1887

Abstract

Human papillomavirus type 16 (HPV-16) is a DNA tumour virus that has been implicated in the development of cervical cancer. In non-transformed HPV-infected cells, the HPV E2 protein regulates transcription of the viral E6 and E7 oncogenes. Malignant transformation is usually accompanied by disruption of the E2 gene and consequent deregulated expression of E6 and E7. Here we show that re-introduction of the HPV-16 E2 protein into an HPV-16-transformed cervical carcinoma cell line results in a decrease in growth rate and, in the absence of serum growth factors, cell death via apoptosis. E2 expression increases E6/E7 mRNA levels. This brings about an increase in E7 protein levels, which in turn leads to an increase in free E2F, a condition that has previously been shown to induce apoptotic cell death. Despite the increase in E6 mRNA there is no detectable E6 protein in these cells and E2 expression does not reduce the activity of a p53-responsive promoter. Our data suggest that disruption of the E2 gene produces HPV- transformed cells that are less liable to undergo apoptosis and, therefore, more likely to form cervical tumours.

Loading

Article metrics loading...

/content/journal/jgv/10.1099/0022-1317-78-11-3009
1997-11-01
2024-04-18
Loading full text...

Full text loading...

/deliver/fulltext/jgv/78/11/9367388.html?itemId=/content/journal/jgv/10.1099/0022-1317-78-11-3009&mimeType=html&fmt=ahah

