Developing Novel Molecules To Down-Regulate Src Family Tyrosine Kinases
Funder
National Health and Medical Research Council
Funding Amount
$201,261.00
Summary
Leukaemia and cancer cells have altered biochemical properties resulting in their high rate of growth compared to normal cells. One of the common biochemical characteristics of cancer-leukaemia cells is augmented activity levels of enzymes called tyrosine kinases. A major group of tyrosine kinase involved in several cancer-leukaemia types is called the Src family of tyrosine kinases. One member of this family called Lyn has been our focus of study for several years, investigating the signalling ....Leukaemia and cancer cells have altered biochemical properties resulting in their high rate of growth compared to normal cells. One of the common biochemical characteristics of cancer-leukaemia cells is augmented activity levels of enzymes called tyrosine kinases. A major group of tyrosine kinase involved in several cancer-leukaemia types is called the Src family of tyrosine kinases. One member of this family called Lyn has been our focus of study for several years, investigating the signalling pathways that it is involved in. This molecule has also been implicated in several specific leukaemia (Chronic Myeloid Leukaemia and Acute Myeloid Leukaemia) as well as cancer (Prostate, Colon, Breast) in recent years. We have identified a novel mechanism of down-regulation of this enzyme mediated by an adapter molecule called Cbp, which recruits the Lyn inactivating molecules Csk-Ctk as well as SOCS-1; together they inhibit the activity of Lyn and degrade the enzyme. Using our knowledge of the essential interaction elements of Cbp we will design and test various mini-Cbp molecules for their ability to inactivate and degrade Lyn in leukemic and cancer cells. These molecules may allow us to develop novel therapeutics capable of inactivating-degrading specific tyrosine kinases in cancer and leukaemia.Read moreRead less
Mature red cells develop from hemopoietic stem cells in the adult bone marrow. The production of red blood cells is primarily controlled by the hormone erythropoietin (Epo). Previously we had identified that the protein Lyn must be present inside primitive red blood cells for Epo to stimulate them to become mature functional cells. We will determine the role of several molecules that interact with Lyn including Cbp, Liar and LACM, towards apects of red blood cell development.
Leukaemia-cancer cells have altered biochemical properties resulting in their high rate of growth compared to normal cells. One of these is augmented activity of enzymes called tyrosine kinases including members of the Src family. One called Lyn has been implicated in several leukaemias as well as cancer. We have identified a novel mechanism of down-regulating this family of enzymes mediated by small proteins. These may allow us to develop novel therapeutics for cancer-leukaemia treatment.
Erythroid Molecular Cascades Involving The Tyrosine Kinase Lyn
Funder
National Health and Medical Research Council
Funding Amount
$496,500.00
Summary
Mature red and white cells develope from hemopoietic stem cells in the adult bone marrow. The production of red blood cells is primarily controlled by the hormone erythropoietin (Epo). The availability of this hormone in a recombinant form has aided in the treatment of numerous forms of anaemia resulting from kidney failure, malignancies, and AIDS. Previously we had identified that the protein Lyn must be present inside primitive red blood cells for Epo to stimulate them to become mature functio ....Mature red and white cells develope from hemopoietic stem cells in the adult bone marrow. The production of red blood cells is primarily controlled by the hormone erythropoietin (Epo). The availability of this hormone in a recombinant form has aided in the treatment of numerous forms of anaemia resulting from kidney failure, malignancies, and AIDS. Previously we had identified that the protein Lyn must be present inside primitive red blood cells for Epo to stimulate them to become mature functional cells. Recently, we have demonstrated that mice lacking the Lyn gene develope major problems with their red blood cells. We have identified several molecules which interact with Lyn in red blood cells. We have shown that a molecule called Cbp is important for Epo function in individual red blood cells and now we plan to investigate its function in whole animals. We have shown that a new molecule called Arp is important for red blood cell development. This protein moves in and out of the nucleus (where DNA is stored) and may be important in the regulation of genes needed for red blood cells. The third gene (AFAPbeta) is also novel and is closely related to another called AFAP-110, which can exert effects on the structure of a cell. Since red blood cells have to shrink considerably during their development, the role of AFAPbeta on red blood cell structure will also be investigated. From these experiments we should develop a much better understanding of how the production of red blood cells is controlled and how diseases of red blood cells (such as anaemia) occur.Read moreRead less
Signalling Networks As Targets For Antibody Therapy In Glioma.
