Original Articles
Copyright ©The Author(s) 2000. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Feb 15, 2000; 6(1): 89-92
Published online Feb 15, 2000. doi: 10.3748/wjg.v6.i1.89
Tumor growth inhibition effect of hIL-6 on colon cancer cells transfected with the target gene by retroviral vector
Bing Xiao, Bo Jing, Ya-Li Zhang, Dian-Yuan Zhou, Wan-Dai Zhang
Bing Xiao, Bo Jing, Ya-Li Zhang, Dian-Yuan Zhou, Wan-Dai Zhang, Institute of Gastroenterology, Nanfang Hospital, the First Military Medical University, Guangzhou 510515, Guangdong Province, China
Bing Xiao, man, born in 1962-09-12 in Fujian of China. He received a bachelor degree from Fujian Chinese Medical College in 1984, and received Ph.D. from the First Military Medical University in 1996, now associate professor, specialized in gene therapy and gene cloning.
Author contributions: All authors contributed equally to the work.
Correspondence to: Bing Xiao, Institute of Gastroenterology, Nanfang Hospital, The First Military Medical University, Tonghe Road, Guangzhou 510515, Guangdong Province, China
Telephone: +86-20-85141544(O)
Received: June 14, 1999
Revised: August 22, 1999
Accepted: September 11, 1999
Published online: February 15, 2000

AIM: To observe the tumor inhibitory effects by transfecting I L-6 cDNA into colon cancer cell line HT-29 with retroviral vector pZIP cDNA.

METHODS: Human IL-6 gene was reconstructed in retrovirus vector and transfected into incasing cells PA317 by lipofectamine mediated method, the clones of the cells transferred with hIL-6 were selected by G418, and targeted HT-29 cells were infected with the virus granules secreted from PA317 and also selected by G418. Test gene transcription and expression level by hybridization , ELISA and MTT assay, etc. Analyze tumor inhibitory effects according to the cell growth curve, plating forming rate and tumorigenicity in nude mice.

RESULT: Successfully constructed and transfected recombinant exp ressing vectors pZIPIL-6 cDNA and got positive transfected cell lines. The colon cancer cell line (HT-29 IL-6) transfected with the hIL-6 gene by retroviral vector was established. The log proliferation period and the doubling time of t his cell line was between 4 to 7 days and 2.5 days according to the direct cell count, the cell proliferation was obviously inhibited with MTT assay, the plating inhibitory rate was 50% by plating efficiency test. When HT-29 IL-6 cells w ere inoculated into the nude mice subcutaneously, carcinogenic activity of the solid tumor was found superior to the control group and the size of tumor was not significantly enlarged. Injection of combination virus fluid containing IL-6 gene into transplantation tumors could inhibit the growth and development of the tumor.

CONCLUSION: IL-6 could inhibit the growth and proliferation of colon cancer cells by retroviral vector-mediated transduction.

Keywords: interleukin-6 gene, gene transfection, gene therapy, colonic neoplasms