Tumour B-cells From Lymphomas Are Resistant To ATP-mediated Apoptosis Due To Non-functional P2X7 Receptors
Funder
National Health and Medical Research Council
Funding Amount
$226,320.00
Summary
Adenosine triphosphate (ATP) is an important constituent normally present inside cells. When added to normal lymphocytes (or released by cells lining the vessel wall or in lymph nodes), ATP acts from outside these cells to open a pore as well as activate an enzyme which digests the lipid envelope of the cell. This loss of lipid covering of the cell produces a leakiness to various constituents of the cell which gradually leads to death of normal lymphocytes. However in the malignant lymphocytes o ....Adenosine triphosphate (ATP) is an important constituent normally present inside cells. When added to normal lymphocytes (or released by cells lining the vessel wall or in lymph nodes), ATP acts from outside these cells to open a pore as well as activate an enzyme which digests the lipid envelope of the cell. This loss of lipid covering of the cell produces a leakiness to various constituents of the cell which gradually leads to death of normal lymphocytes. However in the malignant lymphocytes of human lymphomas this mechanism of cell death does not operate. The loss of function of this 'death receptor' explains why in the lymphomas there is a progressive accumulation of malignant lymphocytes which give enlargement of lymph nodes and spleen and leads to death of the patient. Knowledge of the defect in this pathway of cell death will enable new strategies to be introduced to control this malignant disease.Read moreRead less
Dissecting FLT3 Signalling In Acute Myeloid Leukaemia
Funder
National Health and Medical Research Council
Funding Amount
$498,328.00
Summary
Each year approximately 6000 Australian adults and children are diagnosed with leukaemia, lymphoma or a related blood disorder, accounting for about 15% of all cancers. Acute Myeloid Leukaemia (AML) is the most common form of leukaemia in adults resulting from an accumulation of immature myeloid cells in the bone marrow and peripheral blood as a result of sustained, abnormal cell growth and survival together with a block in normal blood cell formation. There is still a major research effort aime ....Each year approximately 6000 Australian adults and children are diagnosed with leukaemia, lymphoma or a related blood disorder, accounting for about 15% of all cancers. Acute Myeloid Leukaemia (AML) is the most common form of leukaemia in adults resulting from an accumulation of immature myeloid cells in the bone marrow and peripheral blood as a result of sustained, abnormal cell growth and survival together with a block in normal blood cell formation. There is still a major research effort aimed at understanding the mechanisms that lead to AML formation and it is clear that multiple AML oncogenes and tumour suppressors remain to be identified. Identification of further events involved in AML is important as it will provide avenues for more specific and less toxic treatments. These are needed because current success rates for AML remain relatively poor. It is critical that research into the understanding of the pathways and events involved in AML keeps pace with the rapid development of new approaches for therapeutic agents. Together this will greatly increase the scope for therapeutic intervention over the next decade. In this application we investigate the role of a new molecular pathway in AML. Our studies have identified a gene of particular interest that we propose normally prevents AML formation and therefore is frequently turned off by the cellular changes that lead to AML. We propose that silencing of this gene is particularly important in those AML cases which have mutations in the cell surface receptor FLT3 (about 30% of AML cases). We will use a number of molecular and cell biology approaches to manipulate this gene in mouse cell lines, normal mouse cells and human AML cells. A better understanding of the role of this gene and the associated pathway involving FLT3 may generate new leads for therapeutic approaches.Read moreRead less
Microenvironmental Regulation Of Blood Cells By Retinoic Acid Receptor Gamma.
Funder
National Health and Medical Research Council
Funding Amount
$958,428.00
Summary
Vitamin A deficiency causes profound effects in humans, with anaemia and an inability to fight infection being consequences of vitamin A deficiency on blood cells. We have evidence that these effects of vitamin A deficiency occur via one of the receptors for vitamin A. Furthermore, these effects are due to changes in the non-blood cells that help to make blood cells. By understanding how this occurs we may identify better treatments for patients with impaired immune systems.
CXCR4 Antagonists In Acute Lymphoblastic Leukemias In NOD/SCID Mice
Funder
National Health and Medical Research Council
Funding Amount
$505,500.00
Summary
Acute lymphoblastic leukemia (ALL) is the most common form of childhood cancer and a major cause of death in children. Although ALL is usually responsive to chemotherapy, about 25% of children and 65% of adults with ALL develop a relapse of their disease. The majority of these patients will die of leukemia. New approaches to the treatment of ALL are necessary to obtain cures for these patients. We have identified stromal-derived factor (SDF)-1 as a major regulator of ALL cell growth and survival ....Acute lymphoblastic leukemia (ALL) is the most common form of childhood cancer and a major cause of death in children. Although ALL is usually responsive to chemotherapy, about 25% of children and 65% of adults with ALL develop a relapse of their disease. The majority of these patients will die of leukemia. New approaches to the treatment of ALL are necessary to obtain cures for these patients. We have identified stromal-derived factor (SDF)-1 as a major regulator of ALL cell growth and survival. It is currently the only known factor that significantly stimulates the growth-survival of cells from the majority of patients with ALL. Specific antagonists of the SDF-1 receptor, CXCR4, are available. Depriving ALL cells of SDF-1 by the use of these antagonists provides a radically new approach for the treatment of ALL. CXCR4 antagonists also increase the susceptibility of ALL cells to cytotoxic drugs. The mechanisms by which SDF-1 promotes ALL cell growth and survival are not known but appear to be largely due to synergistic interactions with other molecules that have little or no effect on their own. Knowledge of the underlying mechanisms of action of SDF-1 and the factors with which it synergises will facilitate for the further development of this approach. This project will examine the modulation of the expression of proteins that regulate ALL cell growth and survival by CXCR4 antagonists, providing insights into how CXCR4 antagonists work. This project will also extend our encouraging data obtained using tissue culture to an animal model of leukemia. The antagonists will be tested in isolation and in combination with currently used chemotherapy agents. It is expected that CXCR4 antagonists will inhibit the growth of ALL cells and increase their sensitivity to chemotherapy agents in the animal model as we have seen in laboratory culture. The addition of CXCR4 antagonists to current treatment protocols is expected to significantly improve the outcome for patients.Read moreRead less
Dissecting The Role Of The IL-3 Receptor Alpha Subunit And Beta-catenin In Acute Myeloid Leukaemia
Funder
National Health and Medical Research Council
Funding Amount
$583,312.00
Summary
Leukaemia is a devastating form of blood cancer affecting both young and old. We aim to understand the mechanisms of uncontrolled cell growth associated with acute myeloid leukaemia. We focus on the role of key growth regulators that are abnormally active in the critical leukaemia stem cells. Understanding the biological and molecular properties of these cells is of considerable importance for development of the next generation of leukaemia therapies.
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.