Genetic Analysis Of Cell Death Pathways, Drug Resistance And Oncogenic Co-operativity In IL-3 Dependent Cell Lines
Funder
National Health and Medical Research Council
Funding Amount
$445,270.00
Summary
The ultimate fate of most of our cells is to die by committing suicide, because they are no longer required, are no longer functioning, or are potentially harmful. This normal physiological process is termed apoptosis . Inappropriate apoptosis can contribute to cell loss following heart attacks, stroke or neurodegenerative diseases, such as Alzheimer s or Parkinson s disease. Conversely, when cell death fails to occur, abnormal cells can accumulate and lead to cancer. In addition, because drugs ....The ultimate fate of most of our cells is to die by committing suicide, because they are no longer required, are no longer functioning, or are potentially harmful. This normal physiological process is termed apoptosis . Inappropriate apoptosis can contribute to cell loss following heart attacks, stroke or neurodegenerative diseases, such as Alzheimer s or Parkinson s disease. Conversely, when cell death fails to occur, abnormal cells can accumulate and lead to cancer. In addition, because drugs that are used to treat cancer may exert their effect by inducing apoptosis, a failure of this suicide response may cause resistance to chemotherapy. The genes of the apoptosis pathway function either to promote or inhibit cell death. We have found that some genes in the apoptosis pathway allow apoptosis to proceed rapidly, but do not decide the fate of the cell. Other genes are required for a cell to commit to die. If these genes are mutated then apoptosis does not occur and a functional cell may survive. The distinction between cells that decide fate and those that do not is crucial because it is only the genes that decide cell fate that can act as cancer genes, and are valid targets for therapy. We use a model in which apoptosis is caused by removal of a growth factor, using cell lines derived from mice that lack particular genes in the cell death pathway. These cells proliferate normally in the presence of growth factor, and allow us to determine the role of the genes when growth factor is withdrawn. Because these cells are sensitive to chemotherapeutic drugs, we can also determine the contribution these genes make to cancer drug sensitivity. Using this system, we have discovered that Puma, a gene known to be required for apoptosis in response to radiation, is also a critical activator of apoptosis following growth factor withdrawal. We will determine the manner in which Puma is regulated by growth factors, as well as identify and characterise other key components.Read moreRead less
Immunological Studies Of Adjutant Induced Arthritis
Funder
National Health and Medical Research Council
Funding Amount
$412,104.00
Summary
This project stems from our interest in rheumatoid arthritis and a number of other forms of arthritis that affect many joints in a symmetrical fashion (the polyarthritides). In most instances, there is evidence that the diseases are caused by an attack on the joint lining (the synovium) by cells of the immune system. Rheumatoid arthriis is the most common and often the most severe of the polyarthritides. Neither the triggering event nor the target of the attack by the immune system is understood ....This project stems from our interest in rheumatoid arthritis and a number of other forms of arthritis that affect many joints in a symmetrical fashion (the polyarthritides). In most instances, there is evidence that the diseases are caused by an attack on the joint lining (the synovium) by cells of the immune system. Rheumatoid arthriis is the most common and often the most severe of the polyarthritides. Neither the triggering event nor the target of the attack by the immune system is understood and as a result, there are no specific preventative measures against the disease or specific therapies for the established disease. There is, however, strong evidence that the cells involved in the attack on the synovium are orchestrated by a white blood cell called the T lymphocyte. T lymphocytes cannot operate alone but require a second cell, the dendritic cell, to present the target in a special way which can be recognised and responded to by the T lymphocyte. The T cell and the dendritic cell are the two central aspects of this project. We will use an animal model of polyarthritis to allow access to these cells during the earliest phases of the disease, a silent period not recognisable in the earliest stages of rheumatoid arthritis. T lymphocytes from animals with experimental polyarthritis will be used as indicators in the search for the target of the disease process and dendritic cells from affected joints will be used as a natural source of that target. By the production of highly specific T lymphocytes (members of clones), we hope to identify the target molecules of the disease process. This information should lead ultimately to the identification of the triggering stimulus (and thence prevention) and to the development of highly specific therapies designed to treat the established disease.Read moreRead less
The Role Of Oxidative Stress In The Patho-aetiology Of Prion Disorders Using Infected Cell Culture And Animal Models
Funder
National Health and Medical Research Council
Funding Amount
$112,014.00
Summary
