The Biology And Clinical Manifestations Of Chronic Myeloid Leukaemia
Funder
National Health and Medical Research Council
Funding Amount
$440,583.00
Summary
I am a haematologist studying the biology and clinical manifestations of chronic myeloid leukaemia with particular reference to the dynamics of response to kinase inhibitor therapy and the causes and clinical management of suboptimal response and drug res
Development And Assessment Of Novel Assays To Predict Response To Second-line TKI Therapy In Imatinib-resistant CML
Funder
National Health and Medical Research Council
Funding Amount
$491,308.00
Summary
Patients with chronic myeloid leukaemia (CML) respond well to imatinib, the first small molecule developed to block the kinase activity of the causative oncogene in CML, BCR-ABL. However some patients develop resistance. Several new kinase inhibitors are now available that are effective in some patients with imatinib resistance. We plan to develop biological and molecular assays to predict if a CML patient will respond to a specific second-line kinase inhibitor to optimise second-line therapy.
The Role Of Intracellular Uptake And Retention Of Abl Kinase Inhibitors In Modifying