Mutations in the C-terminus of the X protein of hepatitis B virus regulate Wnt-5a expression in hepatoma Huh7 cells: cDNA microarray and proteomic analyses
Cell Line, Tumor
Electrophoresis, Gel, Two-Dimensional
Oligonucleotide Array Sequence Analysis
Reverse Transcriptase Polymerase Chain Reaction
Viral Regulatory and Accessory Proteins
Permanent link to this recordhttp://hdl.handle.net/20.500.12613/5608
MetadataShow full item record
AbstractBackground: The hepatitis B virus x gene (HBx) is a promiscuous transactivator implicated in the development of hepatocellular carcinoma (HCC). The present study was designed to investigate the molecular events regulated by HBx. Methods: Genomic and proteomic expression profiling was performed in Huh7 HCC cells transfected with HBx mutants with a C-terminal deletion. The gene and protein expression of wingless-type murine-mammary-tumour virus (MMTV) integration site family, member 5A (Wnt-5a) was validated by analyses of reverse transcription-polymerase chain reaction (RT-PCR), real-time RT-PCR, western blot and immunohistochemistry. Results: Differentially expressed genes and proteins were found in the transfected Huh7 HCC cells; most of them were involved in transcriptional regulation, although others including oncogenes or tumor suppressor genes, and molecules involved in cell junctions, signal transduction pathways, metabolism or the immune response were also observed. The expression of the Wnt-5a gene was elevated >10-fold in Huh7 cells transfected with the HBx 3′-30 amino acid deletion mutant. However, the expression was downregulated by the transfection with the HBx 3′-40 amino acid deletion mutant. The changes in Wnt-5a expression were also observed in human HCC tissues, compared with corresponding non-cancerous liver tissues. A negative correlation was found between the expression of Wnt-5a and HBx COOH mutations in HCC tissues. Conclusions: HBx mutants may participate in the development and progression of HCC, at least in part through the Wnt-5a pathway. © The Author 2008. Published by Oxford University Press. All rights reserved.
Citation to related workOxford University Press (OUP)
ADA complianceFor Americans with Disabilities Act (ADA) accommodation, including help with reading this content, please contact email@example.com
Showing items related by title, author, creator and subject.
A Spiroligomer α-Helix Mimic That Binds HDM2, Penetrates Human Cells and Stabilizes HDM2 in Cell CultureBrown, ZZ; Akula, K; Arzumanyan, A; Alleva, J; Jackson, M; Bichenkov, E; Sheffield, JB; Feitelson, MA; Schafmeister, CE (2012-10-18)We demonstrate functionalized spiroligomers that mimic the HDM2-bound conformation of the p53 activation domain. Spiroligomers are stereochemically defined, functionalized, spirocyclic monomers coupled through pairs of amide bonds to create spiro-ladder oligomers . Two series of spiroligomers were synthesized, one of structural analogs and one of stereochemical analogs, from which we identified compound 1, that binds HDM2 with a Kd value of 400 nM. The spiroligomer 1 penetrates human liver cancer cells through passive diffusion and in a dose-dependent and time-dependent manner increases the levels of HDM2 more than 30-fold in Huh7 cells in which the p53/HDM2 negative feed-back loop is inoperative. This is a biological effect that is not seen with the HDM2 ligand nutlin-3a. We propose that compound 1 modulates the levels of HDM2 by stabilizing it to proteolysis, allowing it to accumulate in the absence of a p53/HDM2 feedback loop. © 2012 Brown et al.
The retinoblastoma family: Twins or distant cousins?Claudio, PP; Tonini, T; Giordano, A; Giordano, Antonio|0000-0002-5959-016X (2002-09-23)The destiny of a cell - whether it undergoes division, differentiation or death - results from an intricate balance of many regulators, including oncoproteins, tumor-suppressor proteins and cell-cycle-associated proteins. One of the better-studied tumor suppressors is the retinoblastoma protein, known as pRb or p105. Two recently identified proteins, pRb2/p130 and p107, show structural and functional similarities to pRb, and these proteins and their orthologs make up the retinoblastoma (Rb) family. Members of the family have been found in animals and plants, and a related protein is known in the alga Chlamydomonas. Members of the Rb family are bound and inactivated by viral proteins and, in turn, bind cellular transcription factors and repress their function, and can also form complexes with cyclins and cyclin-dependent kinases and with histone deacetylases. The are found in the nucleus and their subnuclear localization depends on binding to the nuclear matrix. Members of the family form part of a signal-transduction pathway called the Rb pathway, which is important in cell-cycle regulation and have roles in growth suppression, differentiation and apoptosis in different organisms and cell types.
Identification of the effector domain of biglycan that facilitates BMP-2 osteogenic functionJongwattanapisan, P; Terajima, M; Miguez, PA; Querido, W; Nagaoka, H; Sumida, N; Gurysh, EG; Ainslie, KM; Pleshko, N; Perera, L; Yamauchi, M; Pleshko, Nancy|0000-0001-8656-3936 (2018-12-01)© 2018 The Author(s). We have reported that recombinant biglycan (BGN) core protein accelerates bone formation in vivo by enhancing bone morphogenetic protein (BMP)-2 function. The purpose of the present study was to identify the specific domain ("effector") within the BGN core protein that facilitates BMP-2 osteogenic function. Thus, we generated various recombinant and synthetic peptides corresponding to several domains of BGN, and tested their effects on BMP-2 functions in vitro. The results demonstrated that the leucine-rich repeats 2-3 domain (LRR2-3) of BGN significantly enhanced the BMP-2 induced Smad1/5/9 phosphorylation, osteogenic gene expression, and alkaline phosphatase activity in myogenic C2C12 cells. Furthermore, addition of LRR2-3 to osteoblastic MC3T3-E1 cells accelerated in vitro mineralization without compromising the quality of the mineral and matrix. These data indicate that LRR2-3 is, at least in part, responsible for BGN's ability to enhance BMP-2 osteogenic function, and it could be useful for bone tissue regeneration.