Progesterone Receptor-mediated Coordination Of Oocyte-oviduct Communication During Ovulation
Funder
National Health and Medical Research Council
Funding Amount
$86,128.00
Summary
Infertility affects 1 in 6 couples, often due to failed release of an egg from the ovary. The hormone progesterone is essential for this process. Our goal is to determine how progesterone signals the egg to ensure its correct release into the oviduct where fertilization may occur. To identify these signals, experiments will analyse ovary cells and eggs of mice, including mice that do not respond to progesterone. The results will provide much needed information about female reproductive health.
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
Neuroactive Steroids In The Fetal Brain: Role In The Regulation Of Behaviour And Protection Against Hypoxia
Funder
National Health and Medical Research Council
Funding Amount
$65,685.00
Summary
The major breakdown products of the steroid hormone, progesterone, form a group of hormones termed neuroactive steroids. These steroids have major effects on the activity of the brain and influence behaviour in adult subjects. Changes in the production of steroids by the steroid producing glands influences neurosteroid levels in the adult brain. This in tern may cause behavioural and mood changes in adults, leading to conditions such as premenstrual stress and postnatal depression. In fetal life ....The major breakdown products of the steroid hormone, progesterone, form a group of hormones termed neuroactive steroids. These steroids have major effects on the activity of the brain and influence behaviour in adult subjects. Changes in the production of steroids by the steroid producing glands influences neurosteroid levels in the adult brain. This in tern may cause behavioural and mood changes in adults, leading to conditions such as premenstrual stress and postnatal depression. In fetal life, the placenta releases large amounts of these neuroactive steroids and high concentrations of these steroid are found in the fetal circulation. We have shown that these steroids suppress the activity of the fetal brain, suppress arousal and maintain the fetus in a sleep-like state during pregnancy. In this proposal we investigate the hypothesis that cells in the fetal brain modify the neuroactive steroid environment within the brain so as to suppress fetal brain activity further during times of stress and, therefore, protect the brain from damage caused by excessive excitation. These mechanisms may prevent brain injury due to placental insufficiency during pregnancy and asphyxia during birth. The augmentation of these natural processes may form the bases for treatment strategies to provide additional protection for the fetal brain in high-risk pregnancies.Read moreRead less
Essential Protective Role Of Neuroactive Steroids In The Fetal And Neonatal Brain.
Funder
National Health and Medical Research Council
Funding Amount
$422,036.00
Summary
Brain injury may occur during complicated pregnancies and at birth, as well as in neonates following preterm labour, and is a major problem in neonatal medicine. The consequent nerve cell death leads to ongoing neurological impairment which represents a major cost to the individual and to the community. Neuroactive steroids are hormones related to the steroid hormone progesterone that have been shown to have a major influence on nerve cell activity and nervous transmission. While these hormones ....Brain injury may occur during complicated pregnancies and at birth, as well as in neonates following preterm labour, and is a major problem in neonatal medicine. The consequent nerve cell death leads to ongoing neurological impairment which represents a major cost to the individual and to the community. Neuroactive steroids are hormones related to the steroid hormone progesterone that have been shown to have a major influence on nerve cell activity and nervous transmission. While these hormones influence mood and behaviour in adult subjects, they have an even more important role in the fetus which is exposed to high levels of steroids from the placenta. The fetus is very sensitive to these neuroactive steroids and we have shown that they suppress the activity of the fetal brain so as to maintain the fetus in a sleep-like state during pregnancy. Periods of low oxygen supply (hypoxia) to the fetus may occur during pregnancy, as well as result from asphyxia at birth, and may lead to excessive excitation of nerve cells resulting in nerve cell death. Steroid-induced suppression reduces excitation of nerve cells and results in the fetus being resistant to excessive excitation. In this proposal we investigate the hypothesis that cells in the fetal brain modify the neuroactive steroid environment within the brain so as to suppress fetal brain activity further during times of hypoxic stress and, therefore, further protect the brain from damage caused by excessive excitation. These mechanisms may prevent brain injury due to placental insufficiency during pregnancy, asphyxia during birth and in premature babies. We will investigate whether the supplementation of these processes by administering neuroactive steroids may provide additional nerve protection during high-risk periods during pregnancy. These studies may identify a new as yet unexploited group of natural compounds which may improve infant health without adverse actions on the mother or baby.Read moreRead less
Follow-up Of Women On A Randomised Clinical Trial Of Adjuvant Docetaxel And Doxorubicin For Node Positive Breast Cancer.
