Abstract
The stable expression of the Epstein-Barr virus (EBV) latent membrane protein (LMP) in certain EBV-negative Burkitt's lymphoma cell lines correlates with an increased expression of the oncogene Bcl-2 (S. Henderson, M. Rowe, C. Gregory, D. Croom-Carter, F. Wang, R. Longnecker, E. Kieff, and A. Rickinson, Cell 65:1107-1115, 1991). This finding is consistent with a model in which Bcl-2 contributes to the immortalization of B cells mediated by EBV. We therefore asked whether the expression of Bcl-2 protein correlates with the induction of three cellular phenotypes induced by or associated with LMP. The expression of Bcl-2 in primary B cells infected with the B95-8 strain of EBV varied between 1 and 1.8 times that in uninfected cells when 50% of the cells were infected, expressed LMP, and incorporated 20-fold more [3H]thymidine than did uninfected cells. This finding indicates that induced proliferation of these primary cells is not sufficient to induce Bcl-2. We found that BALB/c 3T3 cells and their derivatives transformed by LMP do not express Bcl-2 detectably. The expression of LMP at high levels in lymphoid cells is cytotoxic and correlates with an increased expression of Bcl-2 following stable selection for the introduced LMP gene; 2 days after transfection, control vector- and LMP-transfected populations, however, express equal levels of Bcl-2 protein. We also analyzed transient expression of LMP in an EBV-negative Burkitt's lymphoma cell line. Infection of BJAB cells with the B95-8 strain of EBV results in an increase in Bcl-2 expression with a time course similar to that of LMP expression, and LMP alone transiently induces an increase in Bcl-2 expression in these cells. We interpret these observations to indicate that increased expression of Bcl-2 is unlikely to contribute to the ability of EBV to immortalize primary B cells and that both the transformation of rodent cells and the cytotoxicity mediated by LMP are independent of Bcl-2.
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- Aaronson S. A., Todaro G. J. Development of 3T3-like lines from Balb-c mouse embryo cultures: transformation susceptibility to SV40. J Cell Physiol. 1968 Oct;72(2):141–148. doi: 10.1002/jcp.1040720208. [DOI] [PubMed] [Google Scholar]
- Baichwal V. R., Sugden B. Posttranslational processing of an Epstein-Barr virus-encoded membrane protein expressed in cells transformed by Epstein-Barr virus. J Virol. 1987 Mar;61(3):866–875. doi: 10.1128/jvi.61.3.866-875.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Baichwal V. R., Sugden B. The multiple membrane-spanning segments of the BNLF-1 oncogene from Epstein-Barr virus are required for transformation. Oncogene. 1989 Jan;4(1):67–74. [PubMed] [Google Scholar]
- Baichwal V. R., Sugden B. Transformation of Balb 3T3 cells by the BNLF-1 gene of Epstein-Barr virus. Oncogene. 1988 May;2(5):461–467. [PubMed] [Google Scholar]
- Bakhshi A., Jensen J. P., Goldman P., Wright J. J., McBride O. W., Epstein A. L., Korsmeyer S. J. Cloning the chromosomal breakpoint of t(14;18) human lymphomas: clustering around JH on chromosome 14 and near a transcriptional unit on 18. Cell. 1985 Jul;41(3):899–906. doi: 10.1016/s0092-8674(85)80070-2. [DOI] [PubMed] [Google Scholar]
