Steroid hormones, such as oestrogen and cortisol, act in the body by binding a family of proteins (nuclear receptors) that bind directly to the DNA to regulate genes. The mechanisms underlying this process are complex and involve recruitment of additional molecules or coactivators to improve efficiency. Recently a novel coactivator was identified termed SRA, which remarkably is never made into protein in cells, rather exerting its effects as a RNA. We have identified a novel family of proteins t ....Steroid hormones, such as oestrogen and cortisol, act in the body by binding a family of proteins (nuclear receptors) that bind directly to the DNA to regulate genes. The mechanisms underlying this process are complex and involve recruitment of additional molecules or coactivators to improve efficiency. Recently a novel coactivator was identified termed SRA, which remarkably is never made into protein in cells, rather exerting its effects as a RNA. We have identified a novel family of proteins that bind to SRA in cancer cells, and may well play a critical role in regulating how SRA modulates genes. This project seeks to understand how this family interacts with SRA, the functional effects on breast cancer cells, and the detailed 3-dimensional structure of the family members coupled with SRA. This work will provide novel insight into how SRA regulates steroid hormone action, and may create new potential avenues for developing therapeutics in breast cancer.Read moreRead less
The Role Of Ghrelin And Growth Hormone Releasing Hormone In The Autocrine Regulation Of Prostate Cancer Cell Growth
Funder
National Health and Medical Research Council
Funding Amount
$240,990.00
Summary
Insulin-like growth factor-I (IGF-I) is an important growth factor with a major role in the growth and development of many normal and tumour cells. Its production is controlled by growth hormone (GH), released from the pituitary gland at the base of the brain. GH releasing hormone (GHRH), a hormone released from higher centres in the brain, regulates the production of GH itself and now it is recognised that a second pathway, the ghrelin-GH secretagogue receptor (GHS-R) axis is also important in ....Insulin-like growth factor-I (IGF-I) is an important growth factor with a major role in the growth and development of many normal and tumour cells. Its production is controlled by growth hormone (GH), released from the pituitary gland at the base of the brain. GH releasing hormone (GHRH), a hormone released from higher centres in the brain, regulates the production of GH itself and now it is recognised that a second pathway, the ghrelin-GH secretagogue receptor (GHS-R) axis is also important in regulating GH release. There is growing evidence that the GHRH-GH-IGF axis has a significant role in prostate cancer, but little is known about how this happens. We also have evidence that the ghrelin-GHS-R axis is involved in prostate cancer, as prostate cancer cell lines produce both ghrelin and the receptor through which it acts. Our preliminary studies show that ghrelin enhances cell growth in these cells. GHRH blocking agents (antagonists) are potential treatments for prostate cancer, as they slow the growth of prostate tumours. How they act is unclear, but they might interfere with a locally active GHRH pathway in the prostate. This study aims to explore the role of ghrelin and GHRH in prostate cancer. Since there is an increase in the use of GHRH, GH and-or IGF-I and potentially ghrelin for the treatment of a variety of medical conditions, including some in the aging male, the need for a fuller understanding of the role of this axis in prostate cancer is increasingly important. Such information will lead to a deeper understanding of the actions of ghrelin and GHRH and provide potential opportunities for design of new therapies for prostate and other GH-IGF-responsive tumours.Read moreRead less
Role Of The Nuclear Growth Hormone Receptor In Cell Proliferation And Function
Funder
National Health and Medical Research Council
Funding Amount
$477,750.00
Summary
In addition to final height, growth hormone regulates many tissues in the body, and through these, regulates metabolism, body composition, vitality and aspects of ageing. However, there is some evidence that GH can also promote cancer, notably colon and blood cell cancers. Our discovery of the receptor for growth hormone in the cell nucleus, notably in many cancers, has led us to investigate the role of the nuclear GH receptor. We have found that targeting this receptor to the nucleus allows the ....In addition to final height, growth hormone regulates many tissues in the body, and through these, regulates metabolism, body composition, vitality and aspects of ageing. However, there is some evidence that GH can also promote cancer, notably colon and blood cell cancers. Our discovery of the receptor for growth hormone in the cell nucleus, notably in many cancers, has led us to investigate the role of the nuclear GH receptor. We have found that targeting this receptor to the nucleus allows the cell to divide without the need for the normal factors which initiate cell division and survival. We have also found that a part of the GH receptor acts as a gene activator, and have identified some of the nuclear proteins which bind to the receptor and make this so. This proposal aims to establish the link between the nuclear GH receptor and cell division, both mechanistically, and in live animals. We also plan to establish if nuclear localizing the receptor artificially results in cancer formation. The outcome would provide an index of risk from current GH therapy, and could lead to a new cancer therapy.Read moreRead less
A Solution To The Parathyroid Gland Secretion Problem
Funder
National Health and Medical Research Council
Funding Amount
$508,003.00
Summary
Parathyroid hormone is the master hormone regulator of whole body calcium metabolism and a powerful new treatment for osteoporosis but the mechanism by which its natural secretion is controlled has never been solved. In this project we will apply new insights and advanced technical approaches to resolve this most fundamental question of calcium homeostasis, namely how parathyroid hormone secretion is controlled.
