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Background Esophageal adenocarcinoma (EAC) is a molecularly heterogeneous disease with poor prognosis that is rising rapidly in incidence. We aimed to demonstrate specific binding by a peptide heterodimer to Barrett’s neoplasia in human subjects. Methods Peptide monomers specific for EGFR and ErbB2 were arranged in a heterodimer configuration and labeled with IRDye800. This near-infrared (NIR) contrast agent was topically administered to patients with Barrett’s esophagus (BE) undergoing either endoscopic therapy or surveillance. Fluorescence images were collected using a flexible fiber accessory passed through the instrument channel of an upper gastrointestinal endoscope. Fluorescence images were collected from 31 BE patients. A deep learning model was used to segment the target (T) and background (B) regions. Results The mean target-to-background (T/B) ratio was significantly greater for high grade dysplasia (HGD) and EAC versus BE, low grade dysplasia (LGD), and squamous epithelium. At a T/B ratio of 1.5, sensitivity and specificity of 94.1 % and 92.6 %, respectively, were achieved for the detection of Barrett’s neoplasia with an area under the curve of 0.95. No adverse events attributed to the heterodimer were found. EGFR and ErbB2 expression were validated in the resected specimens. Conclusions This “first-in-human” clinical study demonstrates the feasibility of detection of early Barrett’s neoplasia using a NIR-labeled peptide heterodimer.

Supplementary Figure S2 from Phase IIa Clinical Trial of Curcumin for the Prevention of Colorectal Neoplasia

Reversion of morphological features. At the end of the 30-day incubation period in 1.5 mM calcium (alone or as part of Aquamin®) (a,c), colonoids were re-incubated in medium containing 0.15 mM calcium. Reversion to the undifferentiated phenotype was observed by Day 6 (b,d). Bar=100 μm.

Aquamin is a calcium-, magnesium-, and multiple trace element–rich natural product with colon polyp prevention efficacy based on preclinical studies. The goal of this study was to determine the effects of Aquamin on colonic microbial community and attendant metabolomic profile. Thirty healthy human participants were enrolled in a 90-day trial in which Aquamin (delivering 800 mg of calcium per day) was compared with calcium alone or placebo. Before and after the intervention, colonic biopsies and stool specimens were obtained. All 30 participants completed the study without serious adverse event or change in liver and renal function markers. Compared with pretreatment values, intervention with Aquamin led to a reduction in total bacterial DNA (P = 0.0001) and a shift in the microbial community measured by thetaYC (θYC; P = 0.0087). Treatment with calcium also produced a decline in total bacteria, but smaller than seen with Aquamin, whereas no reduction was observed with placebo in the colon. In parallel with microbial changes, a reduction in total bile acid levels (P = 0.0375) and a slight increase in the level of the short-chain fatty acid (SCFA) acetate in stool specimens (P < 0.0001) from Aquamin-treated participants were noted. No change in bile acids or SCFAs was observed with calcium or placebo. We conclude that Aquamin is safe and tolerable in healthy human participants and may produce beneficial alterations in the colonic microbial community and the attendant metabolomic profile. Because the number of participants was small, the findings should be considered preliminary.

Perspective on this Article from Chromoendoscopy Detects More Adenomas than Colonoscopy Using Intensive Inspection without Dye Spraying

Microbial variability - intra- and inter-subject differences.

The distribution of Phyla based on sample type (all samples).

A complete list of elements detected in Aquamin® (Mineral composition).

Metabolomic (Bile acids and SCFA) profile of colon biopsies.

Demographic characteristics of the participant population.

SUPPLEMENTAL MATERIALS AND METHODS. i) Histology and immunohistology. ii) Confocal fluorescence microscopy. iii) Morphometric analysis. iv) Scanning electron microscopy (SEM) and transmission electron microscopy TEM). v) Differential proteomic analysis.

The microbiome has been implicated in the development of colorectal cancer and inflammatory bowel diseases. The specific traits of these diseases vary along the axis of the digestive tract. Further, variation in the structure of the gut microbiota has been associated with both diseases. We profiled the microbiota of the healthy proximal and distal mucosa and lumen to better understand how bacterial populations vary along the colon. We used a two-colonoscope approach to sample proximal and distal mucosal and luminal contents from the colons of 20 healthy subjects that had not undergone any bowel preparation procedure. The biopsies and home-collected stool were subjected to 16S rRNA gene sequencing, and random forest classification models were built using taxa abundance and location to identify microbiota specific to each site. The right mucosa and lumen had the most similar community structures of the five sites we considered from each subject. The distal mucosa had higher relative abundance of Finegoldia, Murdochiella, Peptoniphilus, Porphyromonas, and Anaerococcus. The proximal mucosa had more of the genera Enterobacteriaceae, Bacteroides, and Pseudomonas. The classification model performed well when classifying mucosal samples into proximal or distal sides (AUC = 0.808). Separating proximal and distal luminal samples proved more challenging (AUC = 0.599), and specific microbiota that differentiated the two were hard to identify. By sampling the unprepped colon, we identified distinct bacterial populations native to the proximal and distal sides. Further investigation of these bacteria may elucidate if and how these groups contribute to different disease processes on their respective sides of the colon. Cancer Prev Res; 11(7); 393–402. ©2018 AACR.

Down-regulated proteins and associated pathways (by significantly down-regulated proteins)

Perspective on This Article from Phase IIa Clinical Trial of Curcumin for the Prevention of Colorectal Neoplasia

PDF file - 95K, Flow Diagram of a Trial of Ginger Supplementation Over Four Weeks on Markers of Apoptosis, Proliferation and Differentiation in the Normal-Appearing Colorectal Mucosa of Individuals at Increased Risk of CRC

PDF file - 63K, Cell Cycle Biomarkers of Risk

Location and relative abundance of cancer-associated OTUs.

Perspective from Difluoromethylornithine Plus Sulindac for the Prevention of Sporadic Colorectal Adenomas: A Randomized Placebo-Controlled, Double-Blind Trial

Previous murine studies have demonstrated that dietary Aquamin, a calcium-rich, multi-mineral natural product, suppressed colon polyp formation and transition to invasive tumors more effectively than calcium alone when provided over the lifespan of the animals. In the current study, we compared calcium alone to Aquamin for modulation of growth and differentiation in human colon adenomas in colonoid culture. Colonoids established from normal colonic tissue were examined in parallel. Both calcium alone at 1.5 mmol/L and Aquamin (provided at 1.5 mmol/L calcium) fostered differentiation in the adenoma colonoid cultures as compared with control (calcium at 0.15 mmol/L). When Aquamin was provided at an amount delivering 0.15 mmol/L calcium, adenoma differentiation also occurred, but was not as complete. Characteristic of colonoids undergoing differentiation was a reduction in the number of small, highly proliferative buds and their replacement by fewer but larger buds with smoother surface. Proliferation marker (Ki67) expression was reduced and markers of differentiation (CK20 and occludin) were increased along with E-cadherin translocalization to the cell surface. Additional proteins associated with differentiation/growth control [including histone-1 family members, certain keratins, NF2 (merlin), olfactomedin-4 and metallothioneins] were altered as assessed by proteomics. Immunohistologic expression of NF2 was higher with Aquamin as compared with calcium at either concentration. These findings support the conclusions that (i) calcium (1.5 mmol/L) has the capacity to modulate growth and differentiation in large human colon adenomas and (ii) Aquamin delivering 0.15 mmol/L calcium has effects on proliferation and differentiation not observed when calcium is used alone at this concentration. Cancer Prev Res; 11(7); 413–28. ©2018 AACR.

Up-regulated proteins and associated pathways (by significantly up-regulated proteins).

PDF file - 65K, Adverse Events (AE)Reported by Participant

Supplemental Tables/Figures legends

The distribution of Genera based on sample type (all samples).

The evaluation of eicosanoid metabolites in colon tissue.

