Independent transcriptional patterns reveal biological processes associated with disease-free survival in early colorectal cancer.

BACKGROUND: Bulk transcriptional profiles of early colorectal cancer (CRC) can fail to detect biological processes associated with disease-free survival (DFS) if the transcriptional patterns are subtle and/or obscured by other processes' patterns. Consensus-independent component analysis (c-ICA) can dissect such transcriptomes into statistically independent transcriptional components (TCs), capturing both pronounced and subtle biological processes. METHODS: In this study we (1) integrated transcriptomes (n = 4228) from multiple early CRC studies, (2) performed c-ICA to define the TC landscape within this integrated data set, 3) determined the biological processes captured by these TCs, (4) performed Cox regression to identify DFS-associated TCs, (5) performed random survival forest (RSF) analyses with activity of DFS-associated TCs as classifiers to identify subgroups of patients, and 6) performed a sensitivity analysis to determine the robustness of our results RESULTS: We identify 191 TCs, 43 of which are associated with DFS, revealing transcriptional diversity among DFS-associated biological processes. A prominent example is the epithelial-mesenchymal transition (EMT), for which we identify an association with nine independent DFS-associated TCs, each with coordinated upregulation or downregulation of various sets of genes. CONCLUSIONS: This finding indicates that early CRC may have nine distinct routes to achieve EMT, each requiring a specific peri-operative treatment strategy. Finally, we stratify patients into DFS patient subgroups with distinct transcriptional patterns associated with stage 2 and stage 3 CRC.

While treatments for patients with colorectal cancer have improved, many patients (around 30-50%) have cancers that will eventually relapse and these patients will die due to their disease. Researchers have been studying the genes involved in colorectal cancer to help us understand why some cancers might relapse. However, current methods to do this may miss subtle or hidden patterns in the gene activity related to cancer relapse. To deal with this, we used a special method called consensus-independent component analysis (c-ICA) to dig more deeply into the activity of genes. This helped us to uncover some potential biological processes underpinning colorectal cancer relapse, which ultimately could help researchers to identify better treatments for patients with colorectal cancer.

Continuous administration of enteral lipid- and protein-rich nutrition limits inflammation in a human endotoxemia model.

OBJECTIVE: An overzealous inflammatory response is an important cause of morbidity and mortality in surgical, trauma, and critically ill patients. Enteral administration of lipid-rich nutrition was previously shown to attenuate inflammation and reduce organ damage via a cholecystokinin-1 receptor-mediated vagovagal reflex in animal studies. The current preclinical study investigates the immunomodulatory potential of a custom-made enteral nutrition during systemic inflammation in man. DESIGN: Double-blind, randomized controlled trial. SETTING: Intensive care research unit. SUBJECTS: Male volunteers. INTERVENTIONS: After an overnight fast, 18 healthy male subjects received an IV bolus of Escherichia coli lipopolysaccharide (2 ng/kg). Subjects in the fasted group (n = 6) were deprived of food throughout the study, while subjects in the intervention groups were fed either custom-made lipid- and protein-rich nutrition (n = 6) or isocaloric control nutrition (n = 6) via nasojejunal tube, starting 1 hour prior to lipopolysaccharide administration until 6 hours afterward. MEASUREMENTS AND MAIN RESULTS: Bolus lipopolysaccharide administration resulted in a marked inflammatory response. Continuous postpyloric administration of nutrition significantly increased plasma cholecystokinin levels throughout the lipopolysaccharide-induced inflammatory response. Lipid- and protein-rich nutrition attenuated circulating levels of the proinflammatory cytokines tumor necrosis factor-α and interleukin-6 and the interleukin-1 receptor antagonist compared with control nutrition (all p < 0.05) and fasted subjects (all p < 0.05). In additional, lipid- and protein-rich nutrition augmented the anti-inflammatory response, reflected by increased plasma levels of interleukin-10 compared with fasted subjects (p < 0.0001). CONCLUSIONS: The current preclinical study expands the immunomodulating effects of enteral nutrition as previously observed in rodents to man. Continuous administration of enteral nutrition resulted in a rapid anti-inflammatory effect. Furthermore, enrichment of the nutritional composition with lipid and protein was shown to enhance the anti-inflammatory potential. Therefore, continuous enteral administration of lipid- and protein-rich nutrition is a promising intervention to modulate the immune response in the early course of systemic inflammation in man.

Level of activation of the unfolded protein response correlates with Paneth cell apoptosis in human small intestine exposed to ischemia/reperfusion.

