Prebiotic proanthocyanidins inhibit bile reflux-induced esophageal adenocarcinoma through reshaping the gut microbiome and esophageal metabolome

The gut and local esophageal microbiome progressively shift from healthy commensal bacteria to inflammation-linked pathogenic bacteria in patients with gastroesophageal reflux disease, Barrett's esophagus, and esophageal adenocarcinoma (EAC). However, mechanisms by which microbial communities and metabolites contribute to reflux-driven EAC remain incompletely understood and challenging to target. Herein, we utilized a rat reflux-induced EAC model to investigate targeting the gut microbiome-esophageal metabolome axis with cranberry proanthocyanidins (C-PAC) to inhibit EAC progression. Sprague-Dawley rats, with or without reflux induction, received water or C-PAC ad libitum (700 μg/rat/day) for 25 or 40 weeks. C-PAC exerted prebiotic activity abrogating reflux-induced dysbiosis and mitigating bile acid metabolism and transport, culminating in significant inhibition of EAC through TLR/NF-κB/TP53 signaling cascades. At the species level, C-PAC mitigated reflux-induced pathogenic bacteria (Streptococcus parasanguinis, Escherichia coli, and Proteus mirabilis). C-PAC specifically reversed reflux-induced bacterial, inflammatory, and immune-implicated proteins and genes, including Ccl4, Cd14, Crp, Cxcl1, Il6, Il1b, Lbp, Lcn2, Myd88, Nfkb1, Tlr2, and Tlr4, aligning with changes in human EAC progression, as confirmed through public databases. C-PAC is a safe, promising dietary constituent that may be utilized alone or potentially as an adjuvant to current therapies to prevent EAC progression through ameliorating reflux-induced dysbiosis, inflammation, and cellular damage.

Cranberry Proanthocyanidins Mitigate Reflux-Induced Transporter Dysregulation in an Esophageal Adenocarcinoma Model

We recently reported that cranberry proanthocyanidins (C-PACs) inhibit esophageal adenocarcinoma (EAC) by 83% through reversing reflux-induced bacterial, inflammatory and immune-implicated proteins and genes as well as reducing esophageal bile acids, which drive EAC progression. This study investigated whether C-PACs' mitigation of bile reflux-induced transporter dysregulation mechanistically contributes to EAC prevention. RNA was isolated from water-, C-PAC- and reflux-exposed rat esophagi with and without C-PAC treatment. Differential gene expression was determined by means of RNA sequencing and RT-PCR, followed by protein assessments. The literature, coupled with the publicly available Gene Expression Omnibus dataset GSE26886, was used to assess transporter expression levels in normal and EAC patient biopsies for translational relevance. Significant changes in ATP-binding cassette (ABC) transporters implicated in therapeutic resistance in humans (i.e., Abcb1, Abcb4, Abcc1, Abcc3, Abcc4, Abcc6 and Abcc10) and the transport of drugs, xenobiotics, lipids, and bile were altered in the reflux model with C-PACs' mitigating changes. Additionally, C-PACs restored reflux-induced changes in solute carrier (SLC), aquaporin, proton and cation transporters (i.e., Slc2a1, Slc7a11, Slc9a1, Slco2a1 and Atp6v0c). This research supports the suggestion that transporters merit investigation not only for their roles in metabolism and therapeutic resistance, but as targets for cancer prevention and targeting preventive agents in combination with chemotherapeutics.

Improved in vitro Hemagglutination Assays Utilizing P-Type and Type 1 Uropathogenic Escherichia coli to Evaluate Bacterial Anti-Adhesion Activity of Cranberry Products

Cranberries have a long history of use in the prevention of urinary tract infections. Cranberry products vary in proanthocyanidin content, a compound implicated in preventing the adhesion of uropathogenic Escherichia coli (E. coli) to uroepithelial cells. Testing is routinely done by cranberry product formulators to evaluate in vitro bacterial anti-adhesion bioactivity, shelf-life, and potential efficacy of cranberry products for consumer use to maintain urinary tract health. Hemagglutination assays evaluate the anti-adhesion bioactivity of cranberry products by determining how effectively the products prevent agglutination of specific red blood cells with E. coli expressing P-type and Type 1 fimbriae. The current study sought to improve upon an established anti-adhesion assay method by expanding the number of E. coli strains used to broaden potential in vivo efficacy implications and presenting results using photomicrographic data to improve accuracy and build databases on products that are routinely tested. Different lots of cranberry powder ingredient and two formulated products were tested independently for anti-adhesion activity using the established method and the improved method. Positive harmonization of results on the same samples using rigorous controls was achieved and provides the substantiation needed for the cranberry industry to utilize the improved, rapid in vitro testing method to standardize cranberry products for sufficient anti-adhesion bioactivity and maintain consumer confidence.

Prebiotic proanthocyanidins inhibit bile reflux-induced esophageal adenocarcinoma through reshaping the gut microbiome and esophageal metabolome

The gut and local esophageal microbiome progressively shift from healthy commensal bacteria to inflammatory-linked pathogenic bacteria in patients with gastroesophageal reflux disease, Barrett's esophagus and esophageal adenocarcinoma (EAC). However, mechanisms by which microbial communities and metabolites contribute to reflux-driven EAC remain incompletely understood and challenging to target. Herein, we utilized a rat reflux-induced EAC model to investigate targeting the gut microbiome-esophageal metabolome axis with cranberry proanthocyanidins (C-PAC) to inhibit EAC progression. Sprague Dawley rats, with or without reflux-induction received water or C-PAC ad libitum (700 µg/rat/day) for 25 or 40 weeks. C-PAC exerted prebiotic activity abrogating reflux-induced dysbiosis, and mitigating bile acid metabolism and transport, culminating in significant inhibition of EAC through TLR/NF-κB/P53 signaling cascades. At the species level, C-PAC mitigated reflux-induced pathogenic bacteria (Clostridium perfringens, Escherichia coli, and Proteus mirabilis). C-PAC specifically reversed reflux-induced bacterial, inflammatory and immune-implicated proteins and genes including Ccl4, Cd14, Crp, Cxcl1, Il6, Il1β, Lbp, Lcn2, Myd88, Nfkb1, Tlr2 and Tlr4 aligning with changes in human EAC progression, as confirmed through public databases. C-PAC is a safe promising dietary constituent that may be utilized alone or potentially as an adjuvant to current therapies to prevent EAC progression through ameliorating reflux-induced dysbiosis, inflammation and cellular damage.

Abstract 1745: Targeting therapeutic resistance of esophageal adenocarcinoma through modulating the epithelial-to-mesenchymal transition via NFκB-mediated signaling

Esophageal adenocarcinoma (EAC) is the major subtype of esophageal cancer in Westernized countries, characterized by rising incidence and poor prognosis with a five-year survival rate less than 20%. Only 15% of EAC patients have a complete histopathological response to standard chemotherapy, indicating the urgent need to identify mechanisms associated with therapeutic resistance for improved therapeutic efficacy and patient outcomes. Herein, we performed transcriptional profiling utilizing tissues collected from EAC patients prior to treatment initiation. First, EAC patients (n=67) were stratified into 5 therapeutic response groups based on the changes in TNM pre- to post-treatment; second, bioinformatic approaches were utilized to identify molecular changes associated with response to treatment and patient survival. Third, we employed OE19 and OE33 human EAC cell lines to investigate the efficacy of cranberry proanthocyanidins (C-PAC), a promising anti-inflammatory and anti-cancer agent which shows synergistic effects with carboplatin in other cancer types, at mitigating molecular pathways which drive therapeutic resistance. Our therapeutic response data set revealed epithelial-mesenchymal transition (EMT) as a top pathway associated with differential response to therapy and patient survival. Subsequent gene-set enrichment analysis identified that EMT is significantly associated with NFκB and STAT3 signaling pathways, two nodes with documented proinflammatory roles in EAC progression. Deconvolution analysis was conducted further supporting EMT enrichment creates an immune-suppressive tumor microenvironment in EAC patients. Next, EAC cell viability, migration and interrogation of EMT signaling proteins were conducted following treatment with paclitaxel and carboplatin (chemo drugs) alone or in combination with C-PAC. Combination treatment of C-PAC and chemo drugs significantly inhibited EAC cell viability and migration capability, compared to cells treated with chemo drugs alone, with synergistic effects observed in OE33 cells. Moreover, combination treatment also significantly decreased NFκB1 expression and expressions of EMT markers and transcription factors (Snail, MMP-2, MMP-9, and Vimentin) whereas cells treated only with chemo drugs showed minimal modulation. Knockdown experiments of NFκB1 using RNA interference are underway to investigate the relationship between canonical NFκB1 signaling and EMT. Primary cell lines and organoids developed from isolated EAC patient tissues will also be used in the future to validate experimental findings. The results suggest C-PAC may be used as a safe and novel therapeutic strategy to improve chemotherapy efficacy targeting EAC.

Citation Format: Yun Zhang, Katherine M. Weh, Connor L. Howard, Jean-Jack Riethoven, Jennifer L. Clarke, Michelle P. Lee, Kiran H. Lagisetty, Jules Lin, Rishindra M. Reddy, Andrew C. Chang, Amy B. Howell, Laura A. Kresty. Targeting therapeutic resistance of esophageal adenocarcinoma through modulating the epithelial-to-mesenchymal transition via NFκB-mediated signaling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1745.

Proanthocyanidins mitigate bile acid-induced changes in GSTT2 levels in a panel of racially diverse patient-derived primary esophageal cell cultures

Persistent and symptomatic reflux of gastric and duodenal contents, known as gastroesophageal reflux disease (GERD), is the strongest risk factor for esophageal adenocarcinoma (EAC). Despite similar rates of GERD and other risk factors across racial groups, EAC progression disproportionately impacts Caucasians. We recently reported that elevated tissue levels of the detoxification enzyme GSTT2 in the esophagi of Blacks compared to Caucasians may contribute protection. Herein, we extend our research to investigate whether cranberry proanthocyanidins (C-PAC) mitigate bile acid-induced damage and GSTT2 levels utilizing a racially diverse panel of patient-derived primary esophageal cultures. We have shown that C-PACs mitigate reflux-induced DNA damage through GSTT2 upregulation in a rat esophageal reflux model, but whether effects are recapitulated in humans or differentially based on race remains unknown. We isolated normal primary esophageal cells from Black and Caucasian patients and assessed GSTT2 protein levels and cellular viability following exposure to a bile acid cocktail with and without C-PAC treatment. Constitutive GSTT2 levels were significantly elevated in Black (2.9-fold) compared to Caucasian patients, as were GSTT2 levels in Black patients with GERD. C-PAC treatment induced GSTT2 levels 1.6-fold in primary normal esophageal cells. GSTT2 induction by C-PAC was greatest in cells with constitutively low GSTT2 expression. Overall, C-PAC mitigated bile-induced reductions of GSTT2 and subsequent loss of cell viability regardless of basal GSTT2 expression or race. These data support that C-PAC may be a safe efficacious agent to promote epithelial fitness through GSTT2 induction and in turn protect against bile acid-induced esophageal injury.

Differences in Urinary Bacterial Anti-Adhesion Activity after Intake of Cranberry Dietary Supplements with Soluble versus Insoluble Proanthocyanidins

A number of clinical trials support the use of standardized cranberry supplement products for prevention of urinary tract infections; however, products that are not well-characterized for sufficient levels of bioactive components may contribute to negative clinical outcomes. Cranberry supplements for consumer use are not regulated and can be formulated different ways using cranberry juice, pomace or various combinations. This can lead to consumer confusion regarding effectiveness of individual products. The current study compared two commercial supplement products, one made from cranberry juice extract and the other from a blend of whole cranberry. The influence of formulation and proanthocyanidin (PAC) solubility on in vitro and ex vivo P-fimbriated Escherichia coli bacterial anti-adhesion activity (AAA) was determined. Both supplement products as well as whole, frozen cranberries were chromatographically separated into crude polyphenolic, sugar and acid fractions. In vitro AAA testing of all fractions confirmed that only those containing soluble PACs elicited activity. The cranberry juice extract product had higher soluble PAC content than the whole cranberry blended product, which contained mainly insoluble PACs. The influence of soluble and insoluble PAC levels in each product on the urinary (ex vivo) AAA was determined following ingestion. The juice extract product was associated with significantly higher urinary AAA than that of the whole berry blended product when consumed once daily over the 1-week intervention period.

Abstract 6588: Omics integration provides insight into esophageal cancer inhibitory mechanisms of a cranberry extract

Our laboratory studies chemoprevention of esophageal adenocarcinoma (EAC) through utilization of the rat esophagogastroduodenal anastomosis (EGDA) surgical model of reflux-induced EAC. Specifically, we evaluated mechanisms by which cranberry proanthocyanidins (C-PAC) inhibit reflux-induced EAC by utilizing multi-omics integrative approaches employing multiple program platforms. Herein, we investigated whether pathway-based integration could be used to examine cross-talk between genes, metabolites and the microbial profiles. For this analysis, we utilized transcriptomic and untargeted metabolomic data from rat esophagi of animals that received water or C-PAC in the drinking water alone or combined with reflux inducing EGDA surgery. Additionally, we isolated DNA from fecal pellets and performed 16S rRNA sequencing to assess gut microbiome composition and functionality. Each omics dataset was analyzed for significant pathway enrichment and network generation using Metacore, DAVID and Metabolync. PICRUSt was utilized to predict microbiota functionality. Analysis of transcriptomic and metabolomic data suggest that EGDA upregulates inflammatory, NF-kB, DNA damage, cell cycle and immune function pathways as well as metabolic pathways related to eicosanoids, amino acids and primary and secondary bile acids, while C-PAC mitigates these alterations. Preliminary microbiome data analysis also suggests that bacteria related to inflammation, metabolite transport and DNA damage are increased in abundance in EGDA, with a decrease in abundance following C-PAC treatment. Analysis of omics datasets can provide insightful relationships into the cross-talk between different processes regulated by transcription, metabolism and the microbiome. Single dataset and integrative analysis showed similarities in altered pathways for vehicle and C-PAC treated animals in the context of reflux. Integration is limited by the infancy of multi-omics analysis programs, as well as the limited amount of research involving prediction of bacterial function and integration of microbiome data with other omics datasets. Further research and development of these omics programs is needed to determine accuracy of predicted results as well as continued investigation of identified pathways.

Citation Format: Katherine M. Weh, Connor L. Howard, Bridget A. Tripp, Jennifer L. Clarke, Amy B. Howell, Laura A. Kresty. Omics integration provides insight into esophageal cancer inhibitory mechanisms of a cranberry extract [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6588.

A randomized, double-blind, placebo-controlled pilot study to assess bacterial anti-adhesive activity in human urine following consumption of a cranberry supplement

Urinary tract infections (UTIs) are one of the common bacterial infections treated with antibiotics. The North American cranberry is recommended for prophylaxis in women with recurrent UTIs as a nutritional alternative. The ability of cranberry components and their metabolites to inhibit adhesion of uropathogenic Escherichia coli (E. coli) is an important mechanism by which cranberry mitigates UTIs. The objective of this study was to evaluate urinary anti-adhesion activity against type 1 and P-type uropathogenic E. coli after consumption of cranberry +health™ cranberry supplement (cranberry chew). In this randomized, double-blind, placebo-controlled, crossover design pilot trial (n = 20), subjects consumed two cranberry or placebo chews, one in the morning and one in the evening. Clean-catch urine samples collected at the baseline and post-intervention (0-3, 3-6, 6-9, 9-12, 12-24, 24-30, 30-36 h) were tested for anti-adhesion effects with a mannose-resistant human red blood cell hemagglutination assay specific for P-type E. coli, or a T24 cell line model for type 1 E. coli. Urinary anti-adhesion activity against P-type E. coli after consumption of the cranberry chew was significantly greater (p < 0.05) than that observed with placebo chew at all time points except 24-36 h. Ex vivo anti-adhesion effects on type 1 E. coli were greater (p < 0.05) after cranberry chew consumption than placebo chew at 3-6 and 6-9 h urine collections. In conclusion, consumption of cranberry +health™ cranberry supplement exhibited greater ex vivo urinary anti-adhesion activity compared to placebo, suggesting that it may have the potential to help promote urinary tract health.