SUPPLEMENT TABLE 1: Aquamin® Mineral Analysis. SUPPLEMENT TABLE 2: ANTIBODIES used in the study.

Perspective on This Article from Microsatellite Instability and DNA Mismatch Repair Protein Deficiency in Lynch Syndrome Colorectal Polyps

Higher magnification images of the immunostained colonoid sections. Immunohistology (as shown in Figures 3 and 4). At the end of the 30-day incubation period, colonoids were examined under light-microscopy after immunostaining for CK20, E-cadherin, occluding, cleaved caspase-3 and NF-2. Bars=50 μm.

Adenoma colonoid expansion. Individual colonoids from each of the three adenomas were examined under phase-contrast microscopy after 8 and 13 days in culture (under each condition) and photographed. Photoshop CS6 image analysis tool was used to assess the surface area encompassed by individual colonoids and the difference in colonoid size between day-8 and day-13 was used to calculate the growth index (net change between the two time-points). Values shown are means and standard deviations. The number of individual colonoids assessed ranged from n=250 to n=424 for adenoma 282. For adenoma 590, colonoids ranged from n=53 to n=77. For adenoma 584, numbers ranged from n=15 to n=111. Statistical significance was assessed by ANOVA followed by student t-test (two-tailed) for unpaired data. Asterisks indicate significance at p

INTRODUCTION: In biomarker-driven clinical trials, translational strategies typically involve moving findings from animal experiments to human trials. Typically, the translation is static, using a fixed model derived from animal experiments for the duration of the trial. But Bayesian designs, capable of incorporating information external to the experiment, provide a dynamic translational strategy. The current article demonstrates an example of such a dynamic Bayesian strategy in a clinical trial. METHODS: This study explored the effect of a personalized dose of fish oil for reducing prostaglandin E(2), an inflammatory marker linked to colorectal cancer. A Bayesian design was implemented for the dose-finding algorithm that adaptively updated a dose–response model derived from a previously completed the animal study during the clinical trial. In the initial stages of the trial, the dose–response model parameters were estimated from the rodent data. The model was updated following a Bayesian algorithm after data on every ten to 15 subjects were obtained until the model stabilized. Subjects were enrolled in the study between 2013 and 2015, and the data analysis was carried out in 2016. RESULTS: Three dosing models were used for groups of 16, 15, and 15 subjects. The mean target dose significantly decreased from 6.63 g/day (Model 1) to 4.06 g/day (Model 3) (p=0.001). Compared with the static strategy of dosing with a single model, the dynamic modeling reduced the dose significantly by about 1.38 g/day, on average. CONCLUSIONS: A Bayesian design was effective in adaptively revising the dosing algorithm, resulting in a lower pill burden. TRIAL REGISTRATION: This study is registered at www.clinicaltrials.gov NCT01860352.

BACKGROUND: The intestinal microbiome is an important determinant of inflammatory balance in the colon that may affect response to dietary agents. OBJECTIVE: This is a secondary analysis of a clinical trial, the Fish Oil Study, to determine whether interindividual differences in colonic bacteria are associated with variability in the reduction of colonic prostaglandin E(2) (PGE(2)) concentrations after personalized supplementation with ω-3 (n–3) fatty acids. METHODS: Forty-seven healthy adults (17 men, 30 women, ages 26–75 y) provided biopsy samples of colonic mucosa and luminal stool brushings before and after personalized ω-3 fatty acid supplementation that was based on blood fatty acid responses. Samples were analyzed using 16S ribosomal RNA sequencing. The data analyses focused on changes in bacterial community diversity. Linear regression was used to evaluate factors that predict a reduction in colonic PGE(2). RESULTS: At baseline, increased bacterial diversity, as measured by the Shannon and Inverse Simpson indexes in both biopsy and luminal brushing samples, was positively correlated with dietary fiber intakes and negatively correlated with fat intakes. Dietary supplementation with ω-3 fatty acids increased the Yue and Clayton community dis-similarity index between the microbiome in luminal brushings and colon biopsy samples post-supplementation (P = 0.015). In addition, there was a small group of individuals with relatively high Prevotella abundance who were resistant to the anti-inflammatory effects of ω-3 fatty acid supplementation. In linear regression analyses, increases in diversity of the bacteria in the luminal brushing samples, but not in the biopsy samples, were significant predictors of lower colonic PGE(2) concentrations post-supplementation in models that included baseline PGE(2), baseline body mass index, and changes in colonic eicosapentaenoic acid–to–arachidonic acid ratios. The changes in bacterial diversity contributed to 6–8% of the interindividual variance in change in colonic PGE(2) (P = 0.001). CONCLUSIONS: Dietary supplementation with ω-3 fatty acids had little effect on intestinal bacteria in healthy humans; however, an increase in diversity in the luminal brushings significantly predicted reductions in colonic PGE(2). This trial was registered at www.clinicaltrials.gov as NCT 01860352.