BACKGROUND & AIMS: In the intestine, Paneth cells participate in the innate immune response. Their highly secretory function makes them susceptible to environmental conditions that cause endoplasmic reticulum (ER) stress. We investigated whether intestinal ischemia/reperfusion (I/R) induces ER stress, thereby activating the unfolded protein response (UPR), and whether excessive UPR activation affects Paneth cells. In addition, we investigated the consequences of Paneth cell compromise during physical barrier damage. METHODS: Jejunal I/R was studied using a human experimental model (n = 30 patients). Activation of the UPR was assessed using immunofluorescence for binding protein and quantitative polymerase chain reaction analyses for C/EBP homologous protein (CHOP), growth arrest and DNA-damage inducible protein 34 (GADD34), and X-box binding protein 1 (XBP1) splicing. Paneth cell apoptosis was assessed by double staining for lysozyme and M30. Male Sprague-Dawley rats underwent either intestinal I/R to investigate UPR activation and Paneth cell apoptosis, or hemorrhagic shock with or without intraperitoneal administration of dithizone, to study consequences of Paneth cell compromise during physical intestinal damage. In these animals, bacterial translocation and circulating tumor necrosis factor-α and interleukin-6 levels were assessed. RESULTS: In jejunum samples from humans and rats, I/R activated the UPR and resulted in Paneth cell apoptosis. Apoptotic Paneth cells showed signs of ER stress, and Paneth cell apoptosis correlated with the extent of ER stress. Apoptotic Paneth cells were shed into the crypt lumen, significantly lowering their numbers. In rats, Paneth cell compromise increased bacterial translocation and inflammation during physical intestinal damage. CONCLUSIONS: ER stress-induced Paneth cell apoptosis contributes to intestinal I/R-induced bacterial translocation and systemic inflammation.

Lipid-enriched enteral nutrition controls the inflammatory response in murine Gram-negative sepsis.

OBJECTIVES: Controlling the inflammatory cascade during sepsis remains a major clinical challenge. Recently, it has become evident that the autonomic nervous system reduces inflammation through the vagus nerve. The current study investigates whether nutritional stimulation of the autonomic nervous system effectively attenuates the inflammatory response in murine Gram-negative sepsis. DESIGN: Controlled in vivo and ex vivo experimental study. SETTINGS: Research laboratory of a university hospital. SUBJECTS: Male C57bl6 mice. INTERVENTIONS: Mice were intraperitoneally challenged with lipopolysaccharide derived from Escherichia coli. Before lipopolysaccharide administration, mice were fasted or enterally fed either lipid-rich nutrition or low-lipid nutrition. Antagonists to cholecystokinin receptors or nicotinic receptors were administered before lipopolysaccharide administration. Blood and tissue samples were collected at 90 mins. Mesenteric afferent discharge was determined in ex vivo preparations in response to both nutritional compositions. MEASUREMENTS AND MAIN RESULTS: Both lipid-rich and low-lipid nutrition dose-dependently reduced lipopolysaccharide-induced tumor necrosis factor-α release (high dose: both 1.4 ± 0.4 ng/mL) compared with fasted mice (3.7 ± 0.8 ng/mL; p < .01). The anti-inflammatory effect of both nutritional compositions was mediated through cholecystokinin receptors (p < .01), activation of mesenteric vagal afferents (p < .05), and peripheral nicotinic receptors (p < .05). Lipid-rich nutrition attenuated the inflammatory response at lower dosages than low-lipid nutrition, indicating that enrichment of enteral nutrition with lipid augments the anti-inflammatory potential. Administration of lipid-rich nutrition prevented endotoxin-induced small intestinal epithelium damage and reduced inflammation in the liver and spleen compared with fasted (all p < .01) and low-lipid nutrition controls (all p < .05). CONCLUSIONS: The current study demonstrates that lipid-rich nutrition attenuates intestinal damage and systemic as well as organ-specific inflammation in murine Gram-negative sepsis through the nutritional vagal anti-inflammatory pathway. These findings implicate enteral administration of lipid-enriched nutrition as a promising intervention to modulate the inflammatory response during septic conditions.

Urine-based detection of intestinal tight junction loss.

