J Korean Med Sci.  1998 Apr;13(2):171-178. 10.3346/jkms.1998.13.2.171.

Different protein-binding patterns in the P3 promoter region of the human insulin-like growth factor II gene in the human liver cirrhosis and hepatocellular carcinoma tissues

• Seo JH
• Kim KW
• Park BC

• KMID: 1064965
• DOI: http://doi.org/10.3346/jkms.1998.13.2.171

Abstract

The P3 promoter of the human insulin-like growth factor II (IGF-II) is the major IGF-II promoter in fetal liver (FL) and hepatocellular carcinoma (HCC). However, little information is available on the transcriptional factors (TFs) controlling IGF-II gene expression in human liver cirrhosis (LC) and HCC tissues. To evaluate the protein-binding patterns in the P3 promoter region, we performed electromobility shift assay (EMSA) and DNase I footprinting assay using nuclear extracts from human FL, LC and HCC tissues. EMSA showed considerable differences in binding patterns of proteins to P3 promoter region according to different nuclear extracts used in this study. By footprinting assay, eight footprints were observed in extracts. In addition, LC extract showed two specific binding at L1 [-80:+30] and L2 [-126:-80] regions, and HCC showed two specific binding at H1 [-176:-120] and H2 [-210:-177] as well as two liver specific binding (L1 and L2). Footprinting after immunoprecipitation indicates that Egr1, Egr2 and Sp1 could bind to P3 promoter directly, while c-jun and c-fos could not bind to these region directly. Further study is required to determine the function of these proteins.

MeSH Terms

Adult
Carcinoma, Hepatocellular/pathology
Carcinoma, Hepatocellular/metabolism*
DNA Footprinting
DNA-Binding Proteins/metabolism*
Hela Cells
Human
Insulin-Like Growth Factor II/metabolism
Insulin-Like Growth Factor II/genetics*
Liver Cirrhosis/pathology
Liver Cirrhosis/metabolism*
Liver Neoplasms/pathology
Liver Neoplasms/metabolism*
Precipitin Tests
Promoter Regions (Genetics)*
Tumor Cells, Cultured