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Neutrophils are dynamic cells, playing a critical role in pathogen clearance; however, neutrophil infiltration into the tissue can act as a double-edged sword. They are one of the primary sources of excessive inflammation during infection, which has been observed in many infectious diseases including pneumonia and active tuberculosis (TB). Neutrophil function is influenced by interactions with other immune cells within the inflammatory lung milieu; however, how these interactions affect neutrophil function is unclear. Our study examined the macrophage–neutrophil axis by assessing the effects of conditioned medium (MΦ-CM) from primary human monocyte-derived macrophages (hMDMs) stimulated with LPS or a whole bacterium (Mycobacterium tuberculosis) on neutrophil function. Stimulated hMDM-derived MΦ-CM boosts neutrophil activation, heightening oxidative and glycolytic metabolism, but diminishes migratory potential. These neutrophils exhibit increased ROS production, elevated NET formation, and heightened CXCL8, IL-13, and IL-6 compared to untreated or unstimulated hMDM-treated neutrophils. Collectively, these data show that MΦ-CM from stimulated hMDMs activates neutrophils, bolsters their energetic profile, increase effector and inflammatory functions, and sequester them at sites of infection by decreasing their migratory capacity. These data may aid in the design of novel immunotherapies for severe pneumonia, active tuberculosis and other diseases driven by pathological inflammation mediated by the macrophage–neutrophil axis. [ABSTRACT FROM AUTHOR]

Obesity is a major driving factor in the incidence, progression, and poor treatment response in gastrointestinal cancers. Herein, we conducted a comprehensive analysis of the impact of obesity and its resulting metabolic perturbations across four gastrointestinal cancer types, namely, oesophageal, gastric, liver, and colorectal cancer. Importantly, not all obese phenotypes are equal. Obese adipose tissue heterogeneity depends on the location, structure, cellular profile (including resident immune cell populations), and dietary fatty acid intake. We discuss whether adipose heterogeneity impacts the tumorigenic environment. Dietary fat quality, in particular saturated fatty acids, promotes a hypertrophic, pro-inflammatory adipose profile, in contrast to monounsaturated fatty acids, resulting in a hyperplastic, less inflammatory adipose phenotype. The purpose of this review is to examine the impact of obesity, including dietary fat quality, on adipose tissue biology and oncogenesis, specifically focusing on lipid metabolism and inflammatory mechanisms. This is achieved with a particular focus on gastrointestinal cancers as exemplar models of obesity-associated cancers. [ABSTRACT FROM AUTHOR]

Resistance to neoadjuvant chemoradiation therapy is a significant clinical challenge in the management of rectal cancer. There is an unmet need to identify the underlying mechanisms of treatment resistance to enable the development of biomarkers predictive of response and novel treatment strategies to improve therapeutic response. In this study, an in vitro model of inherently radioresistant rectal cancer was identified and characterized to identify mechanisms underlying radioresistance in rectal cancer. Transcriptomic and functional analysis demonstrated significant alterations in multiple molecular pathways, including the cell cycle, DNA repair efficiency and upregulation of oxidative phosphorylation-related genes in radioresistant SW837 rectal cancer cells. Real-time metabolic profiling demonstrated decreased reliance on glycolysis and enhanced mitochondrial spare respiratory capacity in radioresistant SW837 cells when compared to radiosensitive HCT116 cells. Metabolomic profiling of pre-treatment serum samples from rectal cancer patients (n = 52) identified 16 metabolites significantly associated with subsequent pathological response to neoadjuvant chemoradiation therapy. Thirteen of these metabolites were also significantly associated with overall survival. This study demonstrates, for the first time, a role for metabolic reprograming in the radioresistance of rectal cancer in vitro and highlights a potential role for altered metabolites as novel circulating predictive markers of treatment response in rectal cancer patients. [ABSTRACT FROM AUTHOR]

Simple Summary: Oesophageal adenocarcinoma (OAC) is a poor prognosis cancer with limited response rates to current treatment modalities and is strongly linked to obesity status and metabolic dysfunction. This study for the first time has conducted a detailed assessment of adipose tissue metabolism, as well as assessing adipose secreted pro-inflammatory, metabolite, and lipid profiles to determine whether these profiles correlate with significant clinical parameters in OAC patients including obesity, metabolic dysfunction, previous treatment exposure, and tumour regression grades. Overall, in this study, increases in metabolic profiles linked with oxidative phosphorylation, pro-inflammatory cytokines, and metabolites associated with aiding tumorigenesis have been identified in the most viscerally obese OAC patients and in patients with metabolic dysfunction. These results raise the question of whether targeting these altered signalling mechanisms could aid current treatment strategies. Oesophageal adenocarcinoma (OAC) is a poor prognosis cancer with limited response rates to current treatment modalities and has a strong link to obesity. To better elucidate the role of visceral adiposity in this disease state, a full metabolic profile combined with analysis of secreted pro-inflammatory cytokines, metabolites, and lipid profiles were assessed in human ex vivo adipose tissue explants from obese and non-obese OAC patients. These data were then related to extensive clinical data including obesity status, metabolic dysfunction, previous treatment exposure, and tumour regression grades. Real-time energy metabolism profiles were assessed using the seahorse technology. Adipose explant conditioned media was screened using multiplex ELISA to assess secreted levels of 54 pro-inflammatory mediators. Targeted secreted metabolite and lipid profiles were analysed using Ultra-High-Performance Liquid Chromatography coupled with Mass Spectrometry. Adipose tissue explants and matched clinical data were collected from OAC patients (n = 32). Compared to visceral fat from non-obese patients (n = 16), visceral fat explants from obese OAC patients (n = 16) had significantly elevated oxidative phosphorylation metabolism profiles and an increase in Eotaxin-3, IL-17A, IL-17D, IL-3, MCP-1, and MDC and altered secretions of glutamine associated metabolites. Adipose explants from patients with metabolic dysfunction correlated with increased oxidative phosphorylation metabolism, and increases in IL-5, IL-7, SAA, VEGF-C, triacylglycerides, and metabolites compared with metabolically healthy patients. Adipose explants generated from patients who had previously received neo-adjuvant chemotherapy (n = 14) showed elevated secretions of pro-inflammatory mediators, IL-12p40, IL-1α, IL-22, and TNF-β and a decreased expression of triacylglycerides. Furthermore, decreased secreted levels of triacylglycerides were also observed in the adipose secretome of patients who received the chemotherapy-only regimen FLOT compared with patients who received no neo-adjuvant treatment or chemo-radiotherapy regimen CROSS. For those patients who showed the poorest response to currently available treatments, their adipose tissue was associated with higher glycolytic metabolism compared to patients who had good treatment responses. This study demonstrates that the adipose secretome in OAC patients is enriched with mediators that could prime the tumour microenvironment to aid tumour progression and attenuate responses to conventional cancer treatments, an effect which appears to be augmented by obesity and metabolic dysfunction and exposure to different treatment regimes. [ABSTRACT FROM AUTHOR]

Neoadjuvant chemoradiation therapy (CRT) is increasingly the standard of care for locally advanced oesophageal cancer. A complete pathological response to CRT is associated with a favourable outcome. Radiation therapy is important for local tumour control, however, radioresistance remains a substantial clinical problem. We hypothesise that alterations in mitochondrial function and energy metabolism are involved in the radioresistance of oesophageal adenocarcinoma (OAC). To investigate this, we used an established isogenic cell line model of radioresistant OAC. Radioresistant cells (OE33 R) demonstrated significantly increased levels of random mitochondrial mutations, which were coupled with alterations in mitochondrial function, size, morphology and gene expression, supporting a role for mitochondrial dysfunction in the radioresistance of this model. OE33 R cells also demonstrated altered bioenergetics, demonstrating significantly increased intracellular ATP levels, which was attributed to enhanced mitochondrial respiration. Radioresistant cells also demonstrated metabolic plasticity, efficiently switching between the glycolysis and oxidative phosphorylation energy metabolism pathways, which were accompanied by enhanced clonogenic survival. This data was supported in vivo, in pre-treatment OAC tumour tissue. Tumour ATP5B expression, a marker of oxidative phosphorylation, was significantly increased in patients who subsequently had a poor pathological response to neoadjuvant CRT. This suggests for the first time, a role for specific mitochondrial alterations and metabolic remodelling in the radioresistance of OAC. [ABSTRACT FROM AUTHOR]

