Role Of Betaglycan In Gonadal And Adrenal Tumourigenesis
Funder
National Health and Medical Research Council
Funding Amount
$487,500.00
Summary
TGF-beta and inhibin are related multifunctional growth factors which regulate a number of important cellular functions, including proliferation, differentiation, and survival. Betaglycan is a cell-surface protein that binds both inhibin and TGF-beta. Betaglycan appears to regulate the binding and availability of the TGF-betas and inhibins to their signaling receptors, and its presence on the cell surface increases the efficiency of TGF-beta and inhibin function. Deletion of the inhibin gene in ....TGF-beta and inhibin are related multifunctional growth factors which regulate a number of important cellular functions, including proliferation, differentiation, and survival. Betaglycan is a cell-surface protein that binds both inhibin and TGF-beta. Betaglycan appears to regulate the binding and availability of the TGF-betas and inhibins to their signaling receptors, and its presence on the cell surface increases the efficiency of TGF-beta and inhibin function. Deletion of the inhibin gene in mice produces tumours in the ovary, testis, and adrenal gland in 100% of the mice. In this current proposal, we will delete the betaglycan gene in the primary target tissues for inhibin (the anterior pituitary and gonads). The hypothesis we are testing is that the loss of a co-receptor for inhibin (i.e. betaglycan) results in a loss of cellular sensitivity to inhibin, thus resulting in altered growth characteristics which predispose the gonads and adrenals to cancer. We will examine these cells in culture and in living animals to determine whether our hypotheses are correct. We will also conduct a series of histological, biochemical, and biological experiments in order determine the underlying causes of any observed growth dysregulation. This work is expected to yield information relevant to the role of betaglycan in inhibin-TGFb-regulated processes in normal and cancerous growth, which may allow future design of therapies for cancer.Read moreRead less
Activin Type II Receptor Antagonists: Mechanism Of Action And Biological Applications
Funder
National Health and Medical Research Council
Funding Amount
$507,270.00
Summary
Activin is a member of the TGF- family of growth and differentiation factors. Over-expression in mice leads to muscle and liver wasting, scarring during wound healing, disturbances to the reproductive system and various endocrine disorders. Activin's biological activity is promoted by its binding in series to two receptors termed Type I and II. Previous studies by this investigator have shown that selective modification of activin's protein structure can result in activin forms (in this instance ....Activin is a member of the TGF- family of growth and differentiation factors. Over-expression in mice leads to muscle and liver wasting, scarring during wound healing, disturbances to the reproductive system and various endocrine disorders. Activin's biological activity is promoted by its binding in series to two receptors termed Type I and II. Previous studies by this investigator have shown that selective modification of activin's protein structure can result in activin forms (in this instance called activin-M108A) which bind to Type II receptors but fail to promote binding to the Type I receptor. This has led to the hypothesis that activin-M108A may compete for native activin binding to Type II receptors and thus prevent activin's recruitment of the Type I receptor with the consequence that activin's biological activity is inhibited. It is proposed to test this hypothesis by producing sufficient amounts of activin-M108A and testing its inhibitory effects in several mouse models of liver damage, muscular degeneration and ovarian and testicular disease. If activin-M108A, or related modified forms of activin, decrease the morbidity and mortality associated with these murine diseases, then we envisage that these activin type II receptor antagonists will also be beneficial for the treatment of related human conditions.Read moreRead less