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E2F-1 overexpression sensitizes colorectal cancer cells to camptothecin

Abstract

Topoisomerase I inhibitors have been shown to have clinical activity against human colorectal cancer. Previous studies showed that the cytotoxicity of camptothecin, a topoisomerase I inhibitor, occurs mainly in the S -phase of the cell cycle and is protectable by aphidicolin, an inhibitor of replicative DNA polymerase in some camptothecin-sensitive colorectal cells. Transcription factor E2F-1 regulates the G1/S transition, and recent studies have shown that E2F-1 potentiated the cytotoxicity of some cell-cycle-related drugs. Therefore, the present study was designed to investigate the effect of adenovirus-mediated E2F-1 gene transfer on chemosensitivity of colorectal cancer to camptothecin, in vitro and in vivo. Two human colorectal cancer cells, SW620 (mutant p53) and RKO (wild-type p53), were treated with camptothecin, alone or in combination with adenoviral vectors expressing β-galactosidase (Ad-LacZ), or E2F-1 (Ad-E2F-1). E2F-1 overexpression was confirmed by Western blot analysis. Ad-E2F-1 gene transfer at low doses (less than the LD20 dose) markedly increased the sensitivity of human colorectal cancer cells to camptothecin in vitro, which is because of induction of apoptosis. Aphidicolin did not have any protective effect on the Ad-E2F-1/camptothecin-mediated cytotoxicity. The level of topoisomerase I expression was not affected by combination treatment as well, suggesting that DNA replication and topoisomerase I activity may not account for the molecular mechanism of cell killing in response to Ad-E2F-1/camptothecin treatment. Fas and Fas ligand expression were not altered by treatment with camptothecin and/or Ad-E2F-1. Moreover, combination of camptothecin and Ad-E2F-1 has an additive antitumor effect in an in vivo nude mouse xenograft model. When combined with camptothecin, E2F-1 adenovirus therapy resulted in a 95.7% decrease in tumor size compared to control groups (P<.05). These results suggest a chemosensitization strategy that may have clinical utility in human colorectal cancer.

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References

  1. Macdonald JS, Astrow AB . Adjuvant therapy of colon cancer. Semin Oncol. 2001;28:30–40.

    Article  CAS  Google Scholar 

  2. Grivicich I, Mans DR, Peters GJ, et al. Irinotecan and oxaliplatin: an overview of the novel chemotherapeutic options for the treatment of advanced colorectal cancer. Braz J Med Biol Res. 2001;34:1087–1103.

    Article  CAS  Google Scholar 

  3. Saltz L . Irinotecan-based combinations for the adjuvant treatment of stage III colon cancer. Oncology. 2000;14:47–50.

    CAS  PubMed  Google Scholar 

  4. Liu JR, Opipari AW, Tan L, et al. Dysfunctional apoptosome activation in ovarian cancer: implications for chemoresistance. Cancer Res. 2002;62:924–931.

    CAS  PubMed  Google Scholar 

  5. Schmitt CA, Lowe SW . Apoptosis and chemoresistance in transgenic cancer models. J Mol Med. 2002;80:137–146.

    Article  CAS  Google Scholar 

  6. Poulain L, Lincet H, Duigou F, et al. Acquisition of chemoresistance in a human ovarian carcinoma cell is linked to a defect in cell cycle control. Int J Cancer. 1998;78:454–463.

    Article  CAS  Google Scholar 

  7. Lutzker SG, Levine AJ . Apoptosis and cancer chemotherapy. Cancer Treat Res. 1996;87:345–356.

    Article  CAS  Google Scholar 

  8. Slichenmyer WJ, Rowinsky EK, Donehower RC, et al. The current status of camptothecin analogues as antitumor agents. J Natl Cancer Inst. 1993;85:271–291.

    Article  CAS  Google Scholar 

  9. Shimada Y, Yoshino M, Wakui A, et al. Phase II study of CPT-11, a new camptothecin derivative, in metastatic colorectal cancer. CPT-11 Gastrointestinal Cancer Study Group. J Clin Oncol. 1993;11:909–913.

    Article  CAS  Google Scholar 

  10. Gupta M, Abdel-Megeed M, Hoki Y, et al. Eukaryotic DNA topoisomerases mediated DNA cleavage induced by a new inhibitor: NSC 665517. Mol Pharmacol. 1995;48:658–665.

    CAS  PubMed  Google Scholar 

  11. Liu LF, Desai SD, Li TK, et al Mechanism of action of camptothecin. Ann NY Acad Sci. 2000;922:1–10.

    Article  CAS  Google Scholar 

  12. Avemann K, Knippers R, Koller T, et al. Camptothecin, a specific inhibitor of type I DNA topoisomerase, induces DNA breakage at replication forks. Mol Cell Biol. 1988;8:3026–3034.

    Article  CAS  Google Scholar 

  13. Horwitz SB, Horwitz MS . Effects of camptothecin on the breakage and repair of DNA during the cell cycle. Cancer Res. 1973;33:2834–2836.

