期刊
JOURNAL OF MOLECULAR ENDOCRINOLOGY
卷 42, 期 3-4, 页码 205-214出版社
BIOSCIENTIFICA LTD
DOI: 10.1677/JME-08-0033
关键词
-
资金
- Chang Gung Memorial Hospital [CMRPD170471]
- Terry Fox Cancer Foundation [SMRPG340041]
- Taiwan National Science Council [93-2314-B-182A-092, 97-2320-B-182-023-MY3]
Thioredoxin-interacting protein (TXNIP), also known as vitamin-D-3 upregulated protein 1, interacts with reduced thioredoxin. This protein modulates the cellular redox state and plays a role in stress-induced cellular apoptosis. This study examined TXNIP gene expression in prostate cancer cells. In vitro studies by immunoblot assay have shown that elevated glucose levels (1-15 mM) upregulate TXNIP gene expression two- to fourfold inhuman prostate carcinoma cells (LNCaP) and hepatocellular carcinoma cells (HepG2). Transient gene expression assays reveal that the promoter activity of the TXNIP gene is upregulated by glucose, 3-O-methylglucose, and maltose, but not by mannitol. These results suggest that glucose and 3-O-methylglucose induce TXNIP expression through both glucose metabolism-dependent and -independent pathways. Cotransfection of a plasmid expression carbohydrate response element-binding protein (ChREBP) with a TXNIP reporter vector into LNCaP cells dramatically enhances reporter activity in a low glucose (1 mM) condition. The effects of glucose are apparently mediated in a region located -341 to -324 bp upstream of the translational starting point of the TXNIP gene as indicated by 5'-deletion and site-directed mutagenesis reporter assays. Mutation of the putative carbohydrate response element (ChoRE) from CACGAGGGCAGCACGAG to TTTGAGGGCAGCACGAG abolishes glucose upregulation of TXNIP promoter activity. The present study demonstrates that TXNIP is transcription induced in both LNCaP and HepG2 cells in an increased glucose metabolism-dependent or -independent response, and a putative glucose regulatory system including ChREBP and ChoRE is needed for glucose-induced TXNIP gene in human prostate carcinoma cells. Journal of Molecular Endocrinology (2009) 42, 205-214
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据