IGF and Insulin Action in the Mammary Gland: Lessons from Transgenic and Knockout Models
- Resource Type
- Academic Journal
- Authors
- Hadsell, Darryl L.; Bonnette, Sharon G.
- Source
- Journal of Mammary Gland Biology & Neoplasia. Jan 01, 2000 5(1):19-30
- Subject
- Language
- English
- ISSN
- 1083-3021
Transgenic and knockout mice have become valuable experimental systems with which to study specific molecular events within the mammary gland of an intact animal. These models have provided a wealth of information about the effects of a number of oncogenes and growth factors. This review focuses on results obtained from the application of transgenic and knockout models to determine the roles of insulin and insulin-like growth factors (IGF) in the regulation of mammary gland development, lactation and tumorigenesis. Transgenic models which overexpress IGF-I or -II display specific alterations in mammary gland development and an increased incidence of mammary tumors. Analysis of mammary gland development in knockout mice which are deficient in IGF-I or the IGF-I receptor supports the conclusion that the IGF system is important for normal mammary gland development. This review discusses these observations in detail and attempts to fit them into a larger picture of IGF and insulin action in the mammary gland.