Abstract
Background: It has been demonstrated that 2-Methoxyestradiol (2-ME), one of the estrogen metabolites, induces apoptosis in many different tumor cell lines. In the present study, the effects of 2-ME on human cervical cancer HeLaS3 cells and on normal cervical epithelial cells were evaluated. Materials and Methods: Acridine orange staining, DNA fragmentation arrays and flow cytometry were used to measure the apoptosis and cell cycle progression. In addition, the effect of 2-ME on expression of iNOS was measured by Western blot. Results: 2-ME inhibited the growth of HeLaS3 cells. This growth inhibition was accompanied by apoptosis and G2/M cell cycle arrest. 2-ME increased the expression of iNOS in parallel with apoptosis. Moreover, apoptosis was prevented by the iNOS inhibitor 1400W. 2-ME treatment resulted in a slight increase of the G2/M population, but no apoptosis, in normal cervical epithelial cells. There was no synergetic effect between E2 and 2-ME. Conclusion: 2-ME induced apoptosis via the iNOS pathway and caused G2/M cell cycle arrest in human cervical cancer HeLaS3 cells, but showed only slight effects on normal cervical epithelial cells. These data suggest that 2-ME might be an adjuvant agent in the treatment of cervical cancer.
Footnotes
- Received August 1, 2003.
- Accepted December 28, 2003.
- Copyright© 2004 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved