Liver Cancer
Copyright ©The Author(s) 2005. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Aug 7, 2005; 11(29): 4472-4477
Published online Aug 7, 2005. doi: 10.3748/wjg.v11.i29.4472
Down-regulation of PTEN expression due to loss of promoter activity in human hepatocellular carcinoma cell lines
Dong-Zhu Ma, Zhen Xu, Yu-Long Liang, Jian-Ming Su, Zeng-Xia Li, Wen Zhang, Li-Ying Wang, Xi-Liang Zha
Dong-Zhu Ma, Zhen Xu, Yu-Long Liang, Jian-Ming Su, Zeng-Xia Li, Wen Zhang, Li-Ying Wang, Xi-Liang Zha, Ministry of Health Key Laboratory of Glycocojugate Research, Department of Biochemistry and Molecular Biology, Shanghai Medical College, Fudan University, Shanghai 200032, China
Author contributions: All authors contributed equally to the work.
Supported by the National Natural Science Foundation of China, No. 39970338; Shanghai Municipal Government Science and Technology Committee, No. 00JC14042; and Innovation fund of Fudan University, CQF109801
Correspondence to: Professor Xi-Liang Zha, Department of Biochemistry and Molecular Biology, Shanghai Medical College, Fudan University, 138 Yixueyuan Road, Shanghai 200032, China. xlzha@shmu.edu.cn
Telephone: +86-21-54237696 Fax: +86-21-64179832
Received: March 30, 2004
Revised: May 10, 2004
Accepted: May 13, 2004
Published online: August 7, 2005
Abstract

AIM: To investigate the regulation of phosphatase and tensin homolog deleted on chromosome ten (PTEN) gene expression in human hepatocellular carcinoma (HCC) cell lines.

METHODS: The mRNA and protein levels of PTEN were detected by Northern blot and Western blot in HCC cell lines, respectively. Plasmids containing different fragments of PTEN promoter with Luciferase reporter were constructed and transiently transfected into HCC cell lines to study the promoter activity. DNA analysis and RT-PCR were performed to detect the mutation of PTEN promoter and PTEN cDNA.

RESULTS: Either protein or mRNA levels of PTEN in L02 cells (as a control) were significantly higher than that in HCC cell lines. The profile of PTEN promoter activity in 8 cell lines was closely correlated with levels of PTEN mRNA and PTEN protein. Furthermore, the sequence analysis of 8 cells lines showed no mutation in the region of PTEN promoter and PTEN cDNA.

CONCLUSION: PTEN expression is down-regulated in HCC cell lines probably due to loss of activity of PTEN promoter.

Keywords: Phosphatase; Tensin homolog; Hepatocellular carcinoma