VEGFA and neoplasm: On the other hand, the VEGF concentration was significantly higher in cultures of spheroids with a larger proportion of tumor cells (1:1:1 vs. 1:3:10, with or without VEGF supplementation, Figure 5E), even in the absence of fibroblasts (monotypic tumor spheroids and tumor–EC double heterotypic spheroids, Figure 5E); nonetheless, ECs were not maintained in these double cocultures (Supplementary Figure 7A).