This study evaluated changes in fatty acids from sera, red blood cells and colonic biopsies from a phase Ib clinical trial of personalized ω-3 fatty acid dosing in 47 healthy volunteers. The trial aimed to reduce colonic prostaglandin E(2) (PGE(2)), a pro-inflammatory product of arachidonic acid (AA) oxidation. The personalized doses ranged 2-10 grams/day (54% eicosapentaenoic acid, EPA, 24% other ω-3 fatty acids). In colon, increases in ω-3 highly unsaturated fatty acids (HUFA) and EPA:AA ratios each were correlated with decreases in PGE(2). Changes in either colonic EPA:AA ratios or ω-3 HUFA were significantly correlated with changes in the same fatty acid measures in red blood cells or serum. The only blood-based measure significantly correlated with changes in colonic PGE(2) was change in red blood cell ω-3 HUFA (ρ = − 0.39), and the increase in red blood cell ω-3 HUFA was significantly greater in participants who had at least a median reduction in colonic PGE(2) versus those who did not. In summary, fatty acid changes in blood did reflect fatty acid changes in the colon, but additional factors will be needed for optimizing dosing models that seek to predict the anti-inflammatory effects of ω-3 fatty acids on the colon.

The overall goal of this study was to determine whether Aquamin®, a calcium-, magnesium-, trace element-rich, red algae-derived natural product, would alter the expression of proteins involved in growth-regulation and differentiation in colon. Thirty healthy human subjects (at risk for colorectal cancer) were enrolled in a three-arm, 90-day interventional trial. Aquamin® was compared to calcium alone and placebo. Before and after the interventional period, colonic biopsies were obtained. Biopsies were evaluated by immunohistology for expression of Ki67 (proliferation marker) and for CK20 and p21 (differentiation markers). Tandem mass tag-mass spectrometry-based detection was used to assess levels of multiple proteins. As compared to placebo or calcium, Aquamin® reduced the level of Ki67 expression and slightly increased CK20 expression. Increased p21 expression was observed with both calcium and Aquamin®. In proteomic screen, Aquamin® treatment resulted in many more proteins being upregulated (including pro-apoptotic, cytokeratins, cell–cell adhesion molecules, and components of the basement membrane) or downregulated (proliferation and nucleic acid metabolism) than placebo. Calcium alone also altered the expression of many of the same proteins but not to the same extent as Aquamin®. We conclude that daily Aquamin® ingestion alters protein expression profile in the colon that could be beneficial to colonic health.