Funder
National Health and Medical Research Council
Funding Amount
$526,683.00
Summary
Antibodies are a major component of the bodies immune system that bind (i.e. stick) to foreign substances such as viruses. Once bound, these antibodies can activate other parts of the immune system, which help destroy the foreign substance. Analogous to the situation above, a number of institutions are testing antibodies that bind to cancer cells, in order to determine if they are able to destroy these cells. It is also possible to generate antibodies that bind to receptors on the surface of can ....Antibodies are a major component of the bodies immune system that bind (i.e. stick) to foreign substances such as viruses. Once bound, these antibodies can activate other parts of the immune system, which help destroy the foreign substance. Analogous to the situation above, a number of institutions are testing antibodies that bind to cancer cells, in order to determine if they are able to destroy these cells. It is also possible to generate antibodies that bind to receptors on the surface of cancer cells and block their function. If you target a receptor critical to the growth or survival of a cancer cell in this way, then swtiching-off this signal may inhibit tumor growth. In this proposal we plan to test a panel antibodies that recognize receptors important to the growth of brain cancer. Two of these antibodies have been generated and the other two will be made as part of this proposal. A key aspect of this proposal will be testing these antibodies in combination to determine how many receptors need to be targeted in order to get complete tumor regressions in animal models. Overall this work will help us identify new therapeutic strategies for the treatment of brain cancer. Finally, we will also analyze the way different receptors interact together in brain cancer cells.Read moreRead less
Throughout our lives cells must die and be replenished. One way multicellular organisms remove unwanted cells is through a process called programmed cell death. This process eliminates redundant, damaged or infected cells by a program of cell suicide. We are studying the underlying molecular mechanisms of this cell suicide in order to design new pharmaceuticals to treat illnesses caused by a disruption in programmed cell death. The fine balance between living and dying cells must be maintained a ....Throughout our lives cells must die and be replenished. One way multicellular organisms remove unwanted cells is through a process called programmed cell death. This process eliminates redundant, damaged or infected cells by a program of cell suicide. We are studying the underlying molecular mechanisms of this cell suicide in order to design new pharmaceuticals to treat illnesses caused by a disruption in programmed cell death. The fine balance between living and dying cells must be maintained and if this balance is lost then disease may result. A reduced level of cell death may result in cancers while too many dying can contribute to degenerative diseases such as Alzheimer's disease and stroke. Currently many of these diseases do not have effective treatments. We will determine the three-dimensional structures of key proteins involved in programmed cell death and use this information to design drugs that can interfere with the molecular processes involved in signalling cell death. Such drugs may prove useful new therapies in a wide range of diseases caused by a breakdown in the biochemical paths to cell death.Read moreRead less
Identification Of The Plasmodium Falciparum Translocon That Exports Parasite Proteins Into Their Erythocytic Hosts.
Funder
National Health and Medical Research Council
Funding Amount
$409,027.00
Summary
Up to 10% of the world's population will suffer from malaria in any given year and for over a million this disease will be fatal. This devastating disease is caused by the parasite Plasmodium falciparum that infects and destroys our red blood cells. Infected red cells are greatly modified by the parasites so they can feed and avoid elimination by the human immune system. We wish to investigate the red blood cell modification process and assess it as a potential target for anti-malarial drugs.
