Hormone Transport By Alpha-2-Macroglobulin: Novel Roles In Regulating Hormone Activity
Funder
National Health and Medical Research Council
Funding Amount
$602,857.00
Summary
Alpha-2-macroglobulin is a large protein in the blood known to bind and transport numerous hormones in the circulation. Our previous studies published in BLOOD (2009) and JBC (2013) have discovered an important role for this molecule in the transport and regulation of a peptide hormone. The studies proposed in this application have important implications for understanding new roles of alpha-2-macroglobulin in hormone binding and regulating the activity of hormones in disease states.
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
Impact Of Progesterone Receptor Subnuclear Localisation On Progesterone Action In Endocrine Target Cells
Funder
National Health and Medical Research Council
Funding Amount
$459,514.00
Summary
Breast cancer affects 10,000 Australian women annually and is a major cause of cancer death. The hormone progesterone, which is produced by the ovaries in women, is responsible for some aspects of the development of the normal breast in women and is also implicated in the development and response of breast and endometrial cancers. In normal cells progesterone acts via a specific protein (or receptor) in the nucleus, and we have shown that this protein accumulates into foci when it is active. We ....Breast cancer affects 10,000 Australian women annually and is a major cause of cancer death. The hormone progesterone, which is produced by the ovaries in women, is responsible for some aspects of the development of the normal breast in women and is also implicated in the development and response of breast and endometrial cancers. In normal cells progesterone acts via a specific protein (or receptor) in the nucleus, and we have shown that this protein accumulates into foci when it is active. We have noticed that in cancers, this accumulation is disrupted, and this is a bad sign for the cancer. As breast cancer develops, it causes many dramatic changes in the structure of cells of the breast, and particularly in the nucleus, which carries the genetic information that programs cancer cell behaviour. The nucleus normally is highly organised into compartments, which carry out different functions of the cell, such as duplication of the DNA, repair of DNA after damage, and switching on and off of particular genes important to the function of the cell. This organisation is altered dramatically in cancer cells, and it seems that this altered organisation is responsible for altered function. In this project we aim to work out what makes the receptor for progesterone form foci, how these foci are involved in the action of progesterone, and how the changed structure of the nucleus changes this process. This project will link the structure of the cell nucleus with the ability of progesterone to switch on or off particular genes, and this will provide the first signposts of how changes seen in cancer cell nuclei are reflected in changed hormonal signalling. Healthy women are regularly exposed to progestins in oral contraceptives and hormone replacement therapy. The known increased risk of breast cancer as a result of exposure to progestins creates an imperative to understand how progesterone may have aberrant effects. This project will address this important health issue.Read moreRead less
Alpha-2-Macroglobulin And The Transport And Uptake Of The Hormone, Hepcidin
Funder
National Health and Medical Research Council
Funding Amount
$533,541.00
Summary
Hepcidin is a peptide hormone that is a major regulator of iron metabolism. It has been suggested that hepcidin is free in the blood. However, we recently identified that hepcidin binds with alpha-2-macroglobulin (a2-M) in the plasma and this increases the efficacy of this peptide. The demonstration that a2-M plays a role in hepcidin biology will lead to a better understanding of hepcidin physiology, the development of methods for its measurement and improved treatment of iron related diseases.
Biomarkers For The Treatment And Prognosis Of Sight-threatening Diabetic Retinopathy
Funder
National Health and Medical Research Council
Funding Amount
$598,305.00
Summary
Diabetic retinopathy (DR) is a highly specific vascular complication of both type 1 and type 2 diabetes, with prevalence strongly related to the duration of diabetes. Clinic biomarkers of DR have become the basis for preventive medicine. In this project, we aim to evaluate possible biomarkers in both Chinese and Australian diabetic populations at different stages of DR. We will also investigate pathological mechanisms and novel drugs to treat DR in animal models.
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
Novel Endocrine Approaches To Diagnosis & Treatment Of Men With Prostate Cancer
Funder
National Health and Medical Research Council
Funding Amount
$926,980.00
Summary
Most men are diagnosed with localised prostate cancer, others have advanced disease. Vision: Identify how tumours are insignificant vs aggressive (Aim 1.1 & 1.2). Predict which tumours will progress to incurable disease (Aim 1.3) and how to target them (Aim 1.4). Discover how each patient tumour is different (Aim 2.1) and pre-clinically test new therapies (Aim 2.2). Outcomes: practice changing discoveries that identify novel therapeutic targets & biomarkers improving diagnosis and treatment.
Regulation Of Growth Hormone Action By Oestrogen And Selective Oestrogen Receptor Modulators
Funder
National Health and Medical Research Council
Funding Amount
$474,750.00
Summary
Growth hormone (GH) is essential for body growth and development. In adult life, it plays a key role in regulating the ratio of body fat to muscle, thus influencing health. Disruption of GH action decreases muscle mass and increases body fat. These changes lead to reduced muscle strength and fitness, and increase the risk of diabetes, hypertension and cardiovascular mortality. Our laboratory has reported that oestrogens taken orally blunt GH action and cause unfavourable changes in body fat and ....Growth hormone (GH) is essential for body growth and development. In adult life, it plays a key role in regulating the ratio of body fat to muscle, thus influencing health. Disruption of GH action decreases muscle mass and increases body fat. These changes lead to reduced muscle strength and fitness, and increase the risk of diabetes, hypertension and cardiovascular mortality. Our laboratory has reported that oestrogens taken orally blunt GH action and cause unfavourable changes in body fat and muscle. How this happens is not known. As oral oestrogens are widely used in our society, it is important to understand the basis of their impact on GH action. SERMs, or selective oestrogen receptor modulators, are a group of drugs used in the treatment of breast cancer and osteoporosis. These substances mimic oestrogen action in some tissues, and block oestrogen action in others. Whether SERMs interfere with GH action as oestrogens do have not been studied, but such knowledge would have therapeutic significance because of their widespread and long-term use. GH action is mediated by a protein, called the GH receptor, located on the surface of target tissues. We propose that oestrogens and SERMs alter the production and function of this protein to control GH action. Thereby, this project is designed to test, in cultured cells of human origin, how oestrogens and SERMs modulate abundance of the GH receptor and its ability to mediate GH action. This work is anticipated to gain novel insights into the interaction of GH with oestrogens and SERMs. This information may also be useful for the design of new drugs devoid of adverse effects on GH action, and hence would have potentially significant implications in women s health and disease.Read moreRead less