Black raspberries inhibit N-nitrosomethylbenzylamine (NMBA)-induced angiogenesis in rat esophagus parallel to the suppression of COX-2 and iNOS. Carcinogenesis 2006 Nov;27(11):2301-7
Date
06/17/2006Pubmed ID
16777990DOI
10.1093/carcin/bgl109Scopus ID
2-s2.0-33750444284 (requires institutional sign-in at Scopus site) 74 CitationsAbstract
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.
Author List
Chen T, Rose ME, Hwang H, Nines RG, Stoner GDMESH terms used to index this publication - Major topics in bold
AnimalsCarcinogens
Cyclooxygenase 2
Dimethylnitrosamine
Esophageal Neoplasms
Female
Fruit
Gene Expression Regulation, Enzymologic
Gene Expression Regulation, Neoplastic
Microcirculation
Neovascularization, Pathologic
Nitric Oxide Synthase Type II
Plant Extracts
Rats
Rats, Inbred F344