The aims of the current study were to determine whether 786‑0
renal cancer cell‑derived exosomes promote human umbilical vein endothelial cells (HUVECs) to form tubular structures and to uncover the underlying mechanisms associated with this process. Exosomes were extracted and purified using ultrafiltration and
sucrose gradient centrifugation and characterized by transmission electron microscopy. Tubular structure formation was observed using the
matrigel tubular assay. In addition, an adenovirus vector was used to transfect the hepatocyte
cell adhesion molecule (hepaCAM) gene into
renal cancer 786‑0 cells. The expression of hepaCAM and
vascular endothelial growth factor (
VEGF)
mRNA and
protein was determined by reverse transcription‑polymerase chain reaction and western blot analysis, respectively.
Tumor cell‑derived exosomes were observed to significantly increase tubular formation in HUVECs. Following transfection with the hepaCAM gene,
VEGF expression in 786‑0 cells was markedly decreased. In HUVECs, exosome treatment increased
VEGF mRNA and
protein expression, while hepaCAM expression was only decreased at the
protein level. In the present study,
renal cancer 786‑0 cell‑derived exosomes significantly promoted angiogenesis via upregulation of
VEGF expression in HUVECs, which may be induced by the downregulation of hepaCAM.