Published online Feb 15, 2000. doi: 10.3748/wjg.v6.i1.89
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.