Focimatrix Regulation Of Sex Steroid Hormones In The Ovary
Funder
National Health and Medical Research Council
Funding Amount
$291,309.00
Summary
Sex steroid hormones (e.g. oestrogen and testosterone), are important to male and female health. In the ovarian follicle I identified a novel form of extracellular matrix (focimatrix) which develops in the ovary before the synthetic enzymes needed for sex steroids are present. Using evidence from other tissues, I developed ideas on how this matrix regulates the enzymes for hormone synthesis. I will examine a mechanism by which focimatrix could directly affect steroid hormone production.
Characterisation Of Erusiolin - A New Peptide Hormone
Funder
National Health and Medical Research Council
Funding Amount
$547,202.00
Summary
Obesity and type II diabetes are epidemic diseases in Australia. Gut-derived hormones are key mediators in these diseases, due to their role in regulating appetite and blood glucose levels. Therapeutic modulation of these hormones also provides significant benefits for patients. In this proposal, we will determine the metabolic functions, such as appetite control, for a previously uncharacterised hormone, which is an unexplored therapeutic target for obesity and diabetes.
Central Ghrelin Regulates Peripheral Glucose Metabolism
Funder
National Health and Medical Research Council
Funding Amount
$339,938.00
Summary
Recent evidence shows ghrelin is a key anti-starvation hormone that increases glucose production in order to maintain appropriate blood glucose concentrations. How ghrelin acts in the brain to control blood glucose concentrations remains unknown and will be the focus of this project. This project is relevant to disorders such as anorexia nervosa and will help us understand blood glucose regulation during conditions of food scarcity.
The steroid hormone aldosterone controls salt balance and hence, blood pressure. It also has been shown to have a significant role in cardiac failure. Although drugs that block the aldosterone receptor are beneficial in the treatment of heart failure, they are limited by potassium retention in the kidney. In order to develop tissue-specific blockers of the aldosterone receptor, it is necessary to identify mechanisms by which the receptor can be activated and/or blocked in these tissues.
Molecular Regulation Of CRH Gene Expression In The Human Placenta
Funder
National Health and Medical Research Council
Funding Amount
$70,285.00
Summary
Approximately 70% of infant death is a result of premature birth. Preterm delivery occurs in 6-10% of pregnancies, and there has been no reduction in this rate in the last 30 years. This is largely because we remain ignorant of how normal and preterm birth is controlled. Understanding the physiology of human pregnancy is a critical step in the development of ways to detect and prevent preterm birth. Our group has demonstrated a link between production of a hormone (corticotropin releasing hormon ....Approximately 70% of infant death is a result of premature birth. Preterm delivery occurs in 6-10% of pregnancies, and there has been no reduction in this rate in the last 30 years. This is largely because we remain ignorant of how normal and preterm birth is controlled. Understanding the physiology of human pregnancy is a critical step in the development of ways to detect and prevent preterm birth. Our group has demonstrated a link between production of a hormone (corticotropin releasing hormone, CRH) in the placenta and the length of time the baby is carried in the mother. In women who will deliver prematurely the rise in CRH production occurs earlier and more rapidly, while in women who deliver late the rise occurs more slowly. This work has led to the concept of a biological clock that determines the length of time the fetus will be carried by the mother before birth, and in which production of CRH in the placenta plays a central role. We have been studying how the CRH gene is controlled in placental cells. We have discovered some regions in the DNA of the CRH gene which have important roles in controlling how much CRH is made by the placenta. The experiments described in this project will determine the molecular mechanisms that control the production of CRH in the human placenta. This will be done by examining the DNA sequences involved in controlling the CRH gene and by identifying the proteins that actually perform the regulating functions that result in either increased or decreased amounts of CRH being produced by the placenta. This important information will help us better understand how normal and preterm birth is controlled, and from that knowledge new ways to detect and prevent premature birth can be developed.Read moreRead less