Funder
National Health and Medical Research Council
Funding Amount
$113,250.00
Summary
This project is testing the use of a drug docetaxel in the post-operative (adjuvant) treatment of women with breast cancer and involved lymph nodes (N+). Until recently the drug doxorubicin was the most active chemotherapy drug for breast cancer, but more recently a new group of chemotherapy drugs called taxanes were identified. One taxane called docetaxel may be even more effective than doxoubicin. Using available treatments that include doxorubicin based chemotherapy, approximately half the wo ....This project is testing the use of a drug docetaxel in the post-operative (adjuvant) treatment of women with breast cancer and involved lymph nodes (N+). Until recently the drug doxorubicin was the most active chemotherapy drug for breast cancer, but more recently a new group of chemotherapy drugs called taxanes were identified. One taxane called docetaxel may be even more effective than doxoubicin. Using available treatments that include doxorubicin based chemotherapy, approximately half the women with N+ breast cancer experience recurrence of their cancer. It is therefore important to test whether the inclusion of docetaxel in adjuvant therapy can reduce relapses. If docetaxel is to be included, it is also important to test whether it is best to combine it with doxorubicin at the same time (which for safety reasons requires the doses of each drug to be reduced), versus giving them sequentially at full dose. Currently, docetaxel is not approved nor funded for use in early breast cancer in Australia. There are several international trials testing the inclusion of taxanes in the adjuvant therapy of breast cancer. However this trial stands out, because all the women in the trial receive chemotherapy of at least 6 months. In some other trials, testing the possible benefit of adding a taxane, women in the control treatment group (who were randomised not to receive the taxane) received only 3 months of treatment, which makes it difficult to distinguish between longer treatment or addition of the taxane drug. This trial has completed international recruitment of 2890 women who will be carefully followed for 10 years. Australian and New Zealand centers recruited 20% of the women in the trial. After the women have been followed-up for 5 years the results of this trial will be analysed, presented and published and should provide reliable evidence about the potential benefit of adding docetaxel into adjuvant chemotherapy.Read moreRead less
Clinical Trial Of Adjuvant Docetaxel And Doxorubicin For Node Positive Breast Cancer.
Funder
National Health and Medical Research Council
Funding Amount
$185,135.00
Summary
This project is investigating the optimal use of docetaxel and doxorubicin in the treatment of women with breast cancer and involved lymph nodes (N+). Every year 3000 women in Australia, and over 400,000 worldwide are newly diagnosed with N+ breast cancer. Using available treatments more than 60% of these (5 per day in Australia, 4,500 each week worldwide) will die from breast cancer. The efficacy of adjuvant chemotherapy in early breast cancer is well established by the international overview c ....This project is investigating the optimal use of docetaxel and doxorubicin in the treatment of women with breast cancer and involved lymph nodes (N+). Every year 3000 women in Australia, and over 400,000 worldwide are newly diagnosed with N+ breast cancer. Using available treatments more than 60% of these (5 per day in Australia, 4,500 each week worldwide) will die from breast cancer. The efficacy of adjuvant chemotherapy in early breast cancer is well established by the international overview conducted by the Early Breast Cancer Trialist's Collaborative Group (EBCTCG). They have demonstrated the efficacy of adjuvant chemotherapy on reducing mortality and recurrence rates, but current regimens are far from optimal. Docetaxel (Taxotere), a new agent, has effectiveness and manageable side effects in the treatment of advanced breast cancer patients, and can plausibly improve outcomes for patients with early N+ breast cancer by optimal integration into current adjuvant chemotherapy regimens. This clinical trial is designed to compare whether it is advantageous to use docetaxel and-or doxorubicin in combination or sequentially with other currently available chemotherapy drugs.Read moreRead less
Disrupted Neurosteroid Synthesis Mediates The Adverse Effects Of Prenatal Stress
Funder
National Health and Medical Research Council
Funding Amount
$695,973.00
Summary
Maternal anxiety and related stress in pregnancy influences the fetus causing developmental changes that adversely affect the offspring leading to behavioural problems in childhood. However, mechanisms which transfer maternal changes to the fetus are unclear. We propose that disruption of the fetal-placental neurosteroid system is a major link. We will identify the deficits in this system caused by maternal stress and then examine therapies to reverse these disruptions.