Background Pancreatic ductal adenocarcinoma (PDAC) has low ( Methods For subcutaneous efficacy, 5-6-week-old female nude mice (n=5/group) were injected with KPC-Luc cells and randomized to: 1) vehicle (PBS), 2) Gem plus HCQ, 3) Gem plus Par, and 4) Gem, HCQ, and Par once tumors were palpable. Gem and Par (twice weekly) were administered via intraperitoneal injection. HCQ was given orally (daily). For orthotropic efficacy and single cell analysis, female C57BL/6J mice (n=6/group) were injected with 2×105 KPC-Luc cells into the pancreas tail. On day 5, animals were randomized to 1) PBS and 2) combined Gem/HCQ/Par as above. Tumors were analyzed via bioluminescent imaging. After 15 days, animals were euthanized, tumors were weighed and dissociated into single cells. High viability samples were used to generate scRNA-Seq libraries using 10X genomics droplet approach. Results Gem, HCQ, and Par significantly (p Conclusion HCQ and Par enhance the efficacy of Gem in two mice PDAC models. Single cell transcriptome analyses revealed the combination treatment promoted immune shifts in the PDAC TME. Effects of Par and HCQ and standard chemotherapy drugs, Gem and nab-paclitaxel are being studied in an ongoing clinical trial (NCT04524702). Citation Format: Purnachandra Nagaraju Ganji, Beena Elizabeth Thomas, Maggie Phillips, Cameron Herting, Amanda Ruggieri, Jessica Millian Keilson, Michael Kim Turgeon, Sisira Saraswatula, William Pilcher, Gregory B. Lesinski, Manoj Bhasin, Bassel F. El-Rayes. Paricalcitol, hydroxychloroquine and gemcitabine promote antitumor effects and modulate immune profile in pancreatic ductal adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1059.

Background: Esophageal adenocarcinoma is a molecularly heterogeneous disease that is rising rapidly in incidence and has a poor prognosis. Current methods of endoscopic surveillance in patients with Barrett’s esophagus (BE) using white light illumination are not sensitive to pre-malignant lesions that are flat in appearance and patchy in distribution. We aim to demonstrate specific binding by a peptide heterodimer to Barrett’s neoplasia in human subjects. Methods: Peptide monomers specific for EGFR and ErbB2 were arranged in a heterodimer configuration and labeled with IRDye800. The near-infrared (NIR)-labeled heterodimer was synthesized using current good manufacturing practices (cGMP) methods and performed pharmacology/toxicology study in animals using good laboratory practices (GLP). The NIR contrast agent was topically administered in the distal esophagus of patients with history of neoplastic BE undergoing endoscopic therapy or surveillance. Fluorescence images were collected using a flexible fiber accessory passed through the instrument channel of an upper endoscope. Fluorescence images were collected from n = 31 BE patients, and a deep learning model was used to segment the target (T) and background (B) regions to calculate the T/B ratio. Findings: Between August 2018 and November 2020, 25 human subjects were enrolled for safety study and 31 patients for either evaluation or therapy of Barrett’s neoplasia were recruited for imaging study. No adverse events attributed to the heterodimer were found. The mean T/B ratio in patients for HGD and EAC were significantly greater than that for BE with low grade dysplasia, without dysplasia, or squamous mucosa. At a T/B ratio of 1.5, 94.1% sensitivity and 92.6% specificity for detection of Barrett’s neoplasia was achieved with an AUC = 0.95. The presence of Barrett’s neoplasia was validated by pathological assessment of resected specimens. Interpretation: This “first-in-human” clinical study demonstrates feasibility to detect early Barrett’s neoplasia using a NIR-labeled peptide heterodimer. Trial Registration: This study was registered online at ClinicalTrials.gov (NCT03643068) Funding National Institutes of Health. Declaration of Interest: Authors (JC, TDW) are inventors on patents filed by the University of Michigan on the peptide heterodimer used in this study. Author (EJS) is an inventor on patents filed by the University of Washington on the multimodal scanning fiber endoscope (mmSFE) used in this study. The other authors disclose no conflicts. Ethical Approval: All study protocols were reviewed and approved by the Institutional Review Board (IRB) at Michigan Medicine

