Adrenocortical cancers have a poor prognosis. It is essential that patients with adrenocortical cancers be diagnosed early and accurately to enable the initiation of appropriate treatment. Current methods do not reliably differentiate benign adrenal tumours from adrenocortical cancers. The aim of my project is to identify molecular markers which can accurately distinguish benign adrenal tumours from adrenocortical cancers, allowing accurate diagnosis and institution of optimal therapy.
Role Of Liver Receptor Homologue-1 (LRH-1) In Male Germ Cells
Funder
National Health and Medical Research Council
Funding Amount
$224,250.00
Summary
Historically the steroid sex hormones - oestrogens and androgens - have been regarded as female- and male- specific sex hormones, respectively. Oestrogens are produced by the ovary and regulate female-specific processes such as ovulation and development of female sexual characteristics, whereas androgens are produced by the testis and regulate male-specific functions. However it is now clear that the distinction between oestrogen and androgen is not a sharp one. For example, we now know that oes ....Historically the steroid sex hormones - oestrogens and androgens - have been regarded as female- and male- specific sex hormones, respectively. Oestrogens are produced by the ovary and regulate female-specific processes such as ovulation and development of female sexual characteristics, whereas androgens are produced by the testis and regulate male-specific functions. However it is now clear that the distinction between oestrogen and androgen is not a sharp one. For example, we now know that oestrogens are produced within the testis and play a very important role in male fertility. Human males patients who are unable to synthesise oestrogens are infertile. Similarly, mice that cannot produce oestrogens are also infertile, due to a defect in sperm production. Oestrogens are therefore critical for normal male fertility, and reduced oestrogen production within the testis may be a significant cause of infertility which would be easily treatable in the clinic. The protein LRH-1 regulates oestrogen production in other tissues. This proposal aims to identify the role of LRH-1 in testicular oestrogen production by identifiying the genes regulated by LRH-1 and the proteins that interact with it in the testis. We also aim to study the structure of these proteins in infertile men. These studies will define new genes associated with male infertility and may lead to the development of more effective treatments for this common condition.Read moreRead less
An Examination Of The Contribution Of Visceral Adiposity To Insulin Resistance In Humans.
Funder
National Health and Medical Research Council
Funding Amount
$335,800.00
Summary
The worldwide epidemic of Type 2 diabetes is related to major nutritional and activity changes interacting with a genetic predisposition. The two key defects in Type 2 diabetes are a reduced response to insulin (insulin resistance) and relative failure of insulin production. Insulin resistance is the earliest defect and is closely associated with cardiovascular risk. Obesity generates insulin resistance, but intraabdominal (visceral) fat has particular importance. Visceral fat cells are differen ....The worldwide epidemic of Type 2 diabetes is related to major nutritional and activity changes interacting with a genetic predisposition. The two key defects in Type 2 diabetes are a reduced response to insulin (insulin resistance) and relative failure of insulin production. Insulin resistance is the earliest defect and is closely associated with cardiovascular risk. Obesity generates insulin resistance, but intraabdominal (visceral) fat has particular importance. Visceral fat cells are different to other fat cells; they are very metabolically active and 'spill out' fatty acids indiscriminately contributing to insulin resistance in liver and muscle; they also produce hormones which may modify the action of insulin. We will study people undergoing abdominal surgery. Participants will be (1) normal weight and sensitive to insulin, (2) abdominally overweight and insulin resistant, (3) insulin resistant with Type 2 diabetes. We will document abdominal fat, circulating lipid and hormone levels and insulin action. At surgery fat biopsies will be obtained from (a) inside the abdominal cavity, (b) the fat layer under the abdominal skin and (c) fat in the buttock. The activity of a large number of genes in the fat tissue will be assessed in 8 subjects using DNA array (4 each from Groups 1 and 2). Then a small number of genes will be selected on the basis of different activity in visceral fat from buttock fat, and between insulin sensitive and insulin resistant people. The activity of these genes will be determined in all subjects in the 3 groups. We anticipate identifying a few (perhaps 3) genes whose activity is closely associated with insulin resistance and will examine their capability to block insulin action in a series of animal and cellular studies. These studies should identify specific mechanisms by which visceral fat creates insulin resistance. This would be an important step towards prevention and improved medication for Type 2 diabetes.Read moreRead less
Progesterone Signalling In Normal And Malignant Breast Relies On Chromosomal Positioning Of Progesterone Receptor
Funder
National Health and Medical Research Council
Funding Amount
$569,346.00
Summary
The cell nucleus carries genetic information that directs cell function. The nucleus is organised into compartments, which are altered in breast cancer, leading to altered function. The ovarian hormone progesterone acts via a receptor, which clumps into foci in the nucleus when active. In cancers, this clumping is disrupted. In this project we will work out how these foci control cell function, and how this leads to the specific functions of progesterone in normal breast and breast cancers.
Growth hormone is responsible for normal postnatal growth, is an important metabolic regulator in starvation, and has many useful therapeutic applications, including forms of cardiac insufficiency, Crohns disease and, it is thought, amelioration of ageing. The means whereby GH brings about these changes are not known, although we do know a considerable amount about how the individual domains within the GH receptor signal. What we do not know is which genes are regulated by GH in these processes, ....Growth hormone is responsible for normal postnatal growth, is an important metabolic regulator in starvation, and has many useful therapeutic applications, including forms of cardiac insufficiency, Crohns disease and, it is thought, amelioration of ageing. The means whereby GH brings about these changes are not known, although we do know a considerable amount about how the individual domains within the GH receptor signal. What we do not know is which genes are regulated by GH in these processes, and how this will change the state of the cell. We propose here to use the new technique of gene arrays to uncover the programs, or groups of genes, which GH regulates to change important cellular processes. When used in conjunction with cells expressing GH receptor mutants which are unable to signal to defined pathways, we will be able to know which functional families genes are regulated, and how they are regulated. This information will enable us to know how GH regulates cell growth and metabolism, and therfore to understand what goes wrong when GH or its mediator, IGF-1 , are abnormal. We can also use this information to validate small molecules designed to mimic GH through activating its receptor, to be certain that they are acting in the same way as GH.Read moreRead less
Significance And Mechanisms Of Relative Progesterone Receptor Isoform Expression In Normal And Malignant Target Tissues
Funder
National Health and Medical Research Council
Funding Amount
$737,248.00
Summary
The ovarian hormone progesterone has a pivotal role in normal female physiology, in the uterus and ovary; in the mammary gland and in the brain. Human progesterone receptor, through which progesterone exerts its physiological effects, is expressed as two receptor proteins (PRB and PRA). These are identical except that PRA is shorter than PRB and present knowledge supports a role for both proteins in normal physiology. PR is also expressed in breast cancers, where one of its roles may be to inhib ....The ovarian hormone progesterone has a pivotal role in normal female physiology, in the uterus and ovary; in the mammary gland and in the brain. Human progesterone receptor, through which progesterone exerts its physiological effects, is expressed as two receptor proteins (PRB and PRA). These are identical except that PRA is shorter than PRB and present knowledge supports a role for both proteins in normal physiology. PR is also expressed in breast cancers, where one of its roles may be to inhibit oestrogen action and thereby limit tumour growth. A tumour which lacks PR would lack this capacity and this may be clinically associated with poorer prognosis. We have shown that primary tumours lacking PR are more likely to progress to secondary sites and this may provide support for this possibility. In addition, we have shown that over-expression of one PR isoform in breast cancers can be as biologically significant as lack of PR: tumours expressing predominantly one isoform were associated with poorer prognosis features.This project is aimed at investigating how PRA and PRB exert their effects on the range of progesterone targets in normal and malignant tissues. We will do this by determining whether PR isoforms are located in the same nuclear site in cells expressing one versus cells expressing both PR isoforms, to explore whether the proteins act separately in target cells. We will then ask whether the PR activity is different if only one isoform (PRA or PRB) is expressed versus both PRA and PRB. Another major issue which will be explored is the way in which the relative levels of PRA and PRB are controlled, and whether this is altered in breast cancers. Finally, we will explore the clinical significance of PR isoform expression. If achieved, the aims of this project will delineate the individual and combined action of - THIS FIELD WAS OVER 2000 CHARS, TEXT WAS REMOVED TO LODGE THE APPLICATION. A COPY OF THE ORIGINAL APPLICATION IS AVAILABLE FROM ARCHIVE-HARDCOPYRead moreRead less
Endocrine And Molecular Regulation Of Placental CRH Expression
Funder
National Health and Medical Research Council
Funding Amount
$466,980.00
Summary
Approximately 70% of infant death is associated with premature birth. Preterm birth occurs in 6-10% of pregnancies, and there has been no reduction in the rates of premature birth in the last 30 years. This is largely because we remain ignorant of how normal and abnormal 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 (corticotr ....Approximately 70% of infant death is associated with premature birth. Preterm birth occurs in 6-10% of pregnancies, and there has been no reduction in the rates of premature birth in the last 30 years. This is largely because we remain ignorant of how normal and abnormal 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 (corticotrophin releasing hormone, CRH) in the placenta and the length of time the baby is carried in the mother. In women who will deliver prematurely a rise in CRH occurs earlier in the pregnancy and more rapidly, while in women who deliver late the rise occurs more slowly. This work has given rise 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 research project will determine the molecular mechanisms that control the production of CRH in the human placenta. This will be done in two ways: (1) by examining the DNA sequences involved in controlling expression of the CRH gene and (2) 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 abnormal birth is controlled, and from that knowledge new ways to detect and prevent premature birth can be invented.Read moreRead less
Characterisation Of The Molecular Mechanisms Mediating Aldosterone-induced Epithelial Electrolyte Transport
Funder
National Health and Medical Research Council
Funding Amount
$488,386.00
Summary
The steroid hormone aldosterone regulates blood pressure by controlling sodium retention. The importance of this role is underlined by the fact that all known mongenetic hypertensive conditions involve aldosterone or sodium retention. Aldosterone mediates this effect by activating an intracellular receptor protein that in turn switches on specific genes. This study seeks to identify the genes that are switched on (or off) by aldosterone and to characterise the region of the gene that interacts w ....The steroid hormone aldosterone regulates blood pressure by controlling sodium retention. The importance of this role is underlined by the fact that all known mongenetic hypertensive conditions involve aldosterone or sodium retention. Aldosterone mediates this effect by activating an intracellular receptor protein that in turn switches on specific genes. This study seeks to identify the genes that are switched on (or off) by aldosterone and to characterise the region of the gene that interacts with the receptor. Both cell and gene specific factors are thought to be important in defining the nature of this interaction; these factors will also be sought. This information will enhance our understanding of the basic biology of sodium transport in the colon and the kidney which in turn will clarify the role of aldosterone in high blood pressure, cardiac disease and perhaps even stress.Read moreRead less
Investigation Of COX-2 Regulation Of Bone Turnover And Mechanically Induced Bone Formation By Genetic Overexpression.