Abstract 5077: Proteomic profiling reveals chemopreventive targets in esophageal adenocarcinoma

Esophageal adenocarcinoma (EAC) is characterized by rising incidence rates and high mortality due to late stage diagnosis and a lack of efficacious options for prevention and treatment. While reasons for the rapid increase in EAC are being unraveled, persistent, symptomatic reflux of gastric and duodenal contents, known as gastroesophageal reflux disease is considered the strongest risk factor. Our laboratory utilizes a rat surgical model of reflux-induced EAC to evaluate mechanisms by which cranberry proanthocyanidins (C-PAC) delivered in the drinking water inhibit reflux-induced EAC. Findings show that C-PAC (690ug/rat/day) inhibits EAC formation by 83% at 40 weeks of study and mechanisms of inhibition are under investigation. We utilized nano LC-MS/MS proteomic profiling to identify proteins that were dysregulated due to reflux-induced EAC and reversed with C-PAC treatment. Proteomic profiling revealed that C-PAC treatment restored 63 proteins dysregulated in the context of reflux. EIF3F, PSMD2 and ACTR2 were the top proteins up-regulated by reflux; whereas, top markers restored by C-PAC included GSTT2, OGN and PCMT1. Metacore integrated software showed top pathways up-regulated by reflux and down-regulated C-PAC included Translation_regulation of translation initiation (EIF-linked), Immune response and Regulation of telomere length. Conversely, C-PAC treatment upregulated the glutathione metabolism pathway which is consistent with GSTT2 restoration. Disease enrichment analysis revealed multiple gastrointestinal tract diseases linked to reflux, which C-PAC down regulated supporting that proteomic profiling may inform other potential disease targets for C-PAC. Finally, beyond the 63 reflux-driven proteins C-PAC reversed, we considered proteins, pathways and processes which could not be reversed by C-PAC (n=269). As an example, Process networks upregulated by reflux (not reversed by C-PAC) included Translation initiation (RPL-linked), Elongation, mRNA processing, G2-M and S-phase of the cell cycle. Thus, proteomics profiling may inform the development of complementary preventive combinations for improved cancer inhibitory efficacy, especially for a cancer like EAC, with high mutational burden. Western blot analysis of several markers in the rat esophagus including GSTT2 and COX2 support the data obtained through proteomic profiling. Future directions include interrogating specific pathways that are highly modulated by reflux-induced EAC and restored by C-PAC including DNA damage, repair and extracellular matrix and adhesion. Last, proteomic profiling has also allowed for identification of post-translational modifications which may provide insight into regulation of key dysregulated proteins.

Citation Format: Katherine M. Weh, Connor L. Howard, Amy B. Howell, Jennifer L. Clarke, Laura A. Kresty. Proteomic profiling reveals chemopreventive targets in esophageal adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 5077.

Antiviral effects of blueberry proanthocyanidins against Aichi virus

Blueberry polyphenols are known for their high antioxidant and antimicrobial potential. Aichi virus (AiV) is an emerging human enteric virus that causes gastroenteritis outbreaks worldwide. This study aimed to (1) determine the time- and dose-dependent effects of blueberry proanthocyanidins (B-PAC) against AiV over 24 h at 37 °C; (2) gain insights on their mode of action using pre- and post-treatment of host cells and Transmission Electron Microscopy; and (3) determine their anti-AiV effects in model foods and under simulated gastric conditions. AiV at ∼5 log PFU/ml was incubated with equal volumes of commercial blueberry juice (BJ, pH 2.8), neutralized BJ (pH 7.0), B-PAC (2, 4, and 10 mg/ml) prepared either in 10% ethanol, apple juice (AJ), 2% milk, simulated gastric fluid (SGF, pH 1.5) or simulated intestinal fluid (SIF, pH 7.5), and controls (malic acid (pH 3.0), phosphate buffered saline (pH 7.2), apple juice (pH 3.6) and 2% milk) over 24 h at 37 °C, followed by standard plaque assays. Each experiment was replicated thrice and data were statistically analyzed. Differences in AiV titers with 1 mg/ml B-PAC were 2.13 ± 0.06 log PFU/ml lower after 24 h and ≥3 log PFU/ml (undetectable levels) lower with 2 and 5 mg/ml B-PAC compared to AiV titers in PBS after 24 h and 3 h, respectively. BJ at 37 °C resulted in titer differences (lower titers compared to PBS) of 0.17 ± 0.06, 1.27 ± 0.01, and 1.73 ± 0.23 log PFU/ml after 1, 3, and 6 h and ≥3 log PFU/ml after 24 h. Pre- and post-treatment of host cells with 0.5 mg/ml B-PAC caused titer decreases of 0.62 ± 0.33 and 0.30 ± 0.06 log PFU/ml, respectively suggesting a moderate effect on viral-host cell binding. B-PAC at 2 mg/ml in AJ caused titer differences of ≥3 log PFU/ml after 0.5 h, while differences of 0.84 ± 0.03 log PFU/ml with 5 mg/ml B-PAC in milk, and ≥3 log PFU/ml with B-PAC at 5 mg/ml in SIF after 30 min were obtained. This study shows the ability of BJ and B-PAC to decrease AiV titers to potentially prevent AiV-related illness and outbreaks.

Cranberry-derived proanthocyanidins induce a differential transcriptomic response within Candida albicans urinary biofilms

Candida albicans is one of the most common causes of hospital-acquired urinary tract infections (UTIs). However, azoles are poorly active against biofilms, echinocandins do not achieve clinically useful urinary concentrations, and amphotericin B exhibits severe toxicities. Thus, novel strategies are needed to prevent Candida UTIs, which are often associated with urinary catheter biofilms. We previously demonstrated that cranberry-derived proanthocyanidins (PACs) prevent C. albicans biofilm formation in an in vitro urinary model. To elucidate functional pathways unique to urinary biofilm development and PAC inhibition, we investigated the transcriptome of C. albicans in artificial urine (AU), with and without PACs. C. albicans biofilm and planktonic cells were cultivated with or without PACs. Genome-wide expression analysis was performed by RNA sequencing. Differentially expressed genes were determined using DESeq2 software; pathway analysis was performed using Cytoscape. Approximately 2,341 of 6,444 total genes were significantly expressed in biofilm relative to planktonic cells. Functional pathway analysis revealed that genes involved in filamentation, adhesion, drug response and transport were up-regulated in urinary biofilms. Genes involved in carbon and nitrogen metabolism and nutrient response were down-regulated. In PAC-treated urinary biofilms compared to untreated control biofilms, 557 of 6,444 genes had significant changes in gene expression. Genes downregulated in PAC-treated biofilms were implicated in iron starvation and adhesion pathways. Although urinary biofilms share key features with biofilms formed in other environments, many genes are uniquely expressed in urinary biofilms. Cranberry-derived PACs interfere with the expression of iron acquisition and adhesion genes within urinary biofilms.

Abstract 279: Cranberry proanthocyanidins mitigate reflux-induced transporter dysregulation in esophageal adenocarcinoma

Esophageal adenocarcinoma (EAC) incidence rates have increased sharply (&gt;500%) throughout the Westernized world since the 1980s, despite the widespread use of endoscopy and anti-reflux medications. Reasons for the rapid increase in EAC are still being unraveled; however, persistent, symptomatic reflux of gastric and duodenal contents, known as gastroesophageal disease (GERD), is considered the strongest risk factor. Our laboratory utilizes the rat esophagogastroduodenal anastomosis (EGDA) surgical model of reflux-induced EAC to evaluate mechanisms by which cranberry proanthocyanidins (C-PAC) delivered in the drinking water inhibit reflux-induced EAC. Findings show that C-PAC inhibits EAC formation by 83% with concomitant restoration of the gut microbial profile and significant reduction of primary and secondary bile acid metabolites in the esophagus of animals with reflux-inducing surgery, but through unknown mechanisms. Herein, we investigated whether transporters, important in bile acid transport, buffering capacity, excretion, and even resistance to anticancer agents, were restored by C-PAC in the context of reflux. Additionally, we utilized a publicly available GEO dataset (GSE37203) to assess transporter expression levels in patients with metaplastic Barrett's esophagus (BE) versus those with high grade dysplasia (HGD) or EAC for translational relevance. Methods included esophageal RNA isolation, transcriptome sequencing using the Illumina HiSeq platform, followed by validation utilizing the PrimePCR Drug Transporter array plate and database mining. Results show significant changes in solute carriers (SLC), ATP-binding cassette (ABC) and aquaporin transporters in the rat reflux-induced model for EAC with C-PAC mitigating alterations. EGDA altered one or more members in 71% of the SLC families with frequent changes observed in SLC25, SLC4, SLC35, SLC2 and SLC6. C-PAC favorably impacted &gt;40% of the EGDA-induced SLC changes. A number of ABC transporters involved in glutathione transport and also implicated in drug resistance were altered by EGDA including Abcc1, Abcc3, Abcc4, Abcc5 and Abcg2 and C-PAC mitigated these changes. Aquaporins, Aqp3 and Aqp4, were significantly modulated in EGDA and restored with C-PAC. Significant differences in ABCC9, ABCC10, AQP6 and AQP9, in addition to several members of the SLC25, SLC4, SLC35, SLC2 and SLC6 families, were observed in patients with HGD/EAC compared to those with BE metaplasia. Therefore, altered expression of transporters following reflux-inducing surgery or GERD is likely a defensive mechanism by which cells attempt to adapt or protect from injurious bile acid exposure. Further research is warranted to investigate agents that restore normal transporter function, which may serve to concomitantly improve epithelial barrier function and mucosal integrity in the context of esophageal cancer progression.

