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Isolation and Quantification of Epstein-Barr Virus from the P3HR1 Cell Line
Published on: September 28, 2022
Epstein-Barr virus encoded LMP1 downregulates TCL1 oncogene through miR-29b.
E Anastasiadou1, F Boccellato, S Vincenti
1Department of Experimental Medicine and Pathology, Istituto Pasteur-Fondazione Cenci-Bolognetti, La Sapienza University, Rome, Italy.
Oncogene
|December 8, 2009
Summary
Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) inhibits lymphoma growth by upregulating microRNA-29b (miR-29b), which suppresses the oncogene TCL1. This mechanism explains LMP1's dual role in B-cell transformation and growth inhibition.
Area of Science:
- Oncology
- Virology
- Molecular Biology
Background:
- Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) has a dual role, promoting transformation yet inhibiting growth in B-cell lymphomas.
- The molecular mechanisms behind LMP1's growth-inhibitory effects, particularly in Burkitt's lymphoma (BL) and diffuse large B-cell lymphoma (DLBCL), are not well understood.
Purpose of the Study:
- To investigate the molecular mechanisms by which LMP1 exerts its growth-inhibitory effects in B-cell lymphomas.
- To determine if LMP1 regulates oncogenes and microRNAs (miRs) involved in B-cell lymphoma pathogenesis.
Main Methods:
- MicroRNA profiling of LMP1-expressing cells.
- Investigating the role of miR-29b in regulating the oncogene TCL1.
- Utilizing locked nucleic acid (LNA) antisense oligonucleotides to inhibit miR-29b.
- Assessing the involvement of p38 mitogen-activated protein kinase (MAPK) signaling.
Main Results:
- LMP1 was found to negatively regulate the oncogene TCL1 in DLBCL and BL cells.
- MicroRNA profiling revealed upregulation of miR-29b in LMP1-expressing cells.
- LMP1 induced miR-29b expression via its CTAR1 and CTAR2 regions, leading to TCL1 downregulation.
- Inhibition of miR-29b using LNA restored TCL1 expression, confirming LMP1's regulatory pathway.
- p38 MAPK activation by LMP1 was crucial for miR-29b induction and subsequent TCL1 suppression.
Conclusions:
- LMP1 inhibits B-cell lymphoma growth by upregulating miR-29b, which in turn suppresses the oncogene TCL1.
- This miR-29b-mediated downregulation of TCL1 by LMP1 provides a molecular explanation for its cytostatic effects in lymphomas.
- The dual role of LMP1 in B-cell transformation and growth inhibition may depend on expression levels, cell type, and miR regulation.
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