Previous murine studies have demonstrated that dietary Aquamin, a calcium-rich, multi-mineral natural product, suppressed colon polyp formation and transition to invasive tumors more effectively than calcium alone when provided over the lifespan of the animals. In the current study, we compared calcium alone to Aquamin for modulation of growth and differentiation in human colon adenomas in colonoid culture. Colonoids established from normal colonic tissue were examined in parallel. Both calcium alone at 1.5 mmol/L and Aquamin (provided at 1.5 mmol/L calcium) fostered differentiation in the adenoma colonoid cultures as compared with control (calcium at 0.15 mmol/L). When Aquamin was provided at an amount delivering 0.15 mmol/L calcium, adenoma differentiation also occurred, but was not as complete. Characteristic of colonoids undergoing differentiation was a reduction in the number of small, highly proliferative buds and their replacement by fewer but larger buds with smoother surface. Proliferation marker (Ki67) expression was reduced and markers of differentiation (CK20 and occludin) were increased along with E-cadherin translocalization to the cell surface. Additional proteins associated with differentiation/growth control [including histone-1 family members, certain keratins, NF2 (merlin), olfactomedin-4 and metallothioneins] were altered as assessed by proteomics. Immunohistologic expression of NF2 was higher with Aquamin as compared with calcium at either concentration. These findings support the conclusions that (i) calcium (1.5 mmol/L) has the capacity to modulate growth and differentiation in large human colon adenomas and (ii) Aquamin delivering 0.15 mmol/L calcium has effects on proliferation and differentiation not observed when calcium is used alone at this concentration. Cancer Prev Res; 11(7); 413–28. ©2018 AACR.

This clinical trial developed a personalized dosing model for reducing prostaglandin E2 (PGE2) in colonic mucosa using ω-3 fatty acid supplementation. The model utilized serum eicosapentaenoic acid (EPA, ω-3):arachidonic acid (AA, ω-6) ratios as biomarkers of colonic mucosal PGE2 concentration. Normal human volunteers were given low and high ω-3 fatty acid test doses for 2 weeks. This established a slope and intercept of the line for dose versus serum EPA:AA ratio in each individual. The slope and intercept was utilized to calculate a personalized target dose that was given for 12 weeks. This target dose was calculated on the basis of a model, initially derived from lean rodents, showing a log-linear relationship between serum EPA:AA ratios and colonic mucosal PGE2 reduction. Bayesian methods allowed addition of human data to the rodent model as the trial progressed. The dosing model aimed to achieve a serum EPA:AA ratio that is associated with a 50% reduction in colonic PGE2. Mean colonic mucosal PGE2 concentrations were 6.55 ng/mg protein (SD, 5.78) before any supplementation and 3.59 ng/mg protein (SD, 3.29) after 12 weeks of target dosing. In secondary analyses, the decreases in PGE2 were significantly attenuated in overweight and obese participants. This occurred despite a higher target dose for the obese versus normal weight participants, as generated by the pharmacodynamic predictive model. Large decreases also were observed in 12-hydroxyicosatetraenoic acids, and PGE3 increased substantially. Future biomarker-driven dosing models for cancer prevention therefore should consider energy balance as well as overall eicosanoid homeostasis in normal tissue. Cancer Prev Res; 10(12); 729–37. ©2017 AACR.

Preliminary single-institution data suggest that fluorescence in situ hybridization (FISH) may be useful for detecting high-grade dysplasia (HGD) and esophageal adenocarcinoma (EA) in patients with Barrett’s esophagus (BE). This multicenter study aims to validate the measurement of polysomy (gain of at least two loci) by FISH as a way to discriminate degrees of dysplasia in BE specimens. Tissue specimens were collected from four different hospitals and read by both the local pathology department (“Site diagnosis”) and a single central pathologist (“Review diagnosis”) at a separate institution. The specimens then underwent FISH analysis using probes 8q24 (MYC), 9p21 (CDKN2A), 17q12 (ERBB2), and 20q13 (ZNF217) for comparison. A total of 46 non-BE, 42 non-dysplastic specialized intestinal metaplasia (SIM), 23 indefinite-grade dysplasia (IGD), 10 low-grade dysplasia (LGD), 29 HGD, and 42 EA specimens were analyzed. We found that polysomy, as detected by FISH, was the predominant chromosomal abnormality present as dysplasia increased. Polysomy was also the best predictor for the presence of dysplasia or EA when comparing its area under the curve to that of other FISH abnormalities. We observed that if at least 10% of cells had polysomy within a specimen, the FISH probe was able to differentiate between EA/HGD and the remaining pathologies with a sensitivity of 80% and a specificity of 88%. This study demonstrates that using FISH to determine the percentage of cells with polysomy can accurately and objectively aid in the diagnosis of HGD/EA in BE specimens.

