VEGFA and urinary bladder cancer: In this study, using lentivirus-mediated KLF5 knockdown strategy, we found that KLF5 not only revealed its pro-proliferative role in bladder cancer cell lines, but also regulated the interaction between bladder cancer cells and vascular endothelial cells in vitro and promoted bladder cancer angiogenesis in vivo through directly regulating vascular endothelial growth factor A (VEGFA) transcription.