    CAS  PubMed  Google Scholar 

  14. Pommier Y, Leteurtre F, Fesen MR, et al. Cellular determinants of sensitivity and resistance to DNA topoisomerase inhibitors. Cancer Invest. 1994;12:530–542.

    Article  CAS  Google Scholar 

  15. Hsiang YH, Lihou MG, Liu LF . Arrest of replication forks by drug-stabilized topoisomerase I-DNA cleavable complexes as a mechanism of cell killing by camptothecin. Cancer Res. 1989;49(18):5077–5082.

    CAS  PubMed  Google Scholar 

  16. Goldwasser F, Bae I, Valenti M, et al. Topoisomerase I-related parameters and camptothecin activity in the colon carcinoma cell lines from the National Cancer Institute anticancer screen. Can Res. 1995;55:2116–2121.

    CAS  Google Scholar 

  17. Sugimoto Y, Tsukahara S, Oh-hara T, et al. Decreased expression of DNA topoisomerase I in camptothecin-resistant tumor cell lines as determined by a monoclonal antibody. Cancer Res. 1990;50:6925–6930.

    CAS  PubMed  Google Scholar 

  18. Benedetti P, Fiorani P, Capuani L, et al. Camptothecin resistance from a single mutation changing glycine 363 of human DNA topoisomerase I to cysteine. Cancer Res. 1993; 53:4343–4348.

    CAS  PubMed  Google Scholar 

  19. Rubin E, Pantazis P, Bharti A, et al. Identification of a mutant human topoisomerase I with intact catalytic activity and resistance to 9-nitro-camptothecin. J Biol Chem. 1994; 269:2433–2439.

    CAS  PubMed  Google Scholar 

  20. Girling R, Bandara LR, Ormondroyd E, et al. A new component of transcription factor DRTF1/E2F. Nature. 1993; 362:83–87.

    Article  CAS  Google Scholar 

  21. De Gregori J, Kowalik T, Nevins JR . Cellular targets for activation by the E2F-1 transcription factor include DNA synthesis and G1/S-regulatory genes. Mol Cell Biol. 1995;5: 4215–4224.

    Article  Google Scholar 

  22. Hunt KK, Deng J, Liu TJ, et al. Adenovirus-mediated overexpresion of the transcription factor E2F-1 induces apoptosis in human breast and ovarian carcinoma cell lines and does not require p53. Cancer Res. 1997;57:4722–4726.

    CAS  PubMed  Google Scholar 

  23. Fueyo J, Gomez-Manzano C, Yung WK, et al. Overexpression of E2F-1 in glioma triggers apoptosis and suppresses tumor growth in vitro and in vivo. Nat Med. 1998;4:685–690.

    Article  CAS  Google Scholar 

  24. Dong YB, Yang HL, Elliott MJ, et al. Adenovirus-mediated E2F-1 gene transfer efficiently induces apoptosis in melanoma cells. Cancer 1999;86:2021–2033.

    Article  CAS  Google Scholar 

  25. Yang HL, Dong YB, Elliott MJ, et al. Caspase activation and changes in Bcl-2 family member protein expression associated with E2F-1-mediated apoptosis in human esophageal cancer cells. Clin Cancer Res. 2000;6:1579–1589.

    CAS  PubMed  Google Scholar 

  26. Yang HL, Dong YB, Elliott MJ, et al. Adenovirus-mediated E2F-1 gene transfer inhibits MDM2 expression and efficiently induces apoptosis in mdm2-overexpressing tumor cells. Clin Cancer Res. 1999;5:2242–2250.

    CAS  PubMed  Google Scholar 

  27. Dong YB, Yang HL, Elliott MJ, et al. Adenovirus-mediated E2F-1 gene transfer sensitizes melanoma cells to apoptosis induced by topoisomerase II inhibitors. Cancer Res. 2002;62:1776–1783.

    CAS  PubMed  Google Scholar 

  28. Yang HL, Dong YB, Elliott MJ, et al. Additive effect of adenovirus-mediated E2F-1 gene transfer and topoisomerase II inhibitors on apoptosis in human osteosarcoma cells. Cancer Gene Ther. 2001;8:241–251.

    Article  CAS  Google Scholar 

  29. Meng RD, Phillips P, EL-Deiry WS . P53-independent increase in E2F-1 expression enhances the cytotoxic effects of etoposide and of adriamyicn. Int J Oncol. 1999;14:5–14.

    CAS  PubMed  Google Scholar 

  30. Banerjee D, Schnieders B, Fu JZ, et al. Role of E2F-1 in chemosensitivity. Cancer Res. 1998;58:4292–4296.

    CAS  PubMed  Google Scholar 

  31. Nip J, Strom DK, Lee BE, et al. E2F-1 cooperates with topoisomerase II inhibition and DNA damage to selectively augment p53-independent apoptosis. Mol Cell Biol. 1997; 17:1049–1056.

