VEGFB and carcinoma: Interestingly, the pro-angiogenic ligand-receptor interactions of FLT1(VEGFR1)-PGF, FLT1(VEGFR1)-VEGFB, ACKR1-CXCL8, and FLT1(VEGFR1)-VEGFA between endothelial cells and urothelial-derived carcinoma cells were enriched and displayed higher expression levels compared to other interactions in NMIBC (Figure 1A); however, only FLT1(VEGFR1)-PGF and FLT1(VEGFR1)-VEGFA exhibited higher expression in MIBC (Figure 1B).