humans , Male , Middle Aged , Quality of Life
19.
EMBO Mol Med ; 11(4)2019 04.
Article in English | MEDLINE | ID: mdl-30885958

ABSTRACT

Excessive signaling through gp130, the shared receptor for the interleukin (IL)6 family of cytokines, is a common hallmark in solid malignancies and promotes their progression. Here, we established the in vivo utility of bazedoxifene, a steroid analog clinically approved for the treatment of osteoporosis, to suppress gp130-dependent tumor growth of the gastrointestinal epithelium. Bazedoxifene administration reduced gastric tumor burden in gp130Y757F mice, where tumors arise exclusively through excessive gp130/STAT3 signaling in response to the IL6 family cytokine IL11. Likewise, in mouse models of sporadic colon and intestinal cancers, which arise from oncogenic mutations in the tumor suppressor gene Apc and the associated ß-catenin/canonical WNT pathway, bazedoxifene treatment reduces tumor burden. Consistent with the proposed orthogonal tumor-promoting activity of IL11-dependent gp130/STAT3 signaling, tumors of bazedoxifene-treated Apc-mutant mice retain excessive nuclear accumulation of ß-catenin and aberrant WNT pathway activation. Likewise, bazedoxifene treatment of human colon cancer cells harboring mutant APC did not reduce aberrant canonical WNT signaling, but suppressed IL11-dependent STAT3 signaling. Our findings provide compelling proof of concept to support the repurposing of bazedoxifene for the treatment of gastrointestinal cancers in which IL11 plays a tumor-promoting role.


Subject(s)
Drug Repositioning , Gastrointestinal Neoplasms/drug therapy , Indoles/therapeutic use , Selective Estrogen Receptor Modulators/therapeutic use , Adenomatous Polyposis Coli Protein/genetics , Animals , Cell Proliferation/drug effects , Cytokine Receptor gp130/chemistry , Cytokine Receptor gp130/metabolism , Disease Models, Animal , Female , Gastrointestinal Neoplasms/pathology , Humans , Indoles/metabolism , Indoles/pharmacology , Interleukin-11/chemistry , Interleukin-11/metabolism , Interleukin-11/pharmacology , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , STAT3 Transcription Factor/metabolism , Selective Estrogen Receptor Modulators/metabolism , Selective Estrogen Receptor Modulators/pharmacology , Signal Transduction/drug effects , Xenograft Model Antitumor Assays , beta Catenin/metabolism
20.
Nat Rev Cancer ; 19(2): 82-96, 2019 02.
Article in English | MEDLINE | ID: mdl-30578415

ABSTRACT

The tightly orchestrated temporal and spatial control of signal transducer and activator of transcription 3 (STAT3) activity in epithelial, immune and stromal cells is critical for wound healing and tissue repair. Excessive STAT3 activation within cancer cells and cells of the tumour microenvironment can be viewed as a neoplastic mimic of an inflammation-driven repair response that collectively promotes tumour progression. In addition to the canonical transcriptional pathways by which STAT3 promotes stem cell-like characteristics, survival, proliferation, metastatic potential and immune evasion, cytoplasmic STAT3 activity fuels tumour growth by metabolic and other non-transcriptional mechanisms. Here, we review the tumour-modulating activities of STAT3 in light of its role as a signalling node integrating inflammatory responses during wound healing. Accordingly, many of the cytokines that contribute to the para-inflammatory state of most solid malignancies converge on and underpin dysregulated STAT3 activity. Targeting of these cytokines, their cognate receptors and associated signalling cascades in clinical trials is beginning to demonstrate therapeutic efficacy, given that interference with STAT3 activity is likely to simultaneously curb the growth of cancer cells and augment antitumour immunity.


Subject(s)
Neoplasms/metabolism , Neoplasms/pathology , STAT3 Transcription Factor/metabolism , Animals , Cell Transformation, Neoplastic/metabolism , Cell Transformation, Neoplastic/pathology , Cytokines/metabolism , Humans , Inflammation/metabolism , Inflammation/pathology , Signal Transduction/physiology , Tumor Microenvironment/physiology
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