R. Zhao, X. Q. Liu, X. P. Wu, Y. F. Liu, Z. Y. Zhang, G. Y. Yang, S. Guo, J. Niu, J. Y. Wang and K. S. Xu. Vascular endothelial growth factor (VEGF) enhances gastric carcinoma invasiveness via integrin alpha(v)beta6. Cancer Letters, 2010, 287(2): 150- 156.