Upregulation of E2F transcription factors in chemically induced mouse skin tumors.

  • Authors:
    • S Balasubramanian
    • N Ahmad
    • H Mukhtar
  • View Affiliations

  • Published online on: August 1, 1999     https://doi.org/10.3892/ijo.15.2.387
  • Pages: 387-477
Metrics: Total Views: 0 (Spandidos Publications: | PMC Statistics: )
Total PDF Downloads: 0 (Spandidos Publications: | PMC Statistics: )


Abstract

E2F family of transcription factors plays an important role in cell cycle regulation, oncogenesis and differentiation. E2Fs are a family of heterodimeric transcription factors composed of E2F-like and DP-like subunits. They regulate expression of specific genes controlling cellular proliferation by binding to specific sequences within the promoter regions of these target genes and affecting their transcription in a cell cycle dependent manner. Recent studies have suggested an essential role of Rb/E2F pathway in the passage of cells through the G1 phase of the cell cycle. To better understand the role of these transcription factors in epithelial tumorigenesis, we compared the expression of various proteins involved in the Rb/E2F pathway in epidermis and 7,12-dimethylbenz(a)anthracene (DMBA)-initiated and 12-O-tetradecanoylphorbol-13-acetate (TPA) promoted papillomas on SENCAR mouse skin. Western blot analysis data showed 3.0- to 7.6-fold upregulation of E2F-1, E2F-2, E2F-3, E2F-4 and E2F-5 in tumors compared to normal epidermis. In tumors, the protein expression of DP-1 did not show significant change whereas that of DP-2 showed a 2.2-fold increase. Compared to normal epidermis, a significant upregulation of pRb (6.3-fold) and p107 (13-fold) was also observed in tumors. The protein expression of p130 was not detectable either in normal epidermis or in tumors. These data suggest that the overexpression of E2F proteins may be involved in the G1-S phase dysregulation that occurs during mouse skin tumorigenesis.

Related Articles

Journal Cover

August 1999
Volume 15 Issue 2

Print ISSN: 1019-6439
Online ISSN:1791-2423

Sign up for eToc alerts

Recommend to Library

Copy and paste a formatted citation
APA
Balasubramanian, S., Ahmad, N., & Mukhtar, H. (1999). Upregulation of E2F transcription factors in chemically induced mouse skin tumors.. International Journal of Oncology, 15, 387-477. https://doi.org/10.3892/ijo.15.2.387
MLA
Balasubramanian, S., Ahmad, N., Mukhtar, H."Upregulation of E2F transcription factors in chemically induced mouse skin tumors.". International Journal of Oncology 15.2 (1999): 387-477.
Chicago
Balasubramanian, S., Ahmad, N., Mukhtar, H."Upregulation of E2F transcription factors in chemically induced mouse skin tumors.". International Journal of Oncology 15, no. 2 (1999): 387-477. https://doi.org/10.3892/ijo.15.2.387