Expression changes in KLF5 in human prostate cancer cell lines modulate the angiogenic activities of HuVECs. Tube formation assay (A, B) and transwell assay (C, D) of human umbilical vein endothelial cells (HuVECs) with conditioned media (CM) from PC-3 and DU 145 cells with KLF5 knockdown (A) and ectopic expression (B) mediated by lentiviral infection. For tube formation assay, tube length and node number from ten fields were measured with ImageJ software, and each unit is 100 pixels. For transwell assay, HuVECs were seeded in the upper chamber with serum-free medium. Conditioned media was added to the lower wells, and cells migrating to the bottom side of the upper chamber were stained with crystal violet and counted from 20 fields at 4× with ImageJ software. shK1 and shK2 indicate two shRNAs targeting KLF5(sh36 and sh37) (A, C), and Ctrl and KLF5 indicate the pSin vector control and pSin-KLF5 expression construct, respectively (B, D). *, P < 0.05; **, P < 0.01.