appear most suited to stable small molecule chemicals as antibodies or recombinant proteins had no effect, most likely due to poor bioavailability in the eye or degradation. Future Perspectives In summary, we provide evidence that a broad-spectrum PI3K inhibitor can attenuate ocular angiogenesis without perturbing visual function. Thus, there can be cautious optimism about the potential clinical use of PI3K inhibitors to treat unwanted ocular neovascularisation. This could involve administration of an isoform-specific inhibitor or a vasculature-targeted prodrug, either as monotherapies or part of combination angiostatic therapies. Supporting Information Figure S1 Intraocular Injection of LY294002 in zebrafish larvae. A) ,5 dechorionated zebrafish larvae (48 hpf in the figure) are immobilized in CyGEL at RT and oriented with left eye facing upwards. Dechorionation is extremely important as non-dechor- ionated larvae collapse in contact with CyGEL. B) Intraocular injection (0.1–0.2 ml/eye) is performed with a heat pulled glass capillary. C) After intraocular injection the Petri dish is placed on a chilled ice pad to melt CyGEL and larvae are transferred gently but immediately to a plate with RT embryo medium for recovery. Found at: doi:10.1371/journal.pone.0007867.s001 (4.36 MB TIF) Figure S2 Regenerative angiogenesis in zebrafish dorsal or anal fins is inhibited by LY294002. The dorsal (A, C and E) or anal fins (B, References 1. Frank RN (2004) Diabetic retinopathy. N Engl J Med 350(1): 48–58. 2. Jager RD, Mieler WF, Miller JW (2008) Age-related macular degeneration. N Engl J Med 358(24): 2606–17. 3. Pierce EA, Foley ED, Smith LE (1996) Regulation of vascular endothelial growth factor by oxygen in a model of retinopathy of prematurity. Arch Ophthalmol 114(10): 1219–28. 4. Hernandez C, Simo R (2007) Strategies for blocking angiogenesis in diabetic retinopathy: from basic science to clinical practice. 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Ihle NT, Powis G (2009) Take your PIK: phosphatidylinositol 3-kinase inhibitors race through the clinic and toward cancer therapy. Mol Cancer Ther 8(1): 1–9. PLoS ONE | www.plosone.org 9 November 2009 | Volume 4 | Issue 11 | e7867