References

  1. Baker C. C., Phelps W. C., Lindgren V., Braun M. J., Gonda M. A., Howley P. M. 1987; Structural and transcriptional analysis of human papillomavirus type 16 sequences in cervical carcinoma cell lines. Journal of Virology 61:962–971
    [Google Scholar]
  2. Bouvard V., Storey A., Pim D., Banks L. 1994; Characterization of the human papillomavirus E2 protein: evidence of trans-activation and trans-repression in cervical keratinocytes. EMBO Journal 13:5451–5459
    [Google Scholar]
  3. Butz K., Shahabeddin L., Geisen C., Spitkovsky D., Ullmann A., Hoppe-Seyler F. 1995; Functional p53 protein in human papillomavirus-positive cancer cells. Oncogene 10:927–936
    [Google Scholar]
  4. Chiang C.-M., Broker T. R., Chow L. T. 1991; An E1M E2C fusion protein encoded by human papillomavirus type 11 is a sequence-specific transcription repressor. Journal of Virology 65:3317–3329
    [Google Scholar]
  5. Chin M. T., Hirochika R., Hirochika H., Broker T. R., Chow L. T. 1988; Regulat ion of human papillomavirus type 11 enhancer and E6 promoter by activating and repressing proteins from the E2 open reading frame: functional and biochemical studies. Journal of Virology 62:2994–3002
    [Google Scholar]
  6. Chong T., Chan W. K., Bernard H. U. 1990; Transcriptional activation of human papillomavirus 16 by nuclear factor I, API, steroid receptors and a possibly novel transcription factor, PVF: a model for the composition of genital papillomavirus enhancers. Nucleic Acids Research 18:465–470
    [Google Scholar]
  7. Cripe T. P., Haugen T. H., Turk J. P., Tabatabai F., Schimd P. G., Durst M., Gissman L., Roman A., Turek L. P. 1987; Transcriptional regulation of the human papillomavirus-16 E6-E7 promoter by a keratinocyte-dependent enhancer, and by viral E2 trans-activator and repressor gene products: implications for cervical carcinogenesis. EMBO Journal 6:3745–3753
    [Google Scholar]
  8. Desaintes C., Demeret C., Goyat S., Yaniv M., Thierry F. 1997; Expression of the papillomavirus E2 protein in HeLa cells leads to apoptosis. EMBO Journal 16:504–514
    [Google Scholar]
  9. Doorbar J., Parton A., Hartley K., Banks L., Crook T., Stanley M., Crawford L. 1990; Detection of novel splicing patterns in a HPV16- containing keratinocyte cell line. Virology 178:254–262
    [Google Scholar]
  10. Dostatni N., Lambert P. P., Sousa R., Ham J., Howley P. M., Yaniv M. 1991; The functional BPV-1 E2 trans-activating protein can act as a repressor by preventing formation of the initiation complex. Genes and Development 5:1657–1671
    [Google Scholar]
  11. Dowhanick J. J., McBride A. A., Howley P. M. 1995; Suppression of cellular proliferation by the papillomavirus E2 protein. Journal of Virology 69:7791–7799
    [Google Scholar]
  12. Dürst M., Kleinheinz A., Hotz M., Gissmann L. 1985; The physical state of human papillomavirus type 16 DNA in benign and malignant genital tumours. Journal of General Virology 66:1515–1522
    [Google Scholar]
  13. Dyson N., Howley P. M., Münger K., Harlow E. 1989; The human papilloma virus-16 E7 oncoprotein is able to bind to the retinoblastoma gene product. Science 243:934–937
    [Google Scholar]
  14. Earnshaw W. C. 1995; Nuclear changes in apoptosis. Current Opinion in Cell Biology 7:337–343
    [Google Scholar]
  15. Frattini M. G., Laimins L. A. 1994; Binding of the human papillomavirus E1 origin-recognition protein is regulated through complex formation with the E2 enhancer-binding protein. Proceedings of the National Academy of Sciences, USA 91:12398–12402
    [Google Scholar]
  16. Frattini M. G., Hurst S. D., Lim H. B., Swaminathan S., Laimins L. A. 1997; Abrogation of a mitotic checkpoint by E2 proteins from oncogenic human papillomaviruses correlates with increased turnover of the p53 tumour suppressor protein. EMBO Journal 16:318–331
    [Google Scholar]
  17. Hawley-Nelson P., Vousden K. H., Hubbert N. L., Lowy D. R., Schiller J. T. 1989; HPV16 E6 and E7 proteins cooperate to immortalize human foreskin keratinocytes. EMBO Journal 8:3905–3910
    [Google Scholar]
  18. Hemström Nilsson C., Bakos E., Petry K.-U., Schneider A., Dürst M. 1996; Promoter usage in the E7 ORF of HPV16 correlates with epithelial differentiation and is largely confined to low-grade neoplasia. International Journal of Cancer 65:6–12
    [Google Scholar]
  19. Howes K. A., Ransom N., Papermaster D. S., Lasudry J. G. H., Albert D. M., Windle J. J. 1994; Apoptosis or retinoblastoma : alternative fates of photoreceptors expressing the HPV-16E7 gene in the presence or absence of p53. Genes and Development 8:1300–1310
    [Google Scholar]
  20. Hubbert N. L., Sedman S. A., Schiller J. T. 1992; Human papillomavirus type 16 E6 increases the degradation rate of p53 in human keratinocytes. Journal of Virology 66:6237–6241
    [Google Scholar]
  21. Hwang E.-S., Riese D. J. H., Settleman J., Nilson L. A., Honig J., Flynn S., DiMaio D. 1993; Inhibition of cervical carcinoma cell line proliferation by introduction of a bovine papillomavirus regulatory gene. Journal of Virology 67:3720–3729
    [Google Scholar]
  22. Hwang E.-S., Naeger L. K., DiMaio D. 1996; Activation of the endogenous p53 growth inhibitory pathway in HeLa cervical carcinoma cells by expression of the bovine papillomavirus E2 gene. Oncogene 12:795–803
    [Google Scholar]
  23. Lechner M. S., Mack D. H., Finicle A. B., Crook T., Vousden K. H., Laimins L. A. 1992; Human papillomavirus E6 proteins bind p53 in vivo and abrogate p53-mediated repression of transcription. EMBO Journal 11:3045–3052
    [Google Scholar]
  24. Lowe S. W., Schmitt E. M., Smith S. W., Osborne B. A., Jacks T. 1993; p53 is required for radiation-induced apoptosis in mouse thymocytes. Nature 362:847–849
    [Google Scholar]
  25. Mohr I. J., Clark R., Sun S., Androphy E. J., MacPherson P., Botchan M. 1990; Targeting the E1 replication protein to the papillomavirus origin of replication by complex formation with the E2 transactivator. Science 250:1694–1699
    [Google Scholar]
  26. Mosmann T. 1983; Rapid colorimetric assay for cellular growth and survival: application to proliferation and cytotoxicity assays. Journal of Immunological Methods 65:55–63
    [Google Scholar]
  27. Münger K., Phelps W. C., Bubb V., Howley P. M., Schlege R. 1989; The E6 and E7 genes of the human papillomavirus type 16 together are necessary and sufficient for transformation of primary human keratinocytes. Journal of Virology 63:4417–4421
    [Google Scholar]
  28. Pan H., Griep A. E. 1994; Altered cell cycle regulation in the lens of HPV-16 E6 or E7 transgenic mice: implications for tumor suppressor gene function in development. Genes and Development 8:1285–1299
    [Google Scholar]
  29. Phelps W. C., Howley P. M. 1987; Transcriptional trans-activation by the human papillomavirus type 16 E2 gene product. Journal of Virology 61:1630–1638
    [Google Scholar]
  30. Qin X.-Q., Livingston D. M., Kaelin W. G.Jr Adams P. D. 1994; Deregulated transcription factor E2F-1 expression leads to S-phase entry and p53-mediated apoptosis. Proceedings of the National Academy of Sciences, USA 91:10918–10922
    [Google Scholar]
  31. Razvi E. S., Welsh R. M. 1995; Apoptosis in viral infections. Advances in Virus Research 45:1–60
    [Google Scholar]
  32. Romanczuk H., Howley P. M. 1992; Disruption of either the E1 or the E2 regulatory gene of human papillomavirus type 16 increases viral immortalization capacity. Proceedings of the National Academy of Sciences, USA 89:3159–3163
    [Google Scholar]
  33. Romanczuk H., Thierry F., Howley P. M. 1990; Mutational analysis of cis elements involved in E2 modulation of human papillomavirus type 16 P97 and type 18 P105 promoters. Journal of Virology 64:2849–2859
    [Google Scholar]
  34. Sambrook J., Fritsch E. F., Maniatis T. 1989 Molecular Cloning: A Laboratory Manual, 2nd edn.. Cold Spring Harbor, NY: Cold Spring Harbor Laboratory;
    [Google Scholar]
  35. Scheffner M., Werness B. A., Huibregtse J. M., Levine A. J., Howley P. M. 1990; The E6 oncoprotein encoded by human papillomavirus types 16 and 18 promotes the degradation of p53. Cell 63:1129–1136
    [Google Scholar]
  36. Schwarz E., Freese U. K., Gissmann L., Mayer W., Roggenbuck B., Stremlau A., zur Hausen H. 1985; Structure and transcription of human papillomavirus sequences in cervical carcinoma cells. Nature 314:111–114
    [Google Scholar]
  37. Smotkin D., Wettstein F. O. 1986; Transcription of human papillomavirus type 16 early genes in a cervical cancer and a cancer- derived cell line and identification of the E7 protein. Proceedings of the National Academy of Sciences, USA 83:4680–4684
    [Google Scholar]
  38. Spalholz B. A., Yang Y.-C., Howley P. M. 1985; Transactivation of a bovine papillomavirus transcriptional regulatory element by the E2 gene product. Cell 42:183–191
    [Google Scholar]
  39. Tan S.-H., Gloss B., Bernard H.-U. 1992; During negative regulation of the human papillomavirus-16 E6 promoter, the viral E2 protein can displace Sp1 from a proximal promoter element. Nucleic Acids Research 20:251–256
    [Google Scholar]
  40. Ushikai M., Lace M. J., Yamakawa Y., Kono M., Anson J., Ishiji T., Parkkinen S., Wicker N., Valentine M.-E., Davidson I., Turek L. P., Haugen T. H. 1994; Trans-activation by the full-length E2 proteins of human papillomavirus type 16 and bovine papillomavirus type 1 in vitro and in vivo: cooperation with activation domains of cellular transcription factors. Journal of Virology 68:6655–6666
    [Google Scholar]
  41. Watanabe S., Kanda T., Yoshiike K. 1989; Human papillomavirus type 16 transformation of primary human embryonic fibroblasts requires expression of open reading frames E6 and E7. Journal of Virology 63:965–969
    [Google Scholar]
  42. Werness B. A., Levine A. J., Howley P. M. 1990; Association of human papillomavirus types 16 and 18 E6 proteins with p53. Science 248:76–79
    [Google Scholar]
  43. Wu X., Levine A. J. 1994; p53 and E2F-1 cooperate to mediate apoptosis. Proceedings of the National Academy of Sciences, USA 91:3602–3606
    [Google Scholar]
  44. Yee C., Krishnan-Hewlett I., Baker C. C., Schlegel R., Howley P. M. 1985; Presence and expression of human papillomavirus sequences in human cervical carcinoma cell lines. American Journal of Pathology 119:361–366
    [Google Scholar]
  45. zur Hausen H. 1991; Human papillomaviruses in the pathogenesis of anogenital cancer. Virology 184:9–13
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/jgv/10.1099/0022-1317-78-11-3009
Loading
/content/journal/jgv/10.1099/0022-1317-78-11-3009
Loading

Data & Media loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error