The Role Of Gonadotropins In Regulating The Production Of Alzheimer's Beta Amyloid
Funder
National Health and Medical Research Council
Funding Amount
$400,278.00
Summary
Currently, about 160,000 Australians suffer from dementia; of which 50-70% are Alzheimer's disease (AD) cases. AD is characterised clinically by memory and personality changes and pathologically by deposition of amyloid. Of particular importance in the disease pathogenesis, is a small molecule called beta amyloid, of which the overproduction is thought to be central to the development of AD. Changes in the levels of the reproductive hormones, particularly low levels of oestrogen during menopause ....Currently, about 160,000 Australians suffer from dementia; of which 50-70% are Alzheimer's disease (AD) cases. AD is characterised clinically by memory and personality changes and pathologically by deposition of amyloid. Of particular importance in the disease pathogenesis, is a small molecule called beta amyloid, of which the overproduction is thought to be central to the development of AD. Changes in the levels of the reproductive hormones, particularly low levels of oestrogen during menopause or testosterone during andropuase, has been associated with the increased risk of developing AD and in altering the levels of beta amyloid. Furthermore, menopause and andropause are also characterised by changes in other reproductive hormones such as the gonadotropins. High levels of the gonadotropins have also been associated with the increased risk of developing AD. Therefore it is important to identify how these changes modify the risk of developing AD. This study examines the role of the gonadotropins in regulating beta amyloid levels in cell culture and in an animal model for AD. Furthermore, this study will assess, in the animal model, the use of gonadotropin lowering agents to reduce levels of beta amyloid. The results from this study will provide important data on how reproductive hormones regulate beta amyloid. Further insight into these mechanisms will provide therapeutic or preventative strategies for AD.Read moreRead less
Mechanisms Of Oxidised Protein Accumulation In Ageing Cells
Funder
National Health and Medical Research Council
Funding Amount
$429,000.00
Summary
Australia has one of the world's most rapidly ageing populations. It is estimated that in 30 years time over 30% of the population will be over 65; many will suffer from a debilitating, age-related disease. The diseases of ageing represent one of the major health challenges this century. Despite their increasing incidence, our understanding of the underlying causes is limited. A common feature is the accumulation of damaged proteins in cells and tissues. Damaged proteins are usually broken down ....Australia has one of the world's most rapidly ageing populations. It is estimated that in 30 years time over 30% of the population will be over 65; many will suffer from a debilitating, age-related disease. The diseases of ageing represent one of the major health challenges this century. Despite their increasing incidence, our understanding of the underlying causes is limited. A common feature is the accumulation of damaged proteins in cells and tissues. Damaged proteins are usually broken down by the cells and replaced, but in many age-related diseases this process fails. The most common source of protein damage is attack by oxygen-derived free radicals. These are by-products of our body's need for oxygen and can originate from atmospheric pollutants. Oxygen rusts metal, makes fat go rancid and can cause irreparable damage to proteins and other biological molecules. Free radical damage contributes to the development of many age-related diseases such as atherosclerosis and neurodegenerative diseases such as Alzheimer's disease. The accumulation of damaged proteins can cause cell death. Our knowledge of the mechanisms by which cells remove proteins damaged by oxygen and the reasons for their accumulation is limited. In this project we will use a novel technique we have developed to generate oxidised proteins in ageing cells. We will identify cellular mechanisms required for the efficient removal of damaged proteins and those mechanisms which fail in ageing cells. We will focus on a group of proteins which protect damaged proteins from aggregating and accumulating and we will examine how we can prevent the accumulation of oxidised proteins by stimulating the body s defence mechanisms. Since the population of Australia is ageing, diseases of ageing are going to consume an increasing amount of the national health budget. A better knowledge of these cellular mechanisms will allow us to design effective prevention and treatment strategies which are at present lacking.Read moreRead less
In cancer cells the normal process of cell death (called apoptosis) is defective, helping abnormal cells to grow and multiply unchecked. The Bak protein is a member of the Bcl-2 family of apoptosis regulators, and plays a pivotal role in mediating cell death. By defining each step in Bak-mediated apoptosis, we aim to better understand how cancer cells accumulate, and how targeting the Bcl-2 family may lead to effective anti-cancer therapeutics.