Molecular Analysis Of Myelodysplasia In The Nup98HoxD13 Mouse Model
Funder
National Health and Medical Research Council
Funding Amount
$351,502.00
Summary
Myelodysplastic syndrome is a preleukemic condition which is poorly understood and occuring at an increasing frequency. Unfortunately no targeted therapy exists. Two features of the disease are abnormal gene expression and abnormal cell death. We have a uniquely accurate model of this disease, and we plan to use it to investigate these two phenomena which will lead to greater understanding of the disease and new molecular targets for therapeutic agents to be developed and tested in our model.
Regulated Targeting Of Cell Death Effectors To And From Mitochondria.
Funder
National Health and Medical Research Council
Funding Amount
$302,764.00
Summary
The protein components of human cells travel to their appropriate intracellular homes by means of the targeting signals they carry. It now seems that a short, but important, list of key regulatory proteins are victims of protein hijacking: these proteins provide critical functions within a particular sub-cellular compartment, but are initially prevented from finding their way to this intracellular home. Only in response to specific physiological signals are these proteins released to find the si ....The protein components of human cells travel to their appropriate intracellular homes by means of the targeting signals they carry. It now seems that a short, but important, list of key regulatory proteins are victims of protein hijacking: these proteins provide critical functions within a particular sub-cellular compartment, but are initially prevented from finding their way to this intracellular home. Only in response to specific physiological signals are these proteins released to find the site at which they act. Human cells carry a molecular death-wish. A specific set of genes encode factors (proteins) that would ensure cellular suicide, or programmed cell death, but this program is only turned on in response to precise environmental signals. Because of the potentially deadly nature of these proteins, several of them are subject to protein hijacking thereby neutralizing their ability to promote cell death. These cell death factors are of great interest, and understanding their location and relocation within cells is crucial, as they represent targets for novel chemotherapies. Selectively triggering a cellular suicide has been proposed as a sensitive means to preventing the uncontrolled cell proliferation at the heart of many cancers. We are studying a set of key regulatory proteins to determine how and when they find their way to the intracellular homes and how this targeting effects their function in programmed cell death.Read moreRead less
Understanding The Mechanism Of Action And Pathophysiological Function Of The NOR1 And Nur77 Orphan Nuclear Receptors
Funder
National Health and Medical Research Council
Funding Amount
$269,250.00
Summary
Nuclear hormone receptors (NRs) function as ligand-hormone activated transcription factors that regulate gene expression involved in reproduction, development and metabolism. Dysfunctional hormonal signalling, and inappropriate NR function results in reproductive disorders, inflammation, cancer, diabetes, and cardiovascular disease. The significance of NRs in disease is underscored by the range of pharmacopoeia developed for the treatment of NR associated disorders. Orphan NRs belong to the supe ....Nuclear hormone receptors (NRs) function as ligand-hormone activated transcription factors that regulate gene expression involved in reproduction, development and metabolism. Dysfunctional hormonal signalling, and inappropriate NR function results in reproductive disorders, inflammation, cancer, diabetes, and cardiovascular disease. The significance of NRs in disease is underscored by the range of pharmacopoeia developed for the treatment of NR associated disorders. Orphan NRs belong to the superfamily on the basis of their sequence identity, however, the endogenous signaling molecules which bind to these proteins are unknown. The orphan NRs Nur77, NURR1, and NOR1, functions as stress response genes which are induced by a wide range of physiological stimuli Furthermore, the NR4A subgroup of receptors has been implicated in carcinogenesis, neurological disorders; inflammation, diabetes and atherogenesis. The objective of this proposal is to examine the molecular mechanisms that control the regulation of gene expression by the orphan nuclear receptors, Nur77 and NOR-1. Furthermore, we will investigate the pathophysiological function of NOR-1 and Nur77 in muscle. Nur77 and NOR-1 are expressed in skeletal muscle. This major mass tissue accounts for ~40% of total body weight and, is a major site of glucose and fat metabolism. Consequently, this peripheral tissue plays a significant role in insulin sensitivity, and the blood lipid profile. Furthermore, a collaboration with industry has identified NOR-1 as an insulin responsive gene in muscle, which becomes hyper-sensitive to insulin induction in diabetic patients. Additionally, we have exciting evidence that the anti-neoplastic purine anti-metabolite, 6-mercaptopurine activates the NR4A subgroup. Nur77 and NOR-1 represent an exciting challenge, and unlocking the molecular mechanisms that NOR-1-dependent transcription provides the opportunity for identifying novel signaling pathways, and therapeutics.Read moreRead less
Antagonists Of P38 MAPK As Therapeutics For Acute Lymphoblastic Leukemia.