Citation Format: Katherine M. Weh, Bridget A. Tripp, Jennifer L. Clarke, Amy B. Howell, Jules Lin, David G. Beer, Andrew C. Chang, Laura A. Kresty. Cranberry proanthocyanidins mitigate reflux-induced transporter dysregulation in esophageal adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 279.

Anthelmintic efficacy of cranberry vine extracts on ovine Haemonchus contortus

The discovery that plant secondary compounds, including proanthocyanidins (PAC), suppress gastrointestinal nematode (GIN) infection has provided promise for alternative methods of GIN control in small ruminants. This investigation is the first to examine the anthelmintic potential of cranberry vine (CV) against the GIN Haemonchus contortus. The purpose of this study was to explore the anti-parasitic activity of CV in the form of a specific organic proanthocyanidin extract (CV-PAC) and an aqueous extract (CV-AqE) containing PAC and other compounds. In vitro egg hatching, first (L1) and third (L3) stage larval and adult worm motility and L3 exsheathment were evaluated after a 24-h incubation with CV products. In addition, CV treated worms were observed via scanning electron microscopy, and a preliminary investigation of the efficacy of CV powder against an experimental infection of H. contortus was conducted. The in vivo effect on an experimental infection was determined by administering 21.1 g CV powder to lambs (n = 9 per group) for three consecutive days, and collecting fecal egg count data for four weeks post-treatment. The effect of CV-PAC on egg hatching, L3 motility and exsheathment was limited. However, a substantial effect was observed on motility of post-hatch L1 (EC₅₀ 0.3 mg PAC/mL) and adults (EC₅₀ 0.2 mg PAC/mL). The CV-AqE showed more effect on egg hatching (EC₅₀ 5.3 mg/mL containing 0.6 mg PAC/mL) as well as impacting motility of L1 (EC₅₀ 1.5 mg/mL with 0.2 mg PAC/mL) and adults (EC₅₀ 3.4 mg/mL with 0.4 mg PAC/mL), but like CV-PAC, did not substantially effect L3 motility or exsheathment. Scanning electron microscopy revealed an accumulation of aggregate on the cuticle around the buccal area of adult worms incubated in CV-AqE and CV-PAC. In the preliminary in vivo study, there was a significant effect of treatment over time (p = .04), although differences in individual weeks were not significant. In summary, both extracts inhibited motility of L1 and adult worms. The higher efficacy of CV-AqE than CV-PAC at levels that contained the same concentrations of PAC tested alone, suggest that other secondary compounds in the CV-AqE contributed to the observed effects on the parasites. This first study of the in vitro and in vivo effects of CV suggest that this readily available plant product may have utility in integrated control of H. contortus and support the need for additional testing to provide further information.

Abstract 5250: Cranberry proanthocyanidins reverse microbial dysbiosis and inhibit bile acid metabolism in association with esophageal cancer prevention

Our laboratory has been investigating the cancer inhibitory potential of cranberry proanthocyanidins (C-PAC) against esophageal adenocarcinoma (EAC), a cancer characterized by rapidly rising incident rates and poor survival (18% 5-year survival rate for all stages combined). Utilizing a panel of validated human esophageal cancer cell lines and OE19 xenograft bearing mice, our laboratory reported that C-PAC activates autophagic cell machinery leading to caspase-independent cancer cell death, yet linked to bile acid sensitivity. Reflux of bile and stomach acid into the lower esophagus is considered the major risk factor for progression to EAC. Building on our initial research, we next investigated mechanisms by which C-PAC inhibits reflux-induced EAC with a focus on gut microbiome alterations and modulation of bile acid metabolites. Bile acids undergo secondary metabolism in the intestinal tract, but have not been evaluated in this context. We utilized the rat surgical esophagogastroduodenal anastomosis (EGDA) model for reflux-induced EAC. EGDA+ and non-surgical Sprague Dawley rats were treated with water or C-PAC (650 µg/rat/day) for 25 or 40 weeks and assessed for cancer progression via extensive histopathological characterization. Additionally, at 40 weeks, fecal microbiome profiling was investigated and metabolic profiling conducted on esophageal, liver and fecal samples. Methods included 16s rRNA sequencing of rat fecal DNA, paired end sequencing on Illumina MiSeq and data analysis using Qiime and the R packages phyloseq, and edgeR to assess C-PAC-induced microbiome changes. For metabolite profiling homogenized esophagi, liver and fecal samples were extracted in methanol and characterized by Reverse Phase Ultra high Performance Liquid Chromatography-Tandem Mass Spectrometry RP/UPLC-MS/MS, followed by metabolite identification based on Metabolon’s library of authenticated standards. Study results support that C-PAC significantly inhibits the formation of EAC with concomitant restoration of the gut microbial profile, i.e., the bacterial profile shifted toward increased favorable Gram+ Firmicutes and away from inflammatory-linked Gram negative Bacteroidetes. In addition, C-PAC treatment significantly reduced primary and secondary bile acid metabolite levels in the esophagus of reflux/EGDA+ rats. Other metabolites significantly reduced by C-PAC included a number of pro-inflammatory Eicosanoids. In summary, these results support that (1) reflux-induced microbial impairment correlates with the stimulation of bile acid metabolism, and (2) C-PAC mitigates reflux-induced inflammation and injury in the esophagus in association with EAC inhibition. Future research with C-PAC in patients with gastroesophageal reflux disease should include assessments of bile acid metabolites and bacterial profiles as potential cancer-inhibitory mechanisms.

Citation Format: Katherine M. Weh, Nita H. Salzman, Amy B. Howell, Jennifer L. Clarke, Bridget A. Tripp, Laura A. Kresty. Cranberry proanthocyanidins reverse microbial dysbiosis and inhibit bile acid metabolism in association with esophageal cancer prevention [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5250. doi:10.1158/1538-7445.AM2017-5250

Reduction of Enteric Viruses by Blueberry Juice and Blueberry Proanthocyanidins

Blueberry and blueberry extracts are known for their health benefits and antimicrobial properties. Natural therapeutic or preventive options to decrease the incidences of foodborne viral illnesses are becoming popular and being researched. This study aimed to determine the antiviral effects of blueberry juice (BJ) and blueberry proanthocyanidins (BB-PAC, B-type PAC structurally different from A-type PAC found in cranberries) against the infectivity of hepatitis A virus (HAV) and human norovirus surrogates (feline calicivirus (FCV-F9) and murine norovirus (MNV-1)) at 37 °C over 24 h using standard plaque assays. Viruses at ~5 log PFU/ml were mixed with equal volumes of BJ (pH 2.8), neutralized BJ (pH 7.0), BB-PAC (1, 2, 4, and 10 mg/ml), malic acid (pH 3.0), or phosphate-buffered saline (pH 7.2) and incubated over 24 h at 37 °C. Each experiment was carried out in duplicate and replicated thrice. FCV-F9 titers were found to be reduced to undetectable levels with 1 and 2 mg/ml BB-PAC after 5 min, with 0.5 mg/ml BB-PAC after 1-h, and with BJ after 3-h. MNV-1 titers were reduced to undetectable levels after 3 h with 1, 2, and 5 mg/ml BB-PAC and after 6 h with BJ. HAV titers were reduced to undetectable levels after 30 min with 2 and 5 mg/ml BB-PAC, after 3 h with 1 mg/ml BB-PAC, and by ~2 log PFU/ml with BJ after 24-h. BB-PAC shows preventive potential against infection by the tested enteric viruses in a dose- and time-dependent manner, although further in vitro studies in model food systems and in vivo studies using animal models are warranted.

