Our laboratory has used a rodent model of human esophageal squamous cell carcinoma to identify putative chemopreventive agents for this disease and to determine their mechanisms of action. In the present study, we treated F344 rats with the esophageal carcinogen, N-nitrosomethylbenzylamine (NMBA), thrice per week for 5 weeks. Beginning 1 week later, they were fed a synthetic diet containing 5% black raspberries (BRB) for the duration of the bioassay (25 weeks). Rats were sacrificed at weeks 9, 15, and 25. Esophageal tissues were collected, and tumor data were recorded. The expression and enzymatic activities of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) as well as the expression of c-Jun in the esophagi, were evaluated to investigate the mechanism(s) by which black raspberries modulate tumorigenesis. At week 25, BRB inhibited tumor multiplicity, the standard end point in this tumor model, from 3.78 F 0.41 tumors per rat in NMBAtreated animals to 2.23 F 0.21 tumors per rat in animals treated with NMBA plus BRB (P < 0.005). BRB reduced mRNA and protein expression levels of COX-2, iNOS, and c-Jun as well as the level of prostaglandin E 2 in preneoplastic lesions of the esophagus at week 25. The berries inhibited mRNA expression of iNOS and c-Jun, but not COX-2, in papillomatous lesions of the esophagus. Prostaglandin E 2 and total nitrite levels were also decreased by BRB in papillomas. These results suggest a novel tumor suppressive role of BRB through inhibition of COX-2, iNOS, and c-Jun.

Angiogenesis, the formation of new blood vessels, is critical to tumor growth and metastasis. Vascular endothelial growth factor (VEGF), an important angiogenic activator, is essential for angiogenesis. Our laboratory has used a rodent model of human esophageal squamous cell carcinoma (ESCC) to identify putative chemopreventive agents for this disease and determine their mechanisms of action. We reported that dietary black raspberry powder (BRB) inhibits N-nitrosomethylbenzylamine (NMBA)-induced tumor development in the rat esophagus by inhibiting the formation of DNA adducts and reducing the proliferation rate of preneoplastic cells. On a molecular level, BRB downregulates the expression of c-Jun, cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS). In this study we analyzed the effect of BRB on angiogenesis. VEGF expression was determined by real-time RT-PCR and immunohistochemical analysis of microvessel density (MVD). BRB significantly suppressed VEGF-C expression from a 2.38 (+/- 0.34)-fold increase in animals treated with NMBA alone to a 1.08 (+/- 0.22)-fold increase in animals treated with NMBA plus BRB (P < 0.005). The MVD of esophagus was decreased from 53.7 +/- 5.6 vessels/cm in animals treated with NMBA alone to 22.6 +/- 2.6 vessels/cm in animals treated with NMBA plus BRB (P < 0.0001). Our data also suggest that downregulation of VEGF is correlated with suppression of COX-2 (r2 = 0.86, P < 0.001) and iNOS (r2 = 0.81, P < 0.005). As high vascularity is a risk factor for metastasis and tumor recurrence, BRB may have cancer therapeutic effects in human esophageal cancer.

Epidemiological studies suggest that the frequent intake of non-steroidal anti-inflammatory drugs (NSAIDs) is associated with a decreased risk of developing esophageal squamous cell carcinoma (SCC). This decrease is thought to correlate with the inhibition of cyclooxygenase (COX) activity. The production of prostaglandin E2 (PGE2), a major metabolite of COX, is increased in numerous human cancers including esophageal SCC, therefore, inhibition of COX activity and subsequent suppression of the formation of PGE2 may be chemopreventive in the esophagus. The objective of the present study was to determine whether L-748706 (L-706), a novel selective COX-2 inhibitor, would prevent N-nitrosomethylbenzylamine (NMBA)-induced esophageal tumor progression in the Fischer 344 (F344) rat. In rats pretreated with a low-dose of NMBA (0.25 mg/kg body weight), L-706 at 100 p.p.m. in the diet significantly reduced tumor multiplicity but not tumor incidence. At 150 p.p.m. in the diet, L-706 alone and in combination with 200 p.p.m. piroxicam produced significant reductions in both tumor incidence and multiplicity. Inhibition of tumor development in low-dose NMBA-treated rats was associated with reductions in esophageal cell proliferation rates and PGE2 levels in preneoplastic tissues. In contrast, in rats treated with a higher dose of NMBA (0.5 mg/kg body weight), neither L-706 alone nor in combination with piroxicam reduced esophageal tumor incidence or multiplicity in spite of the fact that they reduced esophageal PGE2 levels in preneoplastic tissues and in papillomas. Cell proliferation rates were reduced only in animals treated with L-706 + piroxicam. Our data suggest that the chemopreventive treatments were effective in inhibiting tumor development in NMBA-treated animals only when they reduced PGE2 levels in preneoplastic esophageal tissues approximately to those levels found in normal esophagus.

As oral bacteria grow and persist within biofilms attached to the tooth’s surface, they interact with other species to form synergistic or antagonistic exchanges that govern homeostasis for the overall population. One example are the interactions between the cariogenic species Streptococcus mutans and oral commensal streptococci. Previously, we showed that the cell–cell signaling pathways of S. mutans were inhibited during coculture with other oral streptococci species, leading us to posit that the S. mutans transcriptome and behaviors are broadly altered during growth with these species. To test this hypothesis, we performed whole transcriptome sequencing (RNA-seq) on cocultures of S. mutans with either Streptococcus gordonii, Streptococcus sanguinis, or Streptococcus oralis and a quadculture containing all 4 species in comparison to S. mutans grown alone. Our results reveal that in addition to species-dependent changes to the S. mutans transcriptome, a conserved response to oral streptococci in general can be observed. We monitored the behavior of S. mutans by both microscopy imaging of biofilms and in a bacteriocin overlay assay and verified that S. mutans acts similarly with each of these species but noted divergences in phenotypes when cocultured with another cariogenic Streptococcus ( Streptococcus sobrinus) or with oral nonstreptococci species. RNA-seq with oral nonstreptococci showed lack of a consistent gene expression profile and overlap of differentially expressed genes found with commensal streptococci. Finally, we investigated the role of upregulated S. mutans genes within our data sets to determine if they provided a fitness benefit during interspecies interactions. Eleven total genes were studied, and we found that a majority impacted the fitness of S. mutans in various assays, highlighted by increased biomass of commensal streptococci in mixed-species biofilms. These results confirm a common, species-independent modification of S. mutans behaviors with oral commensal streptococci that emphasizes the need to further evaluate oral bacteria within multispecies settings.

Childhood obesity remains a serious public health threat. There is an urgent need for innovative, effective, and sustainable interventions for childhood obesity that are multisector, integrated, and pragmatic. Using the 2007 Expert Committee on the Assessment, Prevention, and Treatment of Child and Adolescent Overweight and Obesity as a guide, a tertiary care obesity program at a children's hospital established the Primary Care Obesity Network (PCON). This article describes the structure, implementation, resources, and outcome measures of the PCON, a network of primary care practices and a tertiary care obesity center established to prevent and treat childhood obesity in Central Ohio. This program offers an opportunity to assess how and whether the expert committee guidelines can be translated into practice. As Accountable Care Organizations strive to provide services through the lens of improving population health, the PCON can serve as an example for addressing childhood obesity.