Reprogramming of cellular metabolism is an emerging hallmark of neoplastic transformation. However, it is not known how the expression of metabolic genes in tumors differs from that in normal tissues, or whether different tumor types exhibit similar metabolic changes. Here we compare expression patterns of metabolic genes across 22 diverse types of human tumors. Overall, the metabolic gene expression program in tumors is similar to that in the corresponding normal tissues. Although expression changes of some metabolic pathways (e.g., upregulation of nucleotide biosynthesis and glycolysis) are frequently observed across tumors, expression changes of other pathways (e.g., oxidative phosphorylation) are very heterogeneous. Our analysis also suggests that the expression changes of some metabolic genes (e.g., isocitrate dehydrogenase and fumarate hydratase) may enhance or mimic the effects of recurrent mutations in tumors. On the level of individual biochemical reactions, many hundreds of metabolic isoenzymes show significant and tumor-specific expression changes. These isoenzymes are potential targets for anticancer therapy. [ABSTRACT FROM AUTHOR]

Oesophageal adenocarcinoma (OAC) is an exemplar model of obesity-associated cancer. Previous work in our group has demonstrated that overweight/obese OAC patients have better responses to neoadjuvant therapy, but the underlying mechanisms are unknown. Unravelling the immune–metabolic signatures of adipose tissue may provide insight for this observation. We hypothesised that different metabolic pathways predominate in visceral (VAT) and subcutaneous adipose tissue (SAT) and inflammatory secretions will differ between the fat depots. Real-time ex vivo metabolic profiles of VAT and SAT from 12 OAC patients were analysed. These samples were screened for the secretion of 54 inflammatory mediators, and data were correlated with patient body composition. Oxidative phosphorylation (OXPHOS) was significantly higher in VAT when compared to SAT. OXPHOS was significantly higher in the SAT of patients receiving neoadjuvant treatment. VEGF-A, VEGF-C, P1GF, Flt-1, bFGF, IL-15, IL-16, IL-17A, CRP, SAA, ICAM-1, VCAM-1, IL-2, IL-13, IFN-γ, and MIP-1β secretions were significantly higher from VAT than SAT. Higher levels of bFGF, Eotaxin-3, and TNF-α were secreted from the VAT of obese patients, while higher levels of IL-23 and TARC were secreted from the SAT of obese patients. The angiogenic factors, bFGF and VEGF-C, correlated with visceral fat area. Levels of OXPHOS are higher in VAT than SAT. Angiogenic, vascular injury and inflammatory cytokines are elevated in VAT versus SAT, indicating that VAT may promote inflammation, linked to regulating treatment response. [ABSTRACT FROM AUTHOR]