Blueberry proanthocyanidins against human norovirus surrogates in model foods and under simulated gastric conditions

Blueberry proanthocyanidins (B-PAC) are known to decrease titers of human norovirus surrogates in vitro. The application of B-PAC as therapeutic or preventive options against foodborne viral illness needs to be determined using model foods and simulated gastric conditions in vitro. The objective of this study was to evaluate the antiviral effect of B-PAC in model foods (apple juice (AJ) and 2% reduced fat milk) and simulated gastrointestinal fluids against cultivable human norovirus surrogates (feline calicivirus; FCV-F9 and murine norovirus; MNV-1) over 24 h at 37 °C. Equal amounts of each virus (5 log PFU/ml) was mixed with B-PAC (1, 2 and 5 mg/ml) prepared either in AJ, or 2% milk, or simulated gastric fluids and incubated over 24 h at 37 °C. Controls included phosphate buffered saline, malic acid (pH 7.2), AJ, 2% milk or simulated gastric and intestinal fluids incubated with virus over 24 h at 37 °C. The tested viruses were reduced to undetectable levels within 15 min with B-PAC (1, 2 and 5 mg/ml) in AJ (pH 3.6). However, antiviral activity of B-PAC was reduced in milk. FCV-F9 was reduced by 0.4 and 1.09 log PFU/ml with 2 and 5 mg/ml B-PAC in milk, respectively and MNV-1 titers were reduced by 0.81 log PFU/ml with 5 mg/ml B-PAC in milk after 24 h. B-PAC at 5 mg/ml in simulated intestinal fluid reduced titers of the tested viruses to undetectable levels within 30 min. Overall, these results show the potential of B-PAC as preventive and therapeutic options for foodborne viral illnesses.

Cranberry proanthocyanidins inhibit esophageal adenocarcinoma in vitro and in vivo through pleiotropic cell death induction and PI3K/AKT/mTOR inactivation

Cranberries are rich in bioactive constituents known to improve urinary tract health and more recent evidence supports cranberries possess cancer inhibitory properties. However, mechanisms of cancer inhibition by cranberries remain to be elucidated, particularly in vivo. Properties of a purified cranberry-derived proanthocyanidin extract (C-PAC) were investigated utilizing acid-sensitive and acid-resistant human esophageal adenocarcinoma (EAC) cell lines and esophageal tumor xenografts in athymic NU/NU mice. C-PAC induced caspase-independent cell death mainly via autophagy and low levels of apoptosis in acid-sensitive JHAD1 and OE33 cells, but resulted in cellular necrosis in acid-resistant OE19 cells. Similarly, C-PAC induced necrosis in JHAD1 cells pushed to acid-resistance via repeated exposures to an acidified bile cocktail. C-PAC associated cell death involved PI3K/AKT/mTOR inactivation, pro-apoptotic protein induction (BAX, BAK1, deamidated BCL-xL, Cytochrome C, PARP), modulation of MAPKs (P-P38/P-JNK) and G_2-M cell cycle arrest in vitro. Importantly, oral delivery of C-PAC significantly inhibited OE19 tumor xenograft growth via modulation of AKT/mTOR/MAPK signaling and induction of the autophagic form of LC3B supporting in vivo efficacy against EAC for the first time. C-PAC is a potent inducer of EAC cell death and is efficacious in vivo at non-toxic behaviorally achievable concentrations, holding promise for preventive or therapeutic interventions in cohorts at increased risk for EAC, a rapidly rising and extremely deadly malignancy.

A randomized, double-blind, placebo-controlled trial to assess the bacterial anti-adhesion effects of cranberry extract beverages

In this study, we examined the ex vivo urinary anti-adhesion activity of low-calorie cranberry extract beverages in both a pilot study (n = 10) and a randomized, double-blind, placebo controlled clinical trial (n = 59). In the pilot study, subjects consumed a cranberry extract beverage (CEB) or a cranberry extract and juice beverage (CEJB), compared to placebo. Both cranberry beverages utilized a standardized cranberry extract powder at a level equivalent to low-calorie cranberry juice cocktail (LCJC) on a PAC content basis. Clean-catch urine samples collected at baseline and post intervention were tested for anti-adhesion activity utilizing a mannose-resistant human red blood cell hemagglutination assay specific for P-fimbriated E. coli. Results from the pilot study indicated that ex vivo anti-adhesion activity for both cranberry treatments were higher (p < 0.05) than placebo. In the clinical trial, we compared CEJB to LCJC and a placebo beverage. Post-consumption urine from both cranberry treatment groups showed significantly higher (p < 0.05) anti-adhesion activity compared to placebo. There were no differences observed in anti-adhesion activity between CJEB and LCJC, indicating similar bioactivity. Therefore, acute beverage consumption of cranberry extract and/or juice provides ex vivo anti-adhesion activity, which may help to improve urinary tract health.

Cranberry proanthocyanidins modulate reactive oxygen species in Barrett's and esophageal adenocarcinoma cell lines

BACKGROUND

We recently reported that a cranberry proanthocyanidin rich extract (C-PAC) induces autophagic cell death in apoptotic resistant esophageal adenocarcinoma (EAC) cells and necrosis in autophagy resistant cells. EAC is characterized by high morbidity and mortality rates supporting development of improved preventive interventions.

OBJECTIVE

The current investigation sought to investigate the role of reactive oxygen species (ROS) in the context of C-PAC induced cell death.

METHODS

A panel of human esophageal cell lines of EAC or BE (Barrett's esophagus) origin were treated with C-PAC and assessed for ROS modulation using CellROX^® Green reagent and the Amplex Red assay to specifically measure hydrogen peroxide levels.

RESULTS

C-PAC significantly increased ROS levels in EAC cells, but significantly reduced ROS levels in CP-C BE cells. Increased hydrogen peroxide levels were also detected in C-PAC treated EAC cells and supernatant; however, hydrogen peroxide levels were significantly increased in medium alone, without cells, suggesting that C-PAC interferes or directly acts on the substrate. Hydrogen peroxide levels did not change in C-PAC treated CP-C BE cells.

CONCLUSION

These experiments provide additional mechanistic insight regarding C-PAC induced cancer cell death through modulation of ROS. Additional research is warranted to identify specific ROS species associated with C-PAC exposure.

Expression, modulation, and clinical correlates of the autophagy protein Beclin-1 in esophageal adenocarcinoma

Esophageal adenocarcinoma (EAC) is characterized by rapidly increasing incidence and mortality rates and poor survival. Efficacious preventive and treatment options are urgently needed. An increasing number of pharmacologic agents targeting cancer cell death via autophagy mechanisms are being evaluated in hopes of circumventing apoptotic and therapeutic resistance. We report for the first time, loss of Beclin-1, a key mediator of autophagy, was significantly linked to prognostic factors in EAC. Specifically, Beclin-1 expression loss occurred in 49.0% of EAC patients versus 4.8% of controls. There was a significant inverse correlation between loss of Beclin-1 with histologic grade and tumor stage supporting a tumor suppressive role for Beclin-1. Autophagy modulation linked to cell death was examined in EAC cell lines following treatment with a proanthocyanidin-rich cranberry extract, C-PAC, and the commonly used autophagy inducer, rapamycin. C-PAC induced Beclin-1-independent autophagy in EAC cells characterized by reduced phosphorylation at serine 15 and 93, and significant cell death induction. In contrast, rapamycin-induced autophagy resulted in concomitant, increases in total Beclin-1 levels as well as Beclin-1-phosphorylation in a cell line specific manner, leading to long-term cell survival. Furthermore, autophagic LC3-II was induced by C-PAC following siRNA suppression of Beclin-1 in EAC cells. Together these data support a prognostic role of Beclin-1 in EAC with evidence that Beclin-dependent autophagy induction is agent specific. Future studies are necessary to fully interrogate the role autophagy plays in the progression of normal tissue to EAC and how specific agents targeting autophagic mechanisms can be efficaciously applied for cancer prevention or treatment. © 2015 Wiley Periodicals, Inc.

Upper esophageal and pharyngeal cancers

The following, from the 12th OESO World Conference: Cancers of the Esophagus, includes commentaries on laryngopharyngeal reflux as a risk factor for laryngeal cancer; the role of pepsin in laryngopharyngeal neoplasia; natural fruit and vegetable compounds for the prevention and treatment of pharyngeal and esophageal cancers; and evaluation of cranberry constituents as inhibitors of esophageal adenocarcinoma utilizing in vitro assay and in vivo models.

