Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2010 Oct;24(7):1089-96.
doi: 10.1016/j.bbi.2010.04.013. Epub 2010 May 11.

Glucocorticoids activate Epstein Barr virus lytic replication through the upregulation of immediate early BZLF1 gene expression

Eric V Yang  1 , Jeanette I Webster Marketon, Min Chen, Kwok Wai Lo, Seung-jae Kim, Ronald Glaser
Affiliations

Glucocorticoids activate Epstein Barr virus lytic replication through the upregulation of immediate early BZLF1 gene expression

Eric V Yang et al. Brain Behav Immun. 2010 Oct.

Abstract

Psychological stress-associated immune dysregulation has been shown to disrupt the steady-state expression and reactivate latent herpes viruses. One such virus is the Epstein Barr virus (EBV), which is associated with several human malignancies. EBV infects >90% of people living in North America and persists for life in latently infected cells. Although several studies have shown that glucocorticoids (GCs) can directly induce reactivation of the latent virus, the mechanism of stress hormone involvement in the control of EBV gene expression is not well understood. In this study, we tested the hypothesis that GCs can induce the latent EBV genome to lytically replicate through the induction of the EBV immediate early gene BZLF1 which encodes the lytic transactivator protein ZEBRA. We show a dose-dependent upregulation of BZLF1 mRNA expression by hydrocortisone (HC) and dexamethasone (Dex) in Daudi cells, an EBV genome positive Burkitt's lymphoma cell line, and Dex-induction of the early gene products BLLF3 (encoding for the EBV dUTPase) and BALF5 (encoding for the EBV DNA polymerase). We show that Daudi cells express glucocorticoid receptors (GR) that mediate Dex-dependent upregulation of BZLF1 mRNA levels. This effect was inhibited by both the glucocorticoid receptor antagonist RU486 and by cycloheximide. The results suggest that GCs, in addition to inducing stress-related immune dysregulation, can mediate latent EBV reactivation through the induction of the BZLF1 gene.

PubMed Disclaimer

Conflict of interest statement

Conflict of Interest Statement: All authors declare that there are no conflicts of interest.

Figures

Figure 1
Figure 1
The GC-dependent upregulation of EBV BZLF1 mRNA levels in Daudi cells is mediated by GR. Real-time PCR quantification of EBV BZLF1 mRNA levels in Daudi cells after treatment with HC (A) or Dex (B). Cells were collected after 6, 12, 24, 48, and 72 hrs. Total RNA was isolated and BZLF1 mRNA levels (normalized to GAPDH mRNA levels) were measured using real-time PCR. (C) Western blot showing the expression of GR in Daudi cells. (D) Real-time PCR assay measuring EBV BZLF1 mRNA levels in Daudi cells after treatment with Dex, RU486, or Dex plus RU486 for 6, 12, and 24 hrs to assess the role of GR in the Dex-dependent modulation of BZLF1 gene expression. Values are presented as fold change from untreated control levels. Error bars represent the means ± SD, n = 4; *, p ≤ 0.05; #, p ≤ 0.001.
Figure 2
Figure 2
The GCs HC and Dex modulate BZLF1, BLLF3, and BALF5 mRNA expression in Daudi and B98-5 cells with different kinetics from chemical induction with TPA/NaB. Real-time PCR quantification of EBV BZLF1 (A), BLLF3 (C), and BALF5 (D) mRNA in untreated Daudi cells and after treatment with HC, Dex, and TPA/NaB for 3, 6, 12, 24, 48, and 72 hrs. Modulation of BZLF1 gene expression in Daudi cells was compared to that observed in B95-8 cells after treatment with HC, Dex, and TPA/NaB (B). Values are presented as fold change from untreated control levels. Error bars represent the means ± SD, n = 4; *, p ≤ 0.05; #, p ≤ 0.001. (E) Western blot analysis showing the protein expression of ZEBRA, and EAs in untreated Daudi cells and after treatment with HC, Dex, and TPA/NaB for 3, 6, 12, 24, 48, and 72 hrs.
Figure 3
Figure 3
Dex- and TPA/NaB-dependent upregulation of BZLF1 gene expression is inhibited by cycloheximide. Real-time PCR quantification of EBV BZLF1 mRNA in untreated Daudi cells and after treatment with Dex, Dex plus CHX, TPA/NaB, and TPA/NaB plus CHX for 6, 12, and 24 hrs. Values are presented as fold change from untreated control levels. Error bars represent the means ± SD, n = 4; *, p ≤ 0.05; #, p ≤ 0.001.
Figure 4
Figure 4
Increased GR expression in EBV positive epithelial cells stimulates Dex-mediated BZLF1 mRNA expression. Western blot showing expression of GR after transfection of 0.75, 1.5, or 3 μg of a GR expression plasmid and real-time PCR quantification of EBV BZLF1 in C666-1 (A) and D98/HR-1 (B) cells after growth for 24 hr in the presence or absence of 100 nM Dex. Values are presented as fold change from untreated control levels. Error bars represent the means ± SD, (A) n = 5, (B) n = 6; *, p ≤ 0.05; #, p ≤ 0.001.
See this image and copyright information in PMC

References

    1. Bauer G. Induction of Epstein-Barr virus early antigens by corticosteroids: Inhibition by TPA and retinoic acid. International Journal of Cancer. 1983;31:291–295. - PubMed
    1. Buchwald D, Umali P, Umali J, Kith P, Pearlman T, Komaroff AL. Chronic fatigue and the chronic fatigue syndrome: prevalence in a Pacific Northwest health care system. Annals of Internal Medicine. 1995;123:81–88. - PubMed
    1. Cacioppo J, Kiecolt-Glaser J, Malarkey W, Laskowski B, Rozlog L, Poehlmann K, Burleson M, Glaser R. Autonomic and glucocorticoid associations with the steady-state expression of latent Epstein-Barr virus. Hormones and Behavior. 2002;42:32–41. - PubMed
    1. Cheung ST, Huang DP, Hui AB, Lo KW, Ko CW, Tsang YS, Wong N, Whitney BM, Lee JC. Nasopharyngeal carcinoma cell line (C666-1) consistently harbouring Epstein-Barr virus. International Journal of Cancer. 1999;83:121–126. - PubMed
    1. Chrousos GP, Loriaux DL, Brandon D, Shull J, Renquist D, Hogan W, Tomita M, Lipsett MB. Adaptation of the mineralocorticoid target tissues to the high circulating cortisol and progesterone plasma levels in the squirrel monkey. Endocrinology. 1984;115:25–32. - PubMed

Publication types

MeSH terms