Tumor angiogenesis is caused by single melanoma cells in a reactive oxygen species and NF-κB dependent manner

Abstract

SummaryMelanomas have a high angiogenic potential, but respond poorly to medical treatment and metastasize very early. To understand the early events in tumor angiogenesis, animal models with high tumor resolution and blood vessel resolution are required, which provide the opportunity to test the ability of small molecule inhibitors to modulate the angiogenic tumor program. We have established a transgenic melanoma angiogenesis model in the small laboratory fish species Japanese medaka. Here, pigment cells are transformed by an oncogenic receptor tyrosine kinase in fish expressing GFP throughout their vasculature. We show that angiogenesis occurs in a reactive oxygen species (ROS)-and NF-kB-dependent, but hypoxia-independent manner. Intriguingly, we observed that blood vessel sprouting is induced even by single transformed pigment cells. The oncogenic receptor as well as human melanoma cells harboring other oncogenes caused the production of pro-angiogenic factors, most prominently angiogenin, through NF-kB signaling. Inhibiting NF-kB prevented tumor angiogenesis and led to the regression of existing tumor blood vessels.In conclusion, our high-resolution medaka melanoma model discloses that ROS and NF-kB signaling from single tumor cells causes hypoxia-independent angiogenesis, thus, demonstrating that the intrinsic malignant tumor cell features are sufficient to initiate and maintain a pro-angiogenic signaling threshold.

Reciprocal analyses in zebrafish and medaka reveal that harnessing the immune response promotes cardiac regeneration

“…We used the zebrafish AB strain (RRID:ZIRC_ZL1) as well as the following transgenic lines Tg(mpeg1:EGFP) gl22 (Ellett et al, 2011), Tg(mpeg1.4:mCherry-F) ump2 (Bernut et al, 2014), and TgBAC(mpx:GFP) i114 (Renshaw et al, 2006). We used the medaka WT Cab strain as well as the following transgenic lines fli::GFP;gata1::GFP (Schaafhausen et al, 2013), fli1-GFP (Moriyama et al, 2010; Ito et al, 2014), and Cab-Tg(zfmlc2 5.1 k:DsRed2-nuc) TG1026 (Taneda et al, 2010). The two medaka fli alleles were generated independently using the same plasmid, and we did not observe any difference in expression between them.…”

The role of chemical elements in melanoma

“…The antioxidant pattern has been found altered in experimental melanoma (Lazescu, 2013) and in simvastatin-treated melanoma cells undergoing a p53/p21 -mediated senescence (Guterres, 2013); the ROS pool can be produced by NADPH oxidase enzymes (NOX family), representing a promising target for melanoma treatment (LiuSmith, 2014). ROS have been found to mediate the pro-angiogenic potential of melanoma cells (Schaafhausen, 2013;Vartanian, 2007); ROS mediate the in vitro apoptosis and growth inhibition of A375 human melanoma cells and other melanoma cells, induced by several different agents (Huang, 2014;Huang, 2012;Chakraborty, 2013;Ghosh, 2013;Mayola, 2011;Zhang, 2010;Morrison, 2010;Chou, 2009;Wang, 2008;Verhaegen, 2006) and of B16F10 mouse melanoma cells migration properties (Im, 2012). Blocking ROS production has been shown to reduce the anti-5 melanoma activity of Cucurbitacin B (Zhang 2011) while decreasing ROS promotes melanoma growth (Huang 2010).…”

Genetic Developmental Timing Revealed by Inter-Species Transplantations in Fish

“…The following medaka lines were used in this study: Cab strain as a wild type, Heino (Albino medaka) (reference), Wimbledon DsTrap#6 [7], Rx2::H2B-mRFP [13], zFli1::EGFP [53], Gaudi RSG (contains the integration reporter crya:ECFP that drives ECFP expression in the lens), Gaudi LoxPOUT [12], Atoh7::EGFP [15], Atoh7::lynTdTomato [54].…”