Cranberry-derived proanthocyanidins prevent formation of Candida albicans biofilms in artificial urine through biofilm- and adherence-specific mechanisms

OBJECTIVES

Candida albicans is a common cause of nosocomial urinary tract infections (UTIs) and is responsible for increased morbidity and healthcare costs. Moreover, the US Centers for Medicare & Medicaid Services no longer reimburse for hospital-acquired catheter-associated UTIs. Thus, development of specific approaches for the prevention of Candida urinary infections is needed. Cranberry juice-derived proanthocyanidins (PACs) have efficacy in the prevention of bacterial UTIs, partially due to anti-adherence properties, but there are limited data on their use for the prevention and/or treatment of Candida UTIs. Therefore, we sought to systematically assess the in vitro effect of cranberry-derived PACs on C. albicans biofilm formation in artificial urine.

METHODS

C. albicans biofilms in artificial urine were coincubated with cranberry PACs at serially increasing concentrations and biofilm metabolic activity was assessed using the XTT assay in static microplate and silicone disc models.

RESULTS

Cranberry PAC concentrations of ≥16 mg/L significantly reduced biofilm formation in all C. albicans strains tested, with a paradoxical effect observed at high concentrations in two clinical isolates. Further, cranberry PACs were additive in combination with traditional antifungals. Cranberry PACs reduced C. albicans adherence to both polystyrene and silicone. Supplementation of the medium with iron reduced the efficacy of cranberry PACs against biofilms.

CONCLUSIONS

These findings indicate that cranberry PACs have excellent in vitro activity against C. albicans biofilm formation in artificial urine. We present preliminary evidence that cranberry PAC activity against C. albicans biofilm formation is due to anti-adherence properties and/or iron chelation.

Antibacterial effects of plant-derived extracts on methicillin-resistant Staphylococcus aureus

Natural chemicals have been reported to have antibacterial effects against a variety of bacteria. The present study evaluated the antibacterial effects of commercially available grape-seed extract (GSE), pomegranate polyphenols (PP), and lab-prepared cranberry proanthocyanidins (C-PAC) against two strains of methicillin-resistant Staphylococcus aureus (MRSA). GSE, PP, and C-PAC at concentrations of 2 mg/mL, 10 mg/mL, or controls were mixed with equal volumes of overnight cultures of MRSA at ~6 log₁₀ colony-forming units (CFU)/mL and incubated for 0, 1, 2, 8, and 24 h at 37°C. Treatments were neutralized/stopped using tryptic soy broth containing 3% beef extract. Serial dilutions of the treated MRSA strains and controls were spread-plated on trypticase soy agar and incubated for 24-48 h at 37°C and colonies were counted. Among the three tested agents, GSE at 1 and 5 mg/mL was found to be most effective against MRSA, resulting in a 2.9-4.0 log₁₀ CFU/mL reduction of both strains after 2 h at 37°C. PP at 1 and 5 mg/mL was found to cause 1.1-2.3 log₁₀ CFU/mL reduction, while C-PAC at 1 mg/mL caused <1 log₁₀ CFU/mL reduction of the two MRSA strains after 2 h at 37°C. All three extracts at the tested concentrations decreased the two MRSA strains to undetectable levels within 24 h, with the exception of 1 mg/mL PP for strain 33591. Scanning electron microscopy of MRSA after 2 h of treatment showed that GSE and PP caused bacterial cell wall alteration, with negligible effect observed by C-PAC treatment. However, the in vivo activity and clinical safety applications of GSE, PP, and C-PAC need to be evaluated before suggestion for use as a treatment/control measure.

Comparison of isolated cranberry (Vaccinium macrocarpon Ait.) proanthocyanidins to catechin and procyanidins A2 and B2 for use as standards in the 4-(dimethylamino)cinnamaldehyde assay

The 4-(dimethylamino)cinnamaldehyde (DMAC) assay is currently used to quantify proanthocyanidin (PAC) content in cranberry products. However, this method suffers from issues of accuracy and precision in the analysis and comparison of PAC levels across a broad range of cranberry products. Current use of procyanidin A2 as a standard leads to an underestimation of PACs content in certain cranberry products, especially those containing higher molecular weight PACs. To begin to address the issue of accuracy, a method for the production of a cranberry PAC standard, derived from an extraction of cranberry (c-PAC) press cake, was developed and evaluated. Use of the c-PAC standard to quantify PAC content in cranberry samples resulted in values that were 2.2 times higher than those determined by procyanidin A2. Increased accuracy is critical for estimating PAC content in relationship to research on authenticity, efficacy, and bioactivity, especially in designing clinical trials for determination of putative health benefits.

MicroRNA alterations in Barrett's esophagus, esophageal adenocarcinoma, and esophageal adenocarcinoma cell lines following cranberry extract treatment: Insights for chemoprevention

Background:

Aberrant expression of small noncoding endogenous RNA molecules known as microRNAs (miRNAs) is documented to occur in multiple cancer types including esophageal adencarcinoma (EAC) and its only known precursor, Barrett's esophagus (BE). Recent studies have linked dysregulation of specific miRNAs to histological grade, neoplastic progression and metastatic potential.

Materials and Methods:

Herein, we present a summary of previously reported dysregulated miRNAs in BE and EAC tissues as well as EAC cell lines and evaluate a cranberry proanthocyanidin rich extract's (C-PAC) ability to modulate miRNA expression patterns of three human EAC cell lines (JHEso-Ad-1, OE33 and OE19).

Results:

A review of 13 published studies revealed dysregulation of 87 miRNAs in BE and EAC tissues, whereas 52 miRNAs have been reported to be altered in BE or EAC cell lines, with 48% overlap with miRNA changes reported in tissues. We report for the first time C-PAC–induced modulation of five miRNAs in three EAC cell lines resulting in 26 validated gene targets and identification of key signaling pathways including p53, angiogenesis, T-cell activation and apoptosis. Additionally, mutiple cancer related networks were ideintified as modulated by C-PAC utilizing Kyoto Encyclopedia of Genes and Genomes (KEGG), Protein Analysis Through Evolutionary Relationships (PANTHER), and MetaCore analysis tools.

Conclusions:

Study results support the cancer inhibitory potential of C-PAC is in part attributable to C-PAC's ability to modify miRNA profiles within EAC cells. A number of C-PAC–modulated miRNAs have been been identified as dysregulated in BE and EAC. Further insights into miRNA dysregulation and modulation by select cancer preventive agents will support improved targeted interventions in high-risk cohorts.

Oral consumption of cranberry juice cocktail inhibits molecular-scale adhesion of clinical uropathogenic Escherichia coli

Cranberry juice cocktail (CJC) has been shown to inhibit the formation of biofilm by uropathogenic Escherichia coli. In order to investigate whether the anti-adhesive components could reach the urinary tract after oral consumption of CJC, a volunteer was given 16 oz of either water or CJC. Urine samples were collected at 0, 2, 4, 6, and 8 hours after consumption of a single dose. The ability of compounds in the urine to influence bacterial adhesion was tested for six clinical uropathogenic E. coli strains, including four P-fimbriated strains (B37, CFT073, BF1023, and J96) and two strains not expressing P-fimbriae but exhibiting mannose-resistant hemagglutination (B73 and B78). A non-fimbriated strain, HB101, was used as a control. Atomic force microscopy (AFM) was used to measure the adhesion force between a silicon nitride probe and bacteria treated with urine samples. Within 2 hours after CJC consumption, bacteria of the clinical strains treated with the corresponding urine sample demonstrated lower adhesion forces than those treated with urine collected before CJC consumption. The adhesion forces continued decreasing with time after CJC consumption over the 8-hour measurement period. The adhesion forces of bacteria after exposure to urine collected following water consumption did not change. HB101 showed low adhesion forces following both water and CJC consumption, and these did not change over time. The AFM adhesion force measurements were consistent with the results of a hemagglutination assay, confirming that oral consumption of CJC could act against adhesion of uropathogenic E. coli.