The transmissible spongiform encephalopathies (TSE; also known as prion diseases) are a biologically unique and fascinating group of invariably fatal diseases which primarily affect the brains of both humans and animals. In humans, sporadic Creutzfeldt-Jakob disease (CJD) is the most common form, while in animals it is the recent epidemic of bovine spongiform encephalopathy (mad cow disease), and its probable transmission to humans as new variant CJD, which has drawn so much attention to this gr ....The transmissible spongiform encephalopathies (TSE; also known as prion diseases) are a biologically unique and fascinating group of invariably fatal diseases which primarily affect the brains of both humans and animals. In humans, sporadic Creutzfeldt-Jakob disease (CJD) is the most common form, while in animals it is the recent epidemic of bovine spongiform encephalopathy (mad cow disease), and its probable transmission to humans as new variant CJD, which has drawn so much attention to this group of disorders. The preponderance of scientific evidence now supports the belief that infectivity in TSEs relates predominantly (probably exclusively) to a protein (called the prion protein; PrP) which is normally found on the cell surface of a number of types of brain cells, including neurons. Transmissibility, and hence infectivity, is more correctly associated with a malfolded version of PrP into an abnormal shape which gives the mutant protein significantly different biological and biochemical properties, including relative resistance to breakdown by enzymes that metabolise proteins (proteases) and enhanced tendency to aggregate. However, the precise steps involved in this transformation to the abnormal infectious form of PrP are not known. Similarly, our understanding of how different folding and accumulation of this protein brings about disease is not clear. Nevertheless, as with other neurological diseases (eg Alzheimer's disease) which are a consequence of unexplained spontaneous premature degeneration of parts of the brain (neurodegenerative diseases), oxidative stress is increasingly believed to play a role. Oxidative stress is a generic term used to describe the enhanced production within a cell of small, very harmful, oxygen containing molecules which under normal circumstances can be successfully detoxified. This project involves a detailed study of the role of oxidative stress in the causation of prion diseases using both mouse and cell culture models.Read moreRead less
A Mechanotransduction Apparatus To Coordinate Epithelial Collective Cell Migration.
Funder
National Health and Medical Research Council
Funding Amount
$994,596.00
Summary
Epithelial cells migrate as physically coherent collective groups, which is necessary for normal development and is disrupted as cancers progress to become invasive and spread. Collective migration requires communication so that the behaviour of individual cells is properly coordinated. In this project we investigate how the transmission of physical force between cells allows them to communicate; and test how its disruption contributes to cancer invasion.
Investigating The Consequences Of Dysregulated Lipogenesis In Cancer
Funder
National Health and Medical Research Council
Funding Amount
$600,647.00
Summary
Reprogramming of cellular metabolism is a hallmark of cancer. As such, there has been growing interest in developing strategies to exploit metabolism for therapeutic gain. Our ability to do this is dependent on a thorough understanding of the mechanisms by which dysregulation of cellular metabolism contributes to tumour progression. In this project, we seek to the investigate the fundamental mechanisms by which aberrant activation of lipid metabolism contributes to the tumourigenic process.
Function Of The Lysophospholipid Receptor Family In Neuronal Stem Cells And Their Progenitors.
Funder
National Health and Medical Research Council
Funding Amount
$380,723.00
Summary
Stem cells have the potential to give rise to a vast array of differentiated cells. Neuronal stem cells (NSC) can differentiate into progenitor cells which can themselves differentiate into cells of the nervous system: neurons and macroglial cells (astrocytes, oligodendrocytes, Schwann cells). This in turn can assist in the treatment of degenerative diseases such as multiple sclerosis, Parkinson's disease, motoneuron desease etc. Our project aims to study the effects on NSC and their progenitor ....Stem cells have the potential to give rise to a vast array of differentiated cells. Neuronal stem cells (NSC) can differentiate into progenitor cells which can themselves differentiate into cells of the nervous system: neurons and macroglial cells (astrocytes, oligodendrocytes, Schwann cells). This in turn can assist in the treatment of degenerative diseases such as multiple sclerosis, Parkinson's disease, motoneuron desease etc. Our project aims to study the effects on NSC and their progenitor cells of the lysophospholipids lysophosphatidic acid (LPA) and sphingosine-1-phosphate (S1P), bioactive molecules known to play an essential role in the nervous system during development and inflammation. Our project aims to understand the mechanisms of action of these molecules in NSC maintenance, proliferation, differentiation and migration. By understanding how these molecules are able to regulate NSC biology will provide new avenues in the development of tools necessary for stem cell therapy.Read moreRead less
Regulation Of The Drosophila C-Myc Homologue In Stem Cell Growth And Division.
Funder
National Health and Medical Research Council
Funding Amount
$613,397.00
Summary
The mechanisms controlling stem cell growth and division require elucidation if we are to use stem cells in regenerative medicine and find cancer treatments. Due to experimental limitations such mechanisms are largely unknown in humans. We aim to use the vinegar fly as a model system to understand the importance of microenvironment to cancer gene control in stem cells. We will identify the secreted signals, from the neighbouring cells, required to control cancer initiation in stem cells.