Hepatitis B viral X protein alters the biological features and expressions of DNA repair enzymes in LO2 cells.

Abstract

OBJECTIVES:

This study aimed at examining the effects of hepatitis B viral X protein (HBx) on the biological features and the expression of DNA repair enzymes in non-tumour human hepatic LO2 cells in vitro.

METHODS:

The HBx gene was transfected into LO2 cells to establish stably HBx-expressing LO2/HBx cells. The morphological features, cell growth, cell cycle, apoptosis and colony formation of LO2/HBx cells, vector-transfected LO2/pcDNA3.1 cells and unmanipulated LO2 cells were studied. The expressions of DNA repair enzymes and DNA oxidative stress-related 8-hydroxydeoxyguanosine (8-OHdG) were determined by a real-time quantitative polymerase chain reaction assay and high-performance liquid chromatography coupled with electrochemical detection respectively.

RESULTS:

In comparison with controls, significant morphological changes, faster growth, higher frequency of cells at the S phase, but lower at G0/G1 and M/G2 phases, a lower frequency of natural cell apoptosis and a higher percentage of colony formation were observed in the LO2/HBx cells. Furthermore, significantly higher levels of intracellular 8-OHdG and lower levels of human DNA glycosylase alpha (hMYHalpha) mRNA transcripts, but no significant change in human 8-oxoguanine DNA glycosylase 1 (hOGG1), were detected in the LO2/HBx cells.

CONCLUSIONS:

Our data indicated that HBx promoted growth and malignant transformation of non-tumour hepatic LO2 cells in vitro, which was associated with the downregulation of hMYHalpha expression and accumulation of mutagenic DNA adduct 8-OHdG.

• Authors: Bin Cheng, Yaochu Zheng, Xiaorong Guo, Ying Wang, Chunyan Liu
• Journal: Liver international : official journal of the International Association for the Study of the Liver (Liver Int) Vol. 30 Issue 2 Pg. 319-26 (Feb 2010) ISSN: 1478-3231 [Electronic] United States
• PMID: 19968784 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Formazans
• Tetrazolium Salts
• Trans-Activators
• Viral Regulatory and Accessory Proteins
• hepatitis B virus X protein
• MTT formazan
• 8-Hydroxy-2'-Deoxyguanosine
• DNA Glycosylases
• Deoxyguanosine

Topics

• 8-Hydroxy-2'-Deoxyguanosine
• Apoptosis (genetics)
• Cell Cycle (genetics)
• Cell Line
• Cell Survival (genetics)
• Cell Transformation, Neoplastic (genetics)
• Colony-Forming Units Assay
• DNA Glycosylases (genetics, metabolism)
• Deoxyguanosine (analogs & derivatives, metabolism)
• Down-Regulation
• Formazans
• Hepatitis B
• Hepatitis B virus (genetics)
• Hepatocytes (enzymology)
• Humans
• Oxidative Stress (genetics)
• Tetrazolium Salts
• Trans-Activators (physiology)
• Viral Regulatory and Accessory Proteins