Cranberry proanthocyanidins mediate growth arrest of lung cancer cells through modulation of gene expression and rapid induction of apoptosis

Cranberries are rich in bioactive constituents purported to enhance immune function, improve urinary tract health, reduce cardiovascular disease and more recently, inhibit cancer in preclinical models. However, identification of the cranberry constituents with the strongest cancer inhibitory potential and the mechanism associated with cancer inhibition by cranberries remains to be elucidated. This study investigated the ability of a proanthocyanidin rich cranberry fraction (PAC) to alter gene expression, induce apoptosis and impact the cell cycle machinery of human NCI-H460 lung cancer cells. Lung cancer is the leading cause of cancer-related deaths in the United States and five year survival rates remain poor at 16%. Thus, assessing potential inhibitors of lung cancer-linked signaling pathways is an active area of investigation.

A-type cranberry proanthocyanidins inhibit the RANKL-dependent differentiation and function of human osteoclasts

This study investigated the effect of A-type cranberry proanthocyanidins (AC-PACs) on osteoclast formation and bone resorption activity. The differentiation of human pre-osteoclastic cells was assessed by tartrate-resistant acid phosphatase (TRAP) staining, while the secretion of interleukin-8 (IL-8) and matrix metalloproteinases (MMPs) was measured by ELISA. Bone resorption activity was investigated by using a human bone plate coupled with an immunoassay that detected the release of collagen helical peptides. AC-PACs up to 100 µg/mL were atoxic for osteoclastic cells. TRAP staining evidenced a dose-dependent inhibition of osteoclastogenesis. More specifically, AC-PACs at 50 µg/mL caused a 95% inhibition of RANKL-dependent osteoclast differentiation. This concentration of AC-PACs also significantly increased the secretion of IL-8 (6-fold) and inhibited the secretion of both MMP-2 and MMP-9. Lastly, AC-PACs (10, 25, 50 and 100 µg/ml) affected bone degradation mediated by mature osteoclasts by significantly decreasing the release of collagen helical peptides. This study suggests that AC-PACs can interfere with osteoclastic cell maturation and physiology as well as prevent bone resorption. These compounds may be considered as therapeutic agents for the prevention and treatment of periodontitis.

Abstract B67: In vitro and in vivo inhibitory effects of cranberry proanthocyanidins against esophageal adenocarcinoma

This study investigated the cancer inhibitory potential of a proanthocyanidin rich cranberry extract utilizing a panel of authenticated human esophageal adenocarcinoma cell lines (EAC), a nude mouse xenograft model, and the rat esophagogastrodoudenal anastomosis (EGDA) model of EAC. PACs effects on cell morphology, global gene expression, phase of cell cycle, and cell death induction via apoptosis, autophagy, and necrosis were evaluated. Methods included RapidDiff and MDC staining, Annexin/PI and BrdU staining with flow cytometric evaluation, transmission electron microscopy (TEM), protein evaluation utilizing standard Western blot techniques, and validation of global gene expression changes by real-time PCR. PAC treatment [50-100µg/ml] of EAC cancer cell lines resulted in significant increases in apoptosis, autophagy and necrosis. Differential cell death induction was noted based upon the cell lines resistance to a bile/acid cocktail mimicking acid exposure in humans as well as the status of the apoptotic and autophagic machinery of the select cell line. PACs cell death inducing capacity correlated with altered MAPKinase signaling as evidenced by activation of P-p38 and P-JNK and inhibition of P-ERK1/2. PAC treatment induced other proapoptotic markers including cleaved PARP, BAK1, BAX, and cytochrome C, but in a cell line dependent manner. Mild increases in Beclin-1 were noted following PAC treatment, as were significant increases in LC3II, a marker of autophagasome formation which occurs during autophagy induction. Results were confirmed by TEM and MDC staining. PAC induced cell cycle arrest at the G2/M transition, increased the percent of cells in G1, caused an S-phase delay and increased P21 levels in all three cell lines. PAC administration significantly inhibited the growth of OE19 xenografts via modulation of cell cycle and MAPK signaling pathways. Oral gavage of PAC [250µg/mouse] six times a week to nude mice resulted in a 67% decrease in OE19 tumor volume, increased cytochrome C protein levels and decreased levels of P-ERK1/2, cyclin A, PCNA, and CD31 in PAC treated tumors compared to vehicle treated tumors. Lastly, a four week pilot study was performed to evaluate the safety of daily administration of PAC in the rodent EGDA model. PAC appeared well tolerated given the average daily dose of 450µg/rat/day as evidenced by normal body weight and food consumption, serology profiles and histopathology of the major organs. Further long-term studies are planned to more fully access the chemopreventive potential of PAC against esophageal adenocarcinoma and premalignancy utilizing the clinically relevant rat EGDA surgical model.

Citation Information: Cancer Prev Res 2010;3(12 Suppl):B67.

Antiviral effects of cranberry juice and cranberry proanthocyanidins on foodborne viral surrogates--a time dependence study in vitro

Cranberry juice (CJ) and cranberry proanthocyanidins (PAC) are widely known for their antibacterial, antiviral, and pharmacological activities. The effect of CJ and cranberry PAC on the infectivity of foodborne viral surrogates, murine norovirus (MNV-1), feline calicivirus (FCV-F9), MS2 (ssRNA) bacteriophage, and ϕX-174 (ssDNA) bacteriophage after 0 min to 1h at room temperature was evaluated. Viruses at titers of ∼5log(10)PFU/ml were mixed with equal volumes of CJ at pH 2.6, CJ at pH 7.0, 0.30 mg/ml CJ PAC, 0.60mg/ml PAC, or water and incubated for 0, 10, 20, 30, 40, 50 min, and 1h at room temperature. Infectivity was determined using standard plaque assays. The viral reduction rates of the four tested viruses were found to vary considerably. Among the tested viruses, FCV-F9 titers were decreased the most by ∼5log(10)PFU/ml within 30 min. MS2 titers were decreased the least by only ∼1log(10)PFU/ml after 1h with CJ at pH 2.6 and 0.30 mg/ml PAC, and ∼0.5log(10)PFU/ml with CJ at pH 7.0 and 0.15 mg/ml PAC. MNV-1 and ϕ-X174 showed comparable titer reductions which was between that of FCV-F9 and MS2. In most cases, viral reduction within the first 10 min of treatment accounted for ≥50% of the total reduction. Transmission electron microscopy on FCV-F9 treated with CJ and PAC revealed structural changes. This study shows potential of using natural bioactive compounds for controlling foodborne viral diseases. Further studies are necessary to elucidate the mechanism of action of CJ components and to understand the differences in viral titer reduction profiles.

Dosage effect on uropathogenic Escherichia coli anti-adhesion activity in urine following consumption of cranberry powder standardized for proanthocyanidin content: a multicentric randomized double blind study

Background

Ingestion of cranberry (Vaccinium macrocarpon Ait.) has traditionally been utilized for prevention of urinary tract infections. The proanthocyanidins (PACs) in cranberry, in particular the A-type linkages have been implicated as important inhibitors of primarily P-fimbriated E. coli adhesion to uroepithelial cells. Additional experiments were required to investigate the persistence in urine samples over a broader time period, to determine the most effective dose per day and to determine if the urinary anti-adhesion effect following cranberry is detected within volunteers of different origins.

Methods

Two separate bioassays (a mannose-resistant hemagglutination assay and an original new human T24 epithelial cell-line assay) have assessed the ex-vivo urinary bacterial anti-adhesion activity on urines samples collected from 32 volunteers from Japan, Hungary, Spain and France in a randomized, double-blind versus placebo study. An in vivo Caenorhabditis elegans model was used to evaluate the influence of cranberry regimen on the virulence of E. coli strain.

Results

The results indicated a significant bacterial anti-adhesion activity in urine samples collected from volunteers that consumed cranberry powder compared to placebo (p < 0.001). This inhibition was clearly dose-dependent, prolonged (until 24 h with 72 mg of PAC) and increasing with the amount of PAC equivalents consumed in each cranberry powder regimen. An in vivo Caenorhabditis elegans model showed that cranberry acted against bacterial virulence: E. coli strain presented a reduced ability to kill worms after a growth in urines samples of patients who took cranberry capsules. This effect is particularly important with the regimen of 72 mg of PAC.

Conclusions

Administration of PAC-standardized cranberry powder at dosages containing 72 mg of PAC per day may offer some protection against bacterial adhesion and virulence in the urinary tract. This effect may offer a nyctohemeral protection.

