The influence of human single chain inteleukin-12 gene transduction on the biological behavior of hepatoma 7721 cells.

Abstract

OBJECTIVE:

To investigate the anti-tumor effects of human single chain interleukin-12 (hscIL-12).

METHOD:

pcDNA/hscIL-12 recombinant was transfected into human hepatic carcinoma cells (7721 cells) by lipofectin method. The 7721/hscIL-12 cells which secrete hscIL-12 stably, were obtained via G418 selection, and in vitro the influence of hscIL-12 gene transduction on the growth of tumor cells was evaluated by cell cycle analysis. In vivo, genetically engineered 7721 cells (7721/hscIL-12, 7721/pcDNA) and parental cells were implanted into BALB/c nude mice, respectively. 7721/pcDNA and 7721/hscIL-12 groups were divided into two sub-groups on day 8: one was administered with hPBL twice, 6 days at interval; the other was given equal volume of PBS. Mice were sacrificed on day 26, and spleens and tumors were taken out for histologic assay.

RESULTS:

hscIL-12 produced stably by 7721/hscIL-12 cells had bioactivity, and it was proved by Western blot, immunocytochemistry, and in situ hybridization. In vitro, compared with 7721 and 7721/pcDNA, the 7721/hscIL-12 grew much more slowly. FACS assay showed apparent G1 arrest of 7721/hscIL-12 cells. In animal experiment, on day 8 after inoculation, the tumors of 7721 and 7721/pcDNA group were up to 5 approximately 7 mm, while those of 7721/hscIL-12 group were 2 approximately 4 mm. When treated with hPBL, the tumor of 7721/hscIL-12 group disappeared completely. Histologically, the tumors from 7721/hscIL-12 without hPBL treatment had numerous lymphocyte infiltration, the tumor cells displayed depression looking, atrophy, focal necrosis and apoptosis, whereas the tumors of 7721 and 7721/pcDNA groups grew thrivingly.

CONCLUSION:

hscIL-12 transduced 7721 cells could induced significant antitumor immune response which resulted in tumor regression totally when the hPBL was inoculated, and also hscIL-12 has certain effects on mice immune system. These findings suggest that hscIL-12 and hscIL-12 gene therapy might have promising prospects in clinical application.

• Authors: L Jin, B Lai, Y Geng, Y Wang, L Si
• Journal: Chinese medical sciences journal = Chung-kuo i hsueh k'o hsueh tsa chih (Chin Med Sci J) Vol. 16 Issue 3 Pg. 147-52 (Sep 2001) ISSN: 1001-9294 [Print] China
• PMID: 12899326 (Publication Type: Journal Article)

Chemical References

• Interleukin-12

Topics

• Animals
• Carcinoma, Hepatocellular (metabolism, pathology, therapy)
• Cell Division
• Genetic Therapy
• Humans
• Interleukin-12 (biosynthesis, genetics)
• Liver Neoplasms (metabolism, pathology, therapy)
• Male
• Mice
• Mice, Inbred BALB C
• Mice, Nude
• Neoplasm Transplantation
• Transduction, Genetic
• Tumor Cells, Cultured