Aquamin is a calcium-, magnesium-, and multiple trace element–rich natural product with colon polyp prevention efficacy based on preclinical studies. The goal of this study was to determine the effects of Aquamin on colonic microbial community and attendant metabolomic profile. Thirty healthy human participants were enrolled in a 90-day trial in which Aquamin (delivering 800 mg of calcium per day) was compared with calcium alone or placebo. Before and after the intervention, colonic biopsies and stool specimens were obtained. All 30 participants completed the study without serious adverse event or change in liver and renal function markers. Compared with pretreatment values, intervention with Aquamin led to a reduction in total bacterial DNA (P = 0.0001) and a shift in the microbial community measured by thetaYC (θYC; P = 0.0087). Treatment with calcium also produced a decline in total bacteria, but smaller than seen with Aquamin, whereas no reduction was observed with placebo in the colon. In parallel with microbial changes, a reduction in total bile acid levels (P = 0.0375) and a slight increase in the level of the short-chain fatty acid (SCFA) acetate in stool specimens (P < 0.0001) from Aquamin-treated participants were noted. No change in bile acids or SCFAs was observed with calcium or placebo. We conclude that Aquamin is safe and tolerable in healthy human participants and may produce beneficial alterations in the colonic microbial community and the attendant metabolomic profile. Because the number of participants was small, the findings should be considered preliminary.

This study evaluated whether mRNA expression of major genes regulating formation of prostaglandin (PG)E(2) in the colon and colonic fatty acid concentrations are associated with the reduction in colonic mucosal PGE(2) after dietary supplementation with omega-3 (ω-3) fatty acids. Supplementation with ω-3 fatty acids was done for 12 weeks using personalized dosing that was expected to reduce colonic PGE(2) by 50%. In stepwise linear regression models, the ω-3 fatty acid dose and subject BMI explained 16.1% of the inter-individual variability in the fold change of colonic PGE(2) post-supplementation. Increases in mRNA gene expression after supplementation were, however, modest and were not associated with changes in PGE(2). When baseline expression of PTGS1, PTGS2 and HPGD genes was included in the linear regression model containing dose and BMI, only PTGS2, the gene coding for the inducible form cyclooxygenase, was a significant predictor. Higher relative expression of PTGS2 predicted greater decreases in colonic PGE(2), accounting for an additional 13.6% of the inter-individual variance. In the final step of the regression model, greater decreases in total colonic fatty acid concentrations predicted greater decreases in colonic PGE(2), contributing to an additional 18.7% of the variance. Overall, baseline BMI, baseline expression of PTGS2 and changes in colonic total fatty acids together accounted for 48% of the inter-individual variability in the change in colonic PGE(2). This is consistent with biochemical data showing that fatty acids which are not substrates for cyclooxygenases can activate cyclooxygenase-2 allosterically. Further clinical trials are needed to elucidate the factors that regulate the fatty acid milieu of the human colon and how this interacts with key lipid metabolizing enzymes. Given the central role of PGE(2) in colon carcinogenesis, these pathways may also impact on colon cancer prevention by other dietary and pharmacological approaches.