BACKGROUND: Tight junction breakdown, with loss of the important sealing protein claudin-3, is an early event in the development of intestinal damage. Therefore, noninvasive analysis of intestinal tight junction status could be helpful in early detection of intestinal injury. AIM: To investigate the usefulness of urinary claudin-3 as marker for intestinal tight junction loss. METHODS: A rat hemorrhagic shock model and a human setting of known intestinal damage, that is, patients with relapsed inflammatory bowel disease (IBD), were used to investigate intestinal tight junction status by immunohistochemical staining and urinary claudin-3 levels by western blot. RESULTS: In rats claudin-3 urine levels increased rapidly after histologically proven intestinal tight junction loss, with significantly elevated levels at 90 minutes after shock compared with sham-operated animals [mean+/-SEM: 611+/-101 intensity (INT), n=6 vs. 232+/-30 INT, n=6; P<0.05]. Moreover, in colonic biopsies of patients with IBD relapse claudin-3 staining was reduced compared with biopsies of patients with IBD without signs of disease. Concomitantly, significantly increased claudin-3 urine levels were found in these patients (502+/-67 INT, n=10) compared with patients with IBD in remission (219+/-17 INT, n=10, P<0.001) and healthy volunteers (225+/-38 INT, n=10, P<0.001). CONCLUSION: Here we show for the first time in both an experimental and clinical setting a strong relation between intestinal tight junction loss and urinary claudin-3 levels. These findings suggest that measurement of urinary claudin-3 can be used as noninvasive marker for intestinal tight junction loss. This offers new opportunities for early diagnosis and follow-up of intestinal injury.

Lipid-rich enteral nutrition reduces postoperative ileus in rats via activation of cholecystokinin-receptors.

OBJECTIVE: This study investigates the effect of lipid-rich nutrition on the local inflammatory response and gastrointestinal hypomotility in a rat model of postoperative ileus. BACKGROUND: Postoperative ileus is a major clinical problem, in which inflammation of the intestinal muscularis plays a key pathogenic event. Previously, administration of lipid-rich nutrition has been shown to reduce inflammation by activation of the autonomic nervous system via cholecystokinin-receptors. METHODS: Postoperative ileus was induced by manipulation of the small intestine in rats. Peritoneal lavage fluid, plasma, and jejunal segments were collected at several time points to determine inflammatory mediators in fasted rats and rats fed a lipid-rich or control nutrition. Gastrointestinal transit was measured 24 hours after surgery. RESULTS: Administration of lipid-rich nutrition markedly reduced the manipulation-induced local inflammatory response compared to rats treated with control nutrition. The intervention with lipid-rich nutrition significantly reduced plasma levels of rat mast cell protease-II (P < 0.05) and peritoneal levels of tumor necrosis factor-alpha (P < 0.01) and interleukin-6 (P < 0.05). Furthermore, the influx of neutrophils, expressed as tissue level myeloperoxidase was significantly prevented by lipid-rich nutrition (P < 0.05). Above all administration of lipid-rich enteral nutrition resulted in a significant improvement of gastrointestinal transit compared to control nutrition (P < 0.05). Blocking of cholecystokinin-receptors prevented the anti-inflammatory and motility promoting effect of lipid-rich feeding. CONCLUSION: Our data demonstrate that nutritional stimulation of the autonomic nervous system with enteral lipids reduces postoperative ileus by inhibition of inflammation. Clinically, lipid-rich enteral nutrition may be a new therapeutic option in the treatment of postoperative ileus.

Postshock intervention with high-lipid enteral nutrition reduces inflammation and tissue damage.

OBJECTIVE: To investigate the effects of high-lipid enteral nutrition in a setting of developing inflammation and tissue damage. BACKGROUND: An excessive inflammatory response following severe trauma is associated with poor clinical outcome. Currently, therapies directed at attenuation of an ongoing inflammatory cascade are lacking. Administration of high-lipid enteral nutrition before hemorrhagic shock has been shown to effectively inhibit early and late proinflammatory cytokines by activation of the autonomic nervous system via cholecystokinin (CCK)-receptors. METHODS: A rat model of hemorrhagic shock was used in which animals were either fasted or treated with high-lipid or control low-lipid enteral nutrition. CCK-receptor antagonists were administered before feeding. Tissues and plasma were collected to assess inflammation and intestinal integrity. RESULTS: Administration of high-lipid enteral nutrition after shock reduced plasma interferon-gamma (IFN-gamma) significantly in comparison with those in low-lipid-treated and fasted animals (P < 0.01 and P < 0.001, respectively). Also, interleukin (IL)-10 levels in plasma were decreased in comparison with those in fasted animals (P < 0.001). Enterocyte damage, expressed as circulating ileal lipid-binding protein (ILBP), was prevented by early high-lipid nutrition in comparison with that in low-lipid-treated and fasted animals (P = 0.05 and P < 0.001, respectively). Furthermore, high-lipid feeding preserved intestinal integrity in comparison with that observed in low-lipid-treated and fasted animals, as assessed by bacterial translocation (BT) to distant organs (P < 0.05 and P < 0.001, respectively) and ileal permeability to horseradish peroxidase (HRP) (P = 0.05 and P < 0.001, respectively). The protective effects of high-lipid intervention were nullified by CCK-receptor antagonists (IFN-gamma; IL-10; BT; and HRP; P < 0.05). CONCLUSION: High-lipid enteral nutrition given postshock reduces inflammation and preserves tissue integrity via a CCK-receptor-dependent mechanism. These findings implicate that intervention with high-lipid enteral nutrition following events such as severe trauma is a potential therapy to attenuate the developing inflammatory response.

