Insulin signal transduction in normal cells and its role in carcinogenesis.

Convincing epidemiological evidence exists for a causal relationship between increased risk of cancer development and progression and type 2 diabetes mellitus as well as obesity. Though the underlying mechanisms remain elusive, in light of the well-described mitogenic actions of insulin, hyperinsulinaemia in the presence of insulin resistance is probably a key factor. In this short review, an overview over the insulin signalling cascade is given paying special attention to the mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PI 3-K)/mammalian target of rapamycin (mTOR) pathways which are involved in protein synthesis and cell growth. (c) J. A. Barth Verlag in Georg Thieme Verlag KG Stuttgart, New York.