Cranberry proanthocyanidins inhibit MMP production and activity

Matrix metalloproteinases (MMPs) produced by resident and inflammatory cells in response to periodontopathogens play a major role in periodontal tissue destruction. Our aim was to investigate the effects of A-type cranberry proanthocyanidins (AC-PACs) on: (i) the production of various MMPs by human monocyte-derived macrophages stimulated with Aggregatibacter actinomycetemcomitans lipopolysaccharide (LPS), and (ii) the catalytic activity of recombinant MMP-1 and MMP-9. The effects of AC-PACs on the expression of 5 protein kinases and the activity of nuclear factor-kappa B (NF-kappaB) p65 in macrophages stimulated with LPS were also monitored. Our results indicated that AC-PACs inhibited the production of MMPs in a concentration-dependent manner. Furthermore, the catalytic activity of MMP-1 and MMP-9 was also inhibited. The inhibition of MMP production was associated with reduced phosphorylation of key intracellular kinases and the inhibition of NF-kappaB p65 activity. AC-PACs thus show potential for the development of novel host-modulating strategies to inhibit MMP-mediated tissue destruction during periodontitis.

Cranberry proanthocyanidins induce apoptosis and inhibit acid-induced proliferation of human esophageal adenocarcinoma cells

The occurrence of esophageal adenocarcinoma and its only recognized precursor lesion, Barrett's esophagus, has rapidly increased during the past three decades. The precise reason for the rise remains to be elucidated, but increasing rates have been linked to multiple nutritional factors. Plant-based diets have generally been associated with a reduction of risk for esophageal adenocarcinoma and those of animal origin with risk escalation. Moreover, a number of recent in vitro and limited in vivo investigations have reported that cranberry extracts affect multiple cancer-associated processes in breast, colon, prostate, and other cancer cell lines of epithelial origin. Thus, this study sought to investigate the chemopreventive potential of a cranberry proanthocyanidin rich extract (PAC) in SEG-1 human esophageal adenocarcinoma (EAC) cells. PAC pretreatment significantly inhibited the viability and proliferation of EAC cells in a time- and dose-dependent manner. Moreover, PAC (50 microg/mL) significantly inhibited acid-induced cell proliferation of SEG-1 cells. PAC treatment induced cell cycle arrest at the G1 checkpoint and significantly reduced the percentage of SEG-1 cells in S-phase following 24 and 48 h of exposure. PAC treatment also resulted in significant induction of apoptosis. Thus, PAC modulates cell cycle regulation, aberrant proliferation, and apoptosis, all key biological processes altered during progression to esophageal adenocarcinoma. These findings support that further mechanistic studies are warranted to more fully elucidate the inhibitory potential of PAC against esophageal cancer.

Bioactive compounds in cranberries and their role in prevention of urinary tract infections

Cranberry (Vaccinium macrocarpon Ait.) ingestion has long been associated with prevention of urinary tract infections. The beneficial mechanism was historically thought to be due to the fruit acids causing a bacteriostatic effect in the urine. However, recently, a group of proanthocyanidins (PACs) with A-type linkages were isolated from cranberry which exhibit bacterial antiadhesion activity against both antibiotic susceptible and resistant strains of uropathogenic P-fimbriated Escherichia coli bacteria. The link between cranberry ingestion and maintenance of urinary tract health as well as the structural diversity, pharmacokinetics, quantification, and bacterial antiadhesion bioactivity of the A-linked cranberry PACs are reviewed.

Consumption of Sweetened Dried Cranberries Versus Unsweetened Raisins for Inhibition of Uropathogenic Escherichia coli Adhesion in Human Urine: A Pilot Study

OBJECTIVES

The aim of this study was to determine whether consumption of sweetened dried cranberries elicits urinary anti-adherence properties against Escherichia coli as previously demonstrated with cranberry juice and/or sweetened cranberry juice cocktail, compared to unsweetened raisins.

DESIGN

Uropathogenic E. coli isolates were obtained from five women with culture-confirmed urinary tract infections (UTIs). Four urine samples were collected from each subject. The first urine sample was collected before any study intervention. The second urine sample was collected 2-5 hours after consumption of one box (42.5 g) of raisins. The third urine sample was collected 5-7 days later. The final urine sample was collected 2-5 hours after consumption of approximately 42.5 g of dried cranberries.

MATERIALS AND METHODS

E. coli isolates were incubated separately in each of the four urine samples collected from the five subjects. Bacteria were harvested from the urine and tested for the ability to prevent adhesion of P-fimbriated E. coli bacteria using a mannose-resistant hemagglutination assay with human red blood cells (A1, Rh+).

RESULTS

Of the urine samples collected after dried cranberry consumption, one demonstrated 50% antiadherence activity, two demonstrated 25% activity, and two did not show any increased activity. None of the control urine samples and none of the postraisin consumption samples demonstrated any inhibitory activity.

CONCLUSIONS

Data from this pilot study on only five subjects suggest that consumption of a single serving of sweetened dried cranberries may elicit bacterial antiadhesion activity in human urine, whereas consumption of a single serving of raisins does not. Further studies are needed to verify the antiadhesion effect of sweetened dried cranberries. In addition, dose-response and pharmacokinetics of the active compounds in the dried cranberries need to be determined. If clinical research is positive, dried cranberries could potentially be a viable alternative to cranberry juice consumption for prevention of UTIs.

A-type cranberry proanthocyanidins and uropathogenic bacterial anti-adhesion activity

Clinical, epidemiological and mechanistic studies support the role of cranberry (Vaccinium macrocarpon Ait.) in maintaining urinary tract health. Cranberry proanthocyanidins contain A-type linkages and have been associated with preventing adhesion of P-fimbriated uropathogenic Escherichia coli to uroepithelial cells. It is not known if the presence of the A-type linkage is a prerequisite for anti-adhesion activity. Other commercial sources of proanthocyanidins with all B-type linkages have not previously been screened for this activity. The goals of this study were to compare the in vitro anti-adhesion activity of A-linked proanthocyanidins from cranberry juice cocktail with the anti-adhesion activities of B-linked proanthocyanidins from commercial grape and apple juices, green tea and dark chocolate, and determine if anti-adhesion activity is detectable in human urine following consumption of single servings of each commercial food product. Structural heterogeneity and presence of the A-type linkage in cranberry proanthocyanidins was confirmed utilizing MALDI-TOF/MS and DI/ESI MS, as was the presence of all B-type linkages in the proanthocyanidins from the other commercial products. The isolated A-type proanthocyanidins from cranberry juice cocktail elicited in vitro anti-adhesion activity at 60 microg/ml, the B-type proanthocyanidins from grape exhibited minor activity at 1200 microg/ml, while other B-type proanthocyanidins were not active. Anti-adhesion activity in human urine was detected following cranberry juice cocktail consumption, but not after consumption of the non-cranberry food products. Results suggest that presence of the A-type linkage in cranberry proanthocyanidins may enhance both in vitro and urinary bacterial anti-adhesion activities and aid in maintaining urinary tract health.

Effective separation of potent antiproliferation and antiadhesion components from wild blueberry (Vaccinium angustifolium Ait.) fruits

Extracts from wild blueberry (Vaccinium angustifolium Ait.) were separated into proanthocyanidin-rich fractions using liquid vacuum and open column chromatography on Toyopearl and Sephadex LH-20, respectively. Fractions were characterized using analytical tools including mass spectrometry and NMR spectroscopy; fraction composition was correlated with bioactivity using antiproliferation and antiadhesion in vitro assays. There was a significant positive correlation between proanthocyanidin content of different fractions and biological activity in both the antiproliferation and antiadhesion assays. Two fractions containing primarily 4-->8-linked oligomeric proanthocyanidins with average degrees of polymerization (DPn) of 3.25 and 5.65 inhibited adhesion of Escherichia coli responsible for urinary tract infections. Only the fraction with a DPn of 5.65 had significant antiproliferation activity against human prostate and mouse liver cancer cell lines. These findings suggest both antiadhesion and antiproliferation activity are associated with high molecular weight proanthocyanidin oligomers found in wild blueberry fruits.

Cranberry proanthocyanidins and the maintenance of urinary tract health

One of the major health benefits attributed to the ingestion of cranberry juice is the maintenance of urinary tract health. Traditionally, the juice was thought to cause acidification of the urine resulting in a bacteriostatic effect. However, recent research has demonstrated that a bacterial antiadhesion mechanism is responsible. Proanthocyanidins with unique molecular structures have been isolated from cranberry fruit that exhibit potent bacterial antiadhesion activity. Little is known about the bioavailability and structure-activity relationships of cranberry proanthocyanidins. Data on how certain structural features of the molecules can influence bioactivity and bioavailability are reviewed.