The impact of tumor nitric oxide production on VEGFA expression and tumor growth in a zebrafish rat glioma xenograft model

• Published in: PloS one 2015-03, Vol.10 (3), p.e0120435-e0120435
• Main Authors: Yousfi, Nadhir, Pruvot, Benoist, Lopez, Tatiana, Magadoux, Lea, Franche, Nathalie, Pichon, Laurent, Salvadori, Françoise, Solary, Eric, Garrido, Carmen, Laurens, Véronique, Chluba, Johanna
• Format: Article
• Language: English
• Subjects: Adaptive immunology; Analysis of Variance; Angiogenesis; Animals; Benzoates; Benzoates - pharmacology; Blood vessels; Brain tumors; Cancer; Cyclin D1; Cyclin D1 - metabolism; Danio rerio; Embryos; Flow Cytometry; Gene expression; Gene Expression Regulation, Neoplastic; Gene Expression Regulation, Neoplastic - physiology; Glioma; Glioma - metabolism; Glioma cells; Gliomas; Heterografts; Histological Techniques; Imidazoles; Imidazoles - pharmacology; Immunology; Innate immunity; Kinases; Laboratory animals; Life Sciences; mRNA; Nitric Oxide; Nitric Oxide - metabolism; Production processes; Rats; Real-Time Polymerase Chain Reaction; Reverse Transcriptase Polymerase Chain Reaction; Rodents; Studies; Tumor cells; Tumors; Vascular Endothelial Growth Factor A; Vascular Endothelial Growth Factor A - metabolism; Xenografts; Zebrafish
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0120435

To investigate the effect of nitric oxide on tumor development, we established a rat tumor xenograft model in zebrafish embryos. The injected tumor cells formed masses in which nitric oxide production could be detected by the use of the cell-permeant DAF-FM-DA (diaminofluorophore 4-amino-5-methylamino-2'-7'-difluorofluorescein diacetate) and DAR-4M-AM (diaminorhodamine-4M). This method revealed that nitric oxide production could be co-localized with the tumor xenograft in 46% of the embryos. In 85% of these embryos, tumors were vascularized and blood vessels were observed on day 4 post injection. Furthermore, we demonstrated by qRT-PCR that the transplanted glioma cells highly expressed Nos2, Vegfa and Cyclin D1 mRNA. In the xenografted embryos we also found increased zebrafish vegfa expression. Glioma and zebrafish derived Vegfa and tumor Cyclin D1 expression could be down regulated by the nitric oxide scavenger 2-(4-Carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide or CPTIO. We conclude that even if there is a heterogeneous nitric oxide production by the xenografted glioma cells that impacts Vegfa and Cyclin D1 expression levels, our results suggest that reduction of nitric oxide levels by nitric oxide scavenging could be an efficient approach to treat glioma.