- Cleary M. L., Sklar J. Nucleotide sequence of a t(14;18) chromosomal breakpoint in follicular lymphoma and demonstration of a breakpoint-cluster region near a transcriptionally active locus on chromosome 18. Proc Natl Acad Sci U S A. 1985 Nov;82(21):7439–7443. doi: 10.1073/pnas.82.21.7439. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cleary M. L., Smith S. D., Sklar J. Cloning and structural analysis of cDNAs for bcl-2 and a hybrid bcl-2/immunoglobulin transcript resulting from the t(14;18) translocation. Cell. 1986 Oct 10;47(1):19–28. doi: 10.1016/0092-8674(86)90362-4. [DOI] [PubMed] [Google Scholar]
- Gregory C. D., Dive C., Henderson S., Smith C. A., Williams G. T., Gordon J., Rickinson A. B. Activation of Epstein-Barr virus latent genes protects human B cells from death by apoptosis. Nature. 1991 Feb 14;349(6310):612–614. doi: 10.1038/349612a0. [DOI] [PubMed] [Google Scholar]
- Hammerschmidt W., Sugden B., Baichwal V. R. The transforming domain alone of the latent membrane protein of Epstein-Barr virus is toxic to cells when expressed at high levels. J Virol. 1989 Jun;63(6):2469–2475. doi: 10.1128/jvi.63.6.2469-2475.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hammerschmidt W., Sugden B. Genetic analysis of immortalizing functions of Epstein-Barr virus in human B lymphocytes. Nature. 1989 Aug 3;340(6232):393–397. doi: 10.1038/340393a0. [DOI] [PubMed] [Google Scholar]
- Henderson S., Rowe M., Gregory C., Croom-Carter D., Wang F., Longnecker R., Kieff E., Rickinson A. Induction of bcl-2 expression by Epstein-Barr virus latent membrane protein 1 protects infected B cells from programmed cell death. Cell. 1991 Jun 28;65(7):1107–1115. doi: 10.1016/0092-8674(91)90007-l. [DOI] [PubMed] [Google Scholar]
- Hockenbery D., Nuñez G., Milliman C., Schreiber R. D., Korsmeyer S. J. Bcl-2 is an inner mitochondrial membrane protein that blocks programmed cell death. Nature. 1990 Nov 22;348(6299):334–336. doi: 10.1038/348334a0. [DOI] [PubMed] [Google Scholar]
- Klein G., Lindahl T., Jondal M., Leibold W., Menézes J., Nilsson K., Sundström C. Continuous lymphoid cell lines with characteristics of B cells (bone-marrow-derived), lacking the Epstein-Barr virus genome and derived from three human lymphomas. Proc Natl Acad Sci U S A. 1974 Aug;71(8):3283–3286. doi: 10.1073/pnas.71.8.3283. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Knutson J. C., Yee D. Electroporation: parameters affecting transfer of DNA into mammalian cells. Anal Biochem. 1987 Jul;164(1):44–52. doi: 10.1016/0003-2697(87)90365-4. [DOI] [PubMed] [Google Scholar]
- Liebowitz D., Mannick J., Takada K., Kieff E. Phenotypes of Epstein-Barr virus LMP1 deletion mutants indicate transmembrane and amino-terminal cytoplasmic domains necessary for effects in B-lymphoma cells. J Virol. 1992 Jul;66(7):4612–4616. doi: 10.1128/jvi.66.7.4612-4616.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Mark W., Sugden B. Transformation of lymphocytes by Epstein-Barr virus requires only one-fourth of the viral genome. Virology. 1982 Oct 30;122(2):431–443. doi: 10.1016/0042-6822(82)90242-2. [DOI] [PubMed] [Google Scholar]
- Miller G., Lipman M. Release of infectious Epstein-Barr virus by transformed marmoset leukocytes. Proc Natl Acad Sci U S A. 1973 Jan;70(1):190–194. doi: 10.1073/pnas.70.1.190. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nuñez G., Hockenbery D., McDonnell T. J., Sorensen C. M., Korsmeyer S. J. Bcl-2 maintains B cell memory. Nature. 1991 Sep 5;353(6339):71–73. doi: 10.1038/353071a0. [DOI] [PubMed] [Google Scholar]
- Nuñez G., London L., Hockenbery D., Alexander M., McKearn J. P., Korsmeyer S. J. Deregulated Bcl-2 gene expression selectively prolongs survival of growth factor-deprived hemopoietic cell lines. J Immunol. 1990 May 1;144(9):3602–3610. [PubMed] [Google Scholar]
