Gene expression analysis for angiogenic and angiostatic factors at endpoint (Supplementary Fig. 3a) revealed, in addition to changes in fibroblast growth factor-2 and angiopoietin-2 expression, a marked decrease in the expression of the angiostatic soluble form of VEGF receptor 1 (sVEGFR1) in tumours from HIF-1α KO mice, whereas VEGF expression was similar across genotypes (Supplementary Fig. 3a). Here, VEGFA is linked to neoplasm.