Suppression of mammary-derived growth inhibitor gene expression by growth hormone and insulin-like growth factor I.

  • Authors:
    • H Huynh
    • W Beamer
  • View Affiliations

  • Published online on: September 1, 1998     https://doi.org/10.3892/ijo.13.3.577
  • Pages: 577-659
Metrics: Total Views: 0 (Spandidos Publications: | PMC Statistics: )
Total PDF Downloads: 0 (Spandidos Publications: | PMC Statistics: )


Abstract

When introduced into MCF-7 breast cancer cells, the mammary-derived growth inhibitor (MDGI) gene causes them to revert to a more normal behavior. MDGI is silenced in several human breast cancer cell lines and in most breast tumors. Antiestrogens (tamoxifen and ICI 182780), which are commonly used in breast cancer treatment, stabilize MDGI mRNA. Insulin-like growth factors (IGFs) are well characterized mitogenic and anti-apoptotic factors involved in mammary gland physiology. We demonstrate that MDGI gene expression was inversely correlated with IGF-II gene expression. In the mammary gland of growth hormone releasing hormone receptor mutant (Ghrhrlit/Ghrhrlit) mice, the MDGI gene was overexpressed. Administration of IGF-I or GH to Ghrhrlit/Ghrhrlit mice suppressed MDGI mRNA levels in a dose-dependent manner. Administration of the somatostatin analogue octreotide to pituitary intact rats in a manner previously shown to acutely suppress the GH/IGF-I axis, up-regulated mammary gland MDGI expression in a dose-dependent fashion. The data document a previously unrecognized role of IGF-I in the regulation of the tumor suppressor gene MDGI, in the mammary gland, and may aid in the design of new physiological approaches to breast cancer prevention and/or treatment.

Related Articles

Journal Cover

Sep 1998
Volume 13 Issue 3

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

Sign up for eToc alerts

Recommend to Library

Copy and paste a formatted citation
x
Spandidos Publications style
Huynh H and Huynh H: Suppression of mammary-derived growth inhibitor gene expression by growth hormone and insulin-like growth factor I.. Int J Oncol 13: 577-659, 1998
APA
Huynh, H., & Huynh, H. (1998). Suppression of mammary-derived growth inhibitor gene expression by growth hormone and insulin-like growth factor I.. International Journal of Oncology, 13, 577-659. https://doi.org/10.3892/ijo.13.3.577
MLA
Huynh, H., Beamer, W."Suppression of mammary-derived growth inhibitor gene expression by growth hormone and insulin-like growth factor I.". International Journal of Oncology 13.3 (1998): 577-659.
Chicago
Huynh, H., Beamer, W."Suppression of mammary-derived growth inhibitor gene expression by growth hormone and insulin-like growth factor I.". International Journal of Oncology 13, no. 3 (1998): 577-659. https://doi.org/10.3892/ijo.13.3.577