    Article  CAS  Google Scholar 

  32. O'Connor DJ, Lu X . Stress signals induce transcriptionally inactive E2F-1 independently of p53 and RB. Oncogene. 2000;19:2369–2376.

    Article  CAS  Google Scholar 

  33. Elliott MJ, Dong YB, Yang HL, et al. E2F-1 up-regulates c-Myc and p14(ARF) and induces apoptosis in colon cancer cells. Clin Cancer Res. 2001;7:3590–3597.

    CAS  PubMed  Google Scholar 

  34. Goldwasser F, Shimizu T, Jackman J, et al. Correlations between S and G2 arrest and the cytotoxicity of camptothecin in human colon carcinoma cells. Cancer Res. 1996;56:4430–4437.

    CAS  PubMed  Google Scholar 

  35. Jaks V, Joers A, Kristjuhan A, Maimets T . p53 protein accumulation in addition to the transactivation activity is required for p53-dependent cell cycle arrest after treatment of cells with camptothecin. Oncogene. 2001;20:1212–1219.

    Article  CAS  Google Scholar 

  36. Motwani M, Jung C, Sirotnak FM, et al. Augmentation of apoptosis and tumor regression by flavopiridol in the presence of CPT-11 in Hct116 colon cancer monolayers and xenografts. Clin Cancer Res. 2001;7:4209–4219.

    CAS  PubMed  Google Scholar 

  37. Waldman T, Zhang Y, Dillehay L, et al. Cell-cycle arrest versus cell death in cancer therapy. Na Med. 1997;3:1034–1036.

    Article  CAS  Google Scholar 

  38. Lamb JR, Friend SH . Which guesstimate is the best guesstimate? Predicting chemotherapeutic outcomes. Nat Med. 1997;3:962–963.

    Article  CAS  Google Scholar 

  39. Wu X, Levine AJ . p53 and E2F-1 cooperate to mediate apoptosis. Proc Natl Acad Sci USA. 1994;91:3602–3606.

    Article  CAS  Google Scholar 

  40. Kowalik TF, DeGregori J, Schwarz JK, et al. E2F-1 overexpression in quiescent fibroblasts leads to induction of cellular DNA synthesis and apoptosis. J Virol. 1995;69:2491–2500.

    CAS  PubMed  PubMed Central  Google Scholar 

  41. Hiebert SW, Packham G, Strom DK, et al. E2F-1: DP-1 induces p53 and overrides survival factors to trigger apoptosis. Mol Cell Biol. 1995;15:6864–6874.

    Article  CAS  Google Scholar 

  42. Holmberg S, Helin K, Sehested M, et al. E2F-1-induced p53-independent apoptosis in transgenic mice. Oncogene. 1998;17:143–156.

    Article  CAS  Google Scholar 

  43. Kuerbitz SJ, Plunkett BS, Walsh WV, et al. Wild-type p53 is a cell cycle checkpoint determinant following irradiation. Proc Natl Acad Sci USA. 1992;89:7491–7495.

    Article  CAS  Google Scholar 

  44. Shao RG, Cao CX, Nieves-Neira W, et al. Activation of the Fas pathway independently of Fas ligand during apoptosis induced by camptothecin in p53 mutant human colon carcinoma cells. Oncogene. 2001;20:1852–1859.

    Article  CAS  Google Scholar 

  45. Giovanella BC, Hinz HR, Kozielski AJ, et al. Complete growth inhibition of human cancer xenografts in nude mice by treatment with 20-(S)-camptothecin. Cancer Res. 1991;51:3052–3055.

    CAS  PubMed  Google Scholar 

  46. Jordan-Sciutto KL, Hall DJ . A mutant E2F-1 transcription factor that affects the phenotype of NIH3T3 fibroblasts inefficiency associates with cyclin A-cdk2. Biochem Cell Bio. 1998;76:37–44.

    Article  CAS  Google Scholar 

  47. Chen AY, Liu LF . DNA tpoisomerases: essential enzymes and lethal targets. Annu Rev Pharmacol Toxicol. 1994;34:191–218.

    Article  CAS  Google Scholar 

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Acknowledgements

We thank Dr TJ Liu for providing the Ad-E2F-1 vector and Dr Brent French for providing the Ad5CMVLacZ vector. We thank Sherri Matthews for expert assistance with manuscript preparation. This work was supported by Grant 96-55 from the American Cancer Society, Grant 96-46 from the Alliant Community Trust Fund, The Mary and Mason Rudd Foundation Award, and the Center for Advanced Surgical Technologies (CAST) at Norton Hospital.

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Correspondence to Kelly M McMasters.

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Financial support: Supported by American Cancer Society Award 96-55, Alliant Community Trust Fund Award 96-46, the Center for Advanced Surgical Technologies (CAST) of Norton Hospital.

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Dong, Y., Yang, H. & McMasters, K. E2F-1 overexpression sensitizes colorectal cancer cells to camptothecin. Cancer Gene Ther 10, 168–178 (2003). https://doi.org/10.1038/sj.cgt.7700565

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