Funder
National Health and Medical Research Council
Funding Amount
$521,961.00
Summary
New therapies are needed to treat patients with leukemia. Moving leukemic cells into the blood reduces their growth and increases the effects of chemotherapy. Currently we cannot move leukemic cells into the blood without moving normal blood forming cells, making them more sensitive to chemotherapy. We have identified a drug that only affects leukemic cell movement. This study will examine the potential of this drug to treat leukemia.
Characterization Of 72 And 52 KDa Inositol Polyphosphate 5-phosphatases: Role In Vesicular Trafficking And Cell Death
Funder
National Health and Medical Research Council
Funding Amount
$408,055.00
Summary
Cells respond to the external environment, stress, hormones and grow th factors by generating messages inside the cell that send a signal to the nucleus that stimulates cell growth. One such signalling network is that produced by membrane lipids known as phosphoinositides. Enzymes or kinases that modify these membrane lipids in particular an enzyme known as the PI 3-kinase generate potent signalling molecules that regulate cell growth. It has been shown by many studies that signals generated by ....Cells respond to the external environment, stress, hormones and grow th factors by generating messages inside the cell that send a signal to the nucleus that stimulates cell growth. One such signalling network is that produced by membrane lipids known as phosphoinositides. Enzymes or kinases that modify these membrane lipids in particular an enzyme known as the PI 3-kinase generate potent signalling molecules that regulate cell growth. It has been shown by many studies that signals generated by the PI 3-kinase are amplified in certain human cancers. Inherited cancer syndromes have been described in which the cell has lost the ability to switch off these lipid messenger molecules. The current project aims to investigate two recently identified enzymes called 5-phosphases that have the ability to terminate PI 3-kinase membrane signals. Both these enzymes were isolated and characterized by the host laboratory and it is predicted they will play distinct roles in the cell. The 72 kDa 5-phosphatase is predicted to regulate protein and vesicular trafficking to the surface of cell. This proposal aims to investigate if the 72 kDa 5-phosphatase can regulate the intracellular sorting of new proteins within the cell. We have also noted the 72 kDa 5-phosphatase may play a role in the development of the nervous system in particular the ability of nerves to send branches out and differentiate. This proposal will investigate this hypothesis. The second enzyme that we have isolated is a 52 kDa 5-phosphatase. This enzyme is present in many cells. We have compelling evidence that the enzyme forms a complex with a recently decribed protein called SODD that stops cells from dying in response to inappropropirate signals. We predict the 52 kDa 5-phosphatase may function to prevent prolonged cell survival as is observed in cancer. We will investigate if this enzyme regulates the cell death pathway and if increased or decreased levels of the 52 kDa 5-phosphatase alter cell survivalRead moreRead less
Cancer is the result of multiple genetic errors, involving both the overactivity of growth-stimulating oncogenes and the loss of tumour suppressor genes. The identification of the genes in both of these categories is important if we are to understand and intervene in the disease. Tumour suppressors are the more difficult to identify, precisely because they are lost in cancer cells. Normally the task is extremely time consuming, tedious and expensive. We have developed a system which will provide ....Cancer is the result of multiple genetic errors, involving both the overactivity of growth-stimulating oncogenes and the loss of tumour suppressor genes. The identification of the genes in both of these categories is important if we are to understand and intervene in the disease. Tumour suppressors are the more difficult to identify, precisely because they are lost in cancer cells. Normally the task is extremely time consuming, tedious and expensive. We have developed a system which will provide a short-cut to the cloning of one such gene. We have started with the mouse version, which is lost in leukemic cells. We have mapped the gene to within a very small chromosomal region, and we have identified a biological effect which correlates with loss of the gene. Our next step is to combine these two approaches to clone the gene. Because these genes are always highly conserved between species, we will be able to quickly clone the corresponding human gene, the loss of which is very likely to be important in cancer of various types.Read moreRead less
Acute Lymphoblastic Leukemia And The Bone Marrow Microenvironment
Funder
National Health and Medical Research Council
Funding Amount
$420,872.00
Summary
This research aims to identify new drugs for the treatment of childhood and adult acute lymphoblastic leukemia (ALL). We have identified drugs that interfere with interactions between the bone marrow and leukemic cells and hypothesise that these will increase the potency of currently used chemotherapy. We will test these agents in animal models of human leukemia. By analysing the effects of these new drugs we will also understand how we can further improve treatments.