Original Article
Copyright ©2011 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Aug 14, 2011; 17(30): 3487-3496
Published online Aug 14, 2011. doi: 10.3748/wjg.v17.i30.3487
Integrin-linked kinase in gastric cancer cell attachment, invasion and tumor growth
Gang Zhao, Li-Li Guo, Jing-Yong Xu, Hua Yang, Mei-Xiong Huang, Gang Xiao
Gang Zhao, Jing-Yong Xu, Hua Yang, Mei-Xiong Huang, Gang Xiao, Department of General Surgery, Beijing Hospital, Peking University, 100730 Beijing, China
Li-Li Guo, Department of Ophthalmology, People’s Hospital, Peking University, 100044 Beijing, China
Author contributions: Zhao G, Huang MX and Xiao G designed the research; Zhao G, Guo LL and Xu JY performed the experiments; Zhao G and Yang H analyzed the data; Zhao G and Xiao G provided financial support for this work; Zhao G wrote the manuscript.
Supported by Grants from the Ministry of Human Resources and Social Security of China
Correspondence to: Xiao Gang, Professor, Department of General Surgery, Beijing Hospital, Peking University, 100730 Beijing, China. xiaogang_china@hotmail.com
Telephone: +86-10-85136162 Fax: +86-10-65132969
Received: November 5, 2010
Revised: February 15, 2011
Accepted: February 22, 2011
Published online: August 14, 2011
Abstract

AIM: To investigate the effects of integrin-linked kinase (ILK) on gastric cancer cells both in vitro and in vivo.

METHODS: ILK small interfering RNA (siRNA) was transfected into human gastric cancer BGC-823 cells and ILK expression was monitored by real-time quantitative polymerase chain reaction, Western blotting analysis and immunocytochemistry. Cell attachment, proliferation, invasion, microfilament dynamics and the secretion of vascular endothelial growth factor (VEGF) were also measured. Gastric cancer cells treated with ILK siRNA were subcutaneously transplanted into nude mice and tumor growth was assessed.

RESULTS: Both ILK mRNA and protein levels were significantly down-regulated by ILK siRNA in human gastric cancer cells. This significantly inhibited cell attachment, proliferation and invasion. The knockdown of ILK also disturbed F-actin assembly and reduced VEGF secretion in conditioned medium by 40% (P < 0.05). Four weeks after injection of ILK siRNA-transfected gastric cancer cells into nude mice, tumor volume and weight were significantly reduced compared with that of tumors induced by cells treated with non-silencing siRNA or by untreated cells (P < 0.05).

CONCLUSION: Targeting ILK with siRNA suppresses the growth of gastric cancer cells both in vitro and in vivo. ILK plays an important role in gastric cancer progression.

Keywords: Gastric cancer; Integrin-linked kinase; Small interfering RNA; Cell attachment; Cell proliferation; Cell invasion; Cell microfilament dynamics; Vascular endothelial growth factor; Nude mice