Funder
National Health and Medical Research Council
Funding Amount
$440,750.00
Summary
This project is important because it uses novel experimental models to advance our knowledge of prostaglandin biology in normal and pathological bone remodelling, and the response of the skeleton to increased physical activity. We expect that a genetic modification in mice to increase the normal production of key prostaglandin enzymes, cyclooxygenase-2 (COX-2), in bone cells will increase the number of cells that remove bone (osteoclasts), and increase bone loss and the rate of bone turnover whe ....This project is important because it uses novel experimental models to advance our knowledge of prostaglandin biology in normal and pathological bone remodelling, and the response of the skeleton to increased physical activity. We expect that a genetic modification in mice to increase the normal production of key prostaglandin enzymes, cyclooxygenase-2 (COX-2), in bone cells will increase the number of cells that remove bone (osteoclasts), and increase bone loss and the rate of bone turnover when compared to normal mice. We believe this will occur via the effect of prostaglandins on expression of genes that control osteoclast formation. This will be tested by examining the structure of the skeleton, and the expression of certain genes, in transgenic mice at different ages from 2-8 months. These effects may be exacerbated in conditions of increased bone turnover, such as postmenopausal bone loss. This will be tested by examining the bone structure and gene expression in adult mice following removal of their ovaries. Due to the role of COX-2 in adaptation of bone to mechanical loading, we also expect the load-bearing skeleton to be more sensitive to increased weight-bearing activity. We will investigate this hypothesis by applying mechanical loads to the tibiae of mice in a controlled manner and then analysing the bone structure. Knowledge of specific pathways by which bone formation can be stimulated is important for developing novel approaches to induction and augmentation of osteogenesis in skeletal diseases associated with ageing or disability, or for maintenance of new bone around implants. The discovery that COX-2 is a key enzyme in mechanotransduction and osteoclastogenesis in bone, and a pharmacological target for modulating inflammation, has considerable clinical significance. Exploiting this knowledge requires precise knowledge of the role of this enzyme in bone remodelling and adaptation and our experiments will contribute significantly to that knowledgeRead moreRead less
Characterisation Of Alterations In The Androgen Signalling Axis That Contribute To Treatment Failure In Prostate Cancer
Funder
National Health and Medical Research Council
Funding Amount
$559,157.00
Summary
Prostate cancer is a major health problem in Western Countries including Australia, where it is the most common newly diagnosed invasive cancer and the second leading cause of cancer deaths in men. Although there have been improvements in the diagnosis of prostate cancer, many men are still diagnosed with disease that already has or will spread to other sites such as bone (ie metastatic disease). For those men with metastatic disease, reduction in testicular androgens by surgical or medical mean ....Prostate cancer is a major health problem in Western Countries including Australia, where it is the most common newly diagnosed invasive cancer and the second leading cause of cancer deaths in men. Although there have been improvements in the diagnosis of prostate cancer, many men are still diagnosed with disease that already has or will spread to other sites such as bone (ie metastatic disease). For those men with metastatic disease, reduction in testicular androgens by surgical or medical means (ie androgen ablation) is the only effective treatment option available. While androgen ablation is initially effective, treatment failure is common, resulting in a very poor overall survival rate. Evidence from our studies and others suggest that, the androgen receptor, which mediates the growth regulatory effects of androgens is often defective in prostate tumour cells. These altered or mutant receptors are activated inappropriately by other sex hormones such as estradiol and even agents used in the treatment of prostate cancer whereas the normal receptor is activated only by testicular androgens. This mechanism may explain why treatment fails in a subset of men with advanced prostate cancer. The major objective of our current studies is to define how these mutant androgen receptors cause treatment failure and facilitate prostate tumour growth. In addition, the current studies will evaluate a novel approach to treatment of prostate cancer which, based upon our preliminary results, has the potential to be effective even if alterations are present in the androgen receptor. The current studies therefore will provide a better understanding of factors controlling the growth of prostate tumours, and develop improved treatment approaches for advanced prostate cancer.Read moreRead less