Background: Vascular endothelial growth inhibitor (VEGI) has been implicated in the regulation of tumour-related vasculature in certain solid tumours. However, its role in urothelial tumours is still unclear. In the present study, the role played by VEGI in urothelial tumours of the bladder was investigated.
Materials and methods: The expression of VEGI was examined in cancer human bladder tissues and in a serial of cell lines using immunochemical staining and RT-PCR respectively. The biological impact of modifying VEGI expression in urothelial cancer cells was evaluated using in vitro models.
Results: VEGI mRNA was expressed in a wide variety of human cell lines. VEGI expression was seen in normal urothelial and stromal cells, but was found to be reduced or absent in urothelial cancer cells. The positive staining in normal tissue (6/7) was significantly higher than that of urothelial cancer tissues (2/12), p=0.006. Moreover, overexpression of VEGI reduced the motility and adhesion of urothelial cancer cells in vitro. However, the overexpression of VEGI had no bearing on the growth and invasion of urothelial cancer cells.
Conclusion: VEGI has an inhibitory effect on cellular motility and adhesion in bladder cancer cells. Taken together with the expression pattern of VEGI in urothelial cancer of the bladder, it suggests that VEGI functions as a negative regulator of aggressiveness during development and progression of bladder cancer.