- Rabson M., Heston L., Miller G. Identification of a rare Epstein-Barr virus variant that enhances early antigen expression in Raji cells. Proc Natl Acad Sci U S A. 1983 May;80(9):2762–2766. doi: 10.1073/pnas.80.9.2762. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Reed J. C., Tsujimoto Y., Epstein S. F., Cuddy M., Slabiak T., Nowell P. C., Croce C. M. Regulation of bcl-2 gene expression in lymphoid cell lines containing normal #18 or t(14;18) chromosomes. Oncogene Res. 1989;4(4):271–282. [PubMed] [Google Scholar]
- Reedman B. M., Klein G. Cellular localization of an Epstein-Barr virus (EBV)-associated complement-fixing antigen in producer and non-producer lymphoblastoid cell lines. Int J Cancer. 1973 May;11(3):499–520. doi: 10.1002/ijc.2910110302. [DOI] [PubMed] [Google Scholar]
- Ricksten A., Svensson C., Welinder C., Rymo L. Identification of sequences in Epstein-Barr virus DNA required for the expression of the second Epstein-Barr virus-determined nuclear antigen in COS-1 cells. J Gen Virol. 1987 Sep;68(Pt 9):2407–2418. doi: 10.1099/0022-1317-68-9-2407. [DOI] [PubMed] [Google Scholar]
- Seto M., Jaeger U., Hockett R. D., Graninger W., Bennett S., Goldman P., Korsmeyer S. J. Alternative promoters and exons, somatic mutation and deregulation of the Bcl-2-Ig fusion gene in lymphoma. EMBO J. 1988 Jan;7(1):123–131. doi: 10.1002/j.1460-2075.1988.tb02791.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tsujimoto Y., Finger L. R., Yunis J., Nowell P. C., Croce C. M. Cloning of the chromosome breakpoint of neoplastic B cells with the t(14;18) chromosome translocation. Science. 1984 Nov 30;226(4678):1097–1099. doi: 10.1126/science.6093263. [DOI] [PubMed] [Google Scholar]
- Tsujimoto Y. Overexpression of the human BCL-2 gene product results in growth enhancement of Epstein-Barr virus-immortalized B cells. Proc Natl Acad Sci U S A. 1989 Mar;86(6):1958–1962. doi: 10.1073/pnas.86.6.1958. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Vaux D. L., Cory S., Adams J. M. Bcl-2 gene promotes haemopoietic cell survival and cooperates with c-myc to immortalize pre-B cells. Nature. 1988 Sep 29;335(6189):440–442. doi: 10.1038/335440a0. [DOI] [PubMed] [Google Scholar]
- Wang D., Liebowitz D., Kieff E. An EBV membrane protein expressed in immortalized lymphocytes transforms established rodent cells. Cell. 1985 Dec;43(3 Pt 2):831–840. doi: 10.1016/0092-8674(85)90256-9. [DOI] [PubMed] [Google Scholar]
- Wang D., Liebowitz D., Wang F., Gregory C., Rickinson A., Larson R., Springer T., Kieff E. Epstein-Barr virus latent infection membrane protein alters the human B-lymphocyte phenotype: deletion of the amino terminus abolishes activity. J Virol. 1988 Nov;62(11):4173–4184. doi: 10.1128/jvi.62.11.4173-4184.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wang F., Gregory C., Sample C., Rowe M., Liebowitz D., Murray R., Rickinson A., Kieff E. Epstein-Barr virus latent membrane protein (LMP1) and nuclear proteins 2 and 3C are effectors of phenotypic changes in B lymphocytes: EBNA-2 and LMP1 cooperatively induce CD23. J Virol. 1990 May;64(5):2309–2318. doi: 10.1128/jvi.64.5.2309-2318.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wysocki L. J., Sato V. L. "Panning" for lymphocytes: a method for cell selection. Proc Natl Acad Sci U S A. 1978 Jun;75(6):2844–2848. doi: 10.1073/pnas.75.6.2844. [DOI] [PMC free article] [PubMed] [Google Scholar]