Simple Summary: This research investigates the disease relevance and therapeutic potential of cysteinyl leukotriene receptors in uveal melanoma (UM), a rare eye cancer that often spreads to the liver. Unfortunately, there are no therapies available to stop the spread of UM and patients are often faced with an extremely poor prognosis. We assess whether the cysteinyl leukotriene receptors (CysLT1 and CysLT2) are relevant to the progression of UM. Using UM patient samples, we identified that increased levels of CysLT1 in tumours is associated with reduced patient survival. Using UM cell lines and zebrafish models, we found that drugs targeting CysLT1, but not CysLT2, can alter hallmarks of cancer including cell growth, proliferation, and metabolism. This study is the first to examine the relationship of the CysLT receptors with clinical features of UM. Our data strengthen the importance of CysLT signalling in UM and suggest that antagonism of CysLT1 may be of therapeutic interest in the disease. Metastatic uveal melanoma (UM) is a rare, but often lethal, form of ocular cancer arising from melanocytes within the uveal tract. UM has a high propensity to spread hematogenously to the liver, with up to 50% of patients developing liver metastases. Unfortunately, once liver metastasis occurs, patient prognosis is extremely poor with as few as 8% of patients surviving beyond two years. There are no standard-of-care therapies available for the treatment of metastatic UM, hence it is a clinical area of urgent unmet need. Here, the clinical relevance and therapeutic potential of cysteinyl leukotriene receptors (CysLT1 and CysLT2) in UM was evaluated. High expression of CYSLTR1 or CYSLTR2 transcripts is significantly associated with poor disease-free survival and poor overall survival in UM patients. Digital pathology analysis identified that high expression of CysLT1 in primary UM is associated with reduced disease-specific survival (p = 0.012; HR 2.76; 95% CI 1.21–6.3) and overall survival (p = 0.011; HR 1.46; 95% CI 0.67–3.17). High CysLT1 expression shows a statistically significant (p = 0.041) correlation with ciliary body involvement, a poor prognostic indicator in UM. Small molecule drugs targeting CysLT1 were vastly superior at exerting anti-cancer phenotypes in UM cell lines and zebrafish xenografts than drugs targeting CysLT2. Quininib, a selective CysLT1 antagonist, significantly inhibits survival (p < 0.0001), long-term proliferation (p < 0.0001), and oxidative phosphorylation (p < 0.001), but not glycolysis, in primary and metastatic UM cell lines. Quininib exerts opposing effects on the secretion of inflammatory markers in primary versus metastatic UM cell lines. Quininib significantly downregulated IL-2 and IL-6 in Mel285 cells (p < 0.05) but significantly upregulated IL-10, IL-1β, IL-2 (p < 0.0001), IL-13, IL-8 (p < 0.001), IL-12p70 and IL-6 (p < 0.05) in OMM2.5 cells. Finally, quininib significantly inhibits tumour growth in orthotopic zebrafish xenograft models of UM. These preclinical data suggest that antagonism of CysLT1, but not CysLT2, may be of therapeutic interest in the treatment of UM. [ABSTRACT FROM AUTHOR]

Cisplatin (cis-diamminedichloroplatinum) is widely used for the treatment of solid malignancies; however, the development of chemoresistance hinders the success of this chemotherapeutic in the clinic. This study provides novel insights into the molecular and phenotypic changes in an isogenic oesophageal adenocarcinoma (OAC) model of acquired cisplatin resistance. Key differences that could be targeted to overcome cisplatin resistance are highlighted. We characterise the differences in treatment sensitivity, gene expression, inflammatory protein secretions, and metabolic rate in an isogenic cell culture model of acquired cisplatin resistance in OAC. Cisplatin-resistant cells (OE33 Cis R) were significantly more sensitive to other cytotoxic modalities, such as 2 Gy radiation (p = 0.0055) and 5-fluorouracil (5-FU) (p = 0.0032) treatment than parental cisplatin-sensitive cells (OE33 Cis P). Gene expression profiling identified differences at the gene level between cisplatin-sensitive and cisplatin-resistant cells, uncovering 692 genes that were significantly altered between OE33 Cis R cells and OE33 Cis P cells. OAC is an inflammatory-driven cancer, and inflammatory secretome profiling identified 18 proteins secreted at significantly altered levels in OE33 Cis R cells compared to OE33 Cis P cells. IL-7 was the only cytokine to be secreted at a significantly higher levels from OE33 Cis R cells compared to OE33 Cis P cells. Additionally, we profiled the metabolic phenotype of OE33 Cis P and OE33 Cis R cells under normoxic and hypoxic conditions. The oxygen consumption rate, as a measure of oxidative phosphorylation, is significantly higher in OE33 Cis R cells under normoxic conditions. In contrast, under hypoxic conditions of 0.5% O2, the oxygen consumption rate is significantly lower in OE33 Cis R cells than OE33 Cis P cells. This study provides novel insights into the molecular and phenotypic changes in an isogenic OAC model of acquired cisplatin resistance, and highlights therapeutic targets to overcome cisplatin resistance in OAC. [ABSTRACT FROM AUTHOR]

Background Oesophageal Cancer (OAC) is an aggressive disease with survival rates of ∼15-20%. Current therapeutic regimes focus on neo-adjuvant therapy (chemo-radiation) prior to surgery. Unfortunately, only 20–30% of patients show a beneficial response, with 70–80% of patients as non-responders. This major clinical challenge of treatment resistance reinforces the need for the identification of novel treatments which can act as radio-sensitisers in the neo-adjuvant setting. Methods Through a drug screening approach in-vivo, we have identified a novel anti-angiogenic and anti-metabolic compound, 11B_CC8 with radiosensitising activity. The ability of 11B_CC8 to act as an anti-metabolic agent under hypoxia was evaluated using the XFe24 Seahorse analyser and the Don Whitley i2 workstation. The ability of 11B_CC8 to radiosensitise our isogenic OAC cells under hypoxic conditions was assessed by clonogenic assay. The effect of 11B_CC8 on inflammatory, metabolic and angiogenic protein secretions from OAC treatment naïve tumour conditioned media (TCM) was evaluated by multiplex ELISA. Fresh treatment naïve patient biopsies were screened for their metabolic activity using the XFe24 seahorse analyser at baseline and post- treatment with 11B_CC8. The elucidation of the possible mechanism of action of 11B_CC8 was evaluated by Mass-Spectrometry. Results Our novel anti-angiogenic and anti-metabolic agent can enhance radiosensitivity in our isogenic model of OAC under both normoxic and hypoxic (0.5% O 2) conditions. 11B_CC8 significantly reduces oxygen consumption rate (OCR) under normoxic but not hypoxic conditions. Ex-vivo, 11B_CC8 significantly reduced the secretion of IL1β (P  = 0.0117). Real-time ex-vivo metabolic rate analysis of our treatment naïve OAC biopsies showed significantly elevated OCR, when compared to Extracellular Acidification rate, a measure of glycolysis (P  = 0.0059). Treatment with 11B_CC8 produced a reduction in OCR (P  = 0.0039). Conclusion Our novel anti-angiogenic and anti-metabolic agent can enhance radiosensitivity in-vitro under both normoxic and hypoxic conditions. Ex-vivo, treatment naïve OAC human patient samples, 11B_CC8 can significantly reduce the secretion of IL1β and altered metabolic programming, specifically oxidative phosphorylation in human explants. Disclosure All authors have declared no conflicts of interest. [ABSTRACT FROM AUTHOR]

Oesophageal adenocarcinoma (OAC) is an aggressive disease with 5-year survival rates of <20%. Only 20-30% OAC patients show a beneficial response to neoadjuvant therapy. Altered mitochondrial function is linked with radioresistance in OAC. We identified pyrazinib (P3), a pyrazine phenol small molecule drug with anti-angiogenic and anti-metabolic activity in-vivo in zebrafish and in-vitro isogenic models of OAC radioresistance. Pyrazinib (P3) significantly inhibited blood vessel development in zebrafish (p < 0.001). In-vivo in zebrafish and in-vitro in an isogenic model of OAC radioresistance, pyrazinib (P3) significantly reduced measures of oxidative phosphorylation and glycolysis. Pyrazinib (P3) significantly reduced the surviving fraction in OE33P; radiation-sensitive and OE33R; radiation-resistant cells following irradiation. Under hypoxic conditions pyrazinib (P3) significantly reduced OE33R cell survival following 4 Gy irradiation (p = 0.0216). Multiplex ELISA showed significantly higher secreted levels of 9 of 30 detected inflammatory and angiogenic factors in OE33R radioresistant cells compared to OE33P cells; IL-8, IL-4, IL-6, IL-2, IL-12p70, IL-10, MCP-1, IP-10, ICAM (p < 0.05). Pyrazinib (P3) significantly reduced the secretions of IL-6 (p = 0.0006), IL-8 (p = 0.0488), and IL-4 (p = 0.0111) in OE33R cells. Collectively, these findings support further development of pyrazinib (P3) as a novel therapeutic radiosensitiser in OAC. [ABSTRACT FROM AUTHOR]