Intestinal-FABP and liver-FABP: Novel markers for severe abdominal injury.

OBJECTIVES: Fatty acid-binding proteins (FABPs) have relatively high tissue concentrations and low plasma concentrations and are released into the circulation following organ injury. We explored the utility of intestinal-(I)-FABP and liver-(L)-FABP for the diagnosis of abdominal injury in patients with multiple trauma. METHODS: This prospective study included 102 trauma patients and 30 healthy volunteers. Plasma I-FABP and L-FABP levels were measured in the emergency department (ED) by enzyme-linked immunosorbent assay (ELISA). Forty-one patients suffered from serious or severe abdominal trauma (Abbreviated Injury Score [AIS] code "ai" for abdominal injury, AISai > or = 3) and nine were moderately abdominally injured (AISai < 3). Fifty-two had no abdominal injury. RESULTS: Median I-FABP and L-FABP levels in the AISai > or = 3 group (516 pg/mL and 135 ng/mL, respectively) were significantly higher compared to the AISai < 3 group (154 pg/mL and 13 ng/mL, respectively) or those without abdominal injury (207 pg/mL and 21 ng/mL, respectively) or normal controls (108 pg/mL and 13 ng/mL, respectively). The cutoff to distinguish the ai > or = 3 is 359 pg/mL for I-FABP and 54 ng/mL for L-FABP, with 93% specificity and 75% sensitivity for I-FABP and 93% and 82% for L-FABP, respectively. CONCLUSIONS: High I-FABP and L-FABP levels correlate with relevant severity of abdominal tissue damage in patients with multiple trauma. I-FABP and L-FABP could be useful as markers for the early detection of significant abdominal injury in acute multiple trauma and identify patients who require rapid intervention.

Intestinal cytoskeleton degradation precedes tight junction loss following hemorrhagic shock.

Hemorrhagic shock (HS) leads to intestinal barrier loss, causing systemic inflammation, which in turn can ultimately lead to multiorgan dysfunction syndrome. Barrier function is based on tight junctions (TJs) between intact epithelial cells. These TJs are anchored in the cell via the filamentous actin (F-actin) cytoskeleton. We hypothesize that HS causes hypoperfusion, leading to loss of F-actin, via activation of actin-depolymerizing factor/cofilin (AC), and consequently TJ loss. This study is aimed at unraveling the changes in cytoskeleton and TJ integrity after HS in organs commonly affected in multiorgan dysfunction syndrome (liver, kidney, and intestine) and to elucidate the events preceding cytoskeleton loss. Adult rats were subjected to a nonlethal HS and sacrificed, along with unshocked controls, at 15, 30, 60, and 90 min after induction of shock. Cytoskeleton, TJ integrity loss, and its consequences were studied by assessment of globular actin, F-actin, AC, zonula occludens protein 1, claudin 3, and bacterial translocation. In the liver and kidney, TJ and the F-actin cytoskeleton remained intact at all time points studied. However, in the intestine, significant loss of F-actin and increase of globular actin was seen from 15 min after shock. This change preceded statistically significant loss of the TJ proteins claudin 3 and zonula occludens protein 1, which were observed starting at 60 min after induction of shock (P < 0.05 vs. controls). Early after induction of shock (15 and 30 min) the nonactive AC (phosphorylated AC) in the intestine was significantly decreased (by 21% and 27%, P < 0.05 vs. control), whereas total AC remained constant, reflecting an increase in activated AC in the intestine from 15 min after shock. Bacterial translocation to mesenteric lymph nodes, liver, and spleen was present from 30 min after shock. This study shows for the first time that HS results in AC activation, selective intestinal actin cytoskeleton disruption, and TJ loss very early after the onset of shock. Loss of this intestinal barrier results in translocation of toxins and bacteria, which enhances inflammation and leads to infections.