Background and study aims: To demonstrate the clinical use of a multimodal endoscope with a targeted fluorescently labeled peptide for quantitative detection of Barrett’s neoplasia. Patients and methods: We studied 50 patients with Barrett’s esophagus using a prototype multimodal endoscope with a fluorescently labeled peptide. Co-registered fluorescence and reflectance images were converted to ratios to correct for differences in distance and geometry over the image field of view. The ratio images were segmented using a unique threshold that maximized the variance between high and low intensities to localize regions of high grade dysplasia (HGD) and esophageal adenocarcinoma (EAC). Results: Early neoplasia (HGD and EAC) was identified with 94 % specificity and 96 % positive predictive value at a threshold of 1.49. The mean results for HGD and EAC were significantly greater than those for squamous/Barrett’s esophagus and low grade dysplasia by one-way analysis of variance (ANOVA). The receiver operator characteristic curve for detection of early neoplasia had an area under the curve of 0.884. No adverse events associated with the endoscope or peptide were found. Conclusion: A multimodal endoscope can quantify fluorescence images from targeted peptides to localize early Barrett’s neoplasia. (ClinicalTrials.gov number NCT01630798.)

Systemic exposures to intestinal bacteria may play a role in the etiology of the chronic, low-grade inflammation that is associated with western diets. Production of lipopolysaccharide-binding protein (LBP) is one biomarker of increased exposures to intestinal bacteria. This study evaluated whether changes in diet quality could affect serum LBP.This was a randomized, controlled trial of Mediterranean and Healthy Eating diets over 6 months in 120 healthy subjects at increased risk of colon cancer. Blood samples obtained before and after intervention were analyzed for LBP, branched-chain fatty acids characteristic of intestinal bacteria, micronutrients and cytokines. Data were analyzed for changes in LBP over time and for predictors of LBP.Serum concentrations of branched-chain bacterial fatty acids declined significantly in both diet groups. However, there was no significant change in mean serum LBP concentrations with either diet intervention. In serum, LBP was positively associated with CRP and negatively associated with carotenoids both before and after intervention. After intervention, LBP was predicted positively by both CRP and bacterial fatty acid concentrations in serum, and negatively by serum carotenoids and the ω3/ω6 fatty acid ratio. This model accounted for 30 % of the inter-individual variation in serum LBP after intervention.These results indicate that dietary intervention over 6 months was insufficient to alter serum LBP. The relationships with inflammation-related markers, however, indicate that anti-inflammatory strategies other than changes in diet quality, such as weight loss or improved fitness, may have more potential for reducing systemic markers of LPS exposures in well-nourished populations.

Background Relatively high serum carotenoid levels are associated with reduced risks of chronic diseases, but inter-individual variability in serum carotenoid concentrations is modestly explained by diet. The bacterial community in the colon could contribute to the bioaccessibility of carotenoids by completing digestion of plant cells walls and by modulating intestinal permeability. Objective To evaluate whether colonic bacterial composition is associated with serum and colon carotenoid concentrations. Design The study was a randomized dietary intervention trial in healthy individuals who were at increased risk of colon cancer. Colon mucosal biopsy samples were obtained before and after 6 months of intervention without prior preparation of the bowels. Participants/setting Participants were recruited from Ann Arbor, MI, and nearby areas from July 2007 to November 2010. Biopsy data were available from 88 participants at baseline and 82 participants after 6 months. Methods Study participants were randomized to counseling for either a Mediterranean diet or a Healthy Eating diet for 6 months. Results At baseline, bacterial communities in biopsy samples from study participants in the highest vs the lowest tertile of total serum carotenoid levels differed by several parameters. Linear discriminant analysis effect size identified 11 operational taxonomic units that were significantly associated with higher serum carotenoid levels. In linear regression analyses, three of these accounted for an additional 12% of the variance in serum total carotenoid concentrations after including body mass index, smoking, and dietary intakes in the model. These factors together explained 36% of the inter-individual variance in serum total carotenoid concentrations. The bacterial community in the colonic mucosa, however, was resistant to change after dietary intervention with either a Mediterranean diet or Healthy Eating diet, each of which doubled fruit and vegetable intakes. Conclusions The colonic mucosal bacterial community was associated with serum carotenoid concentrations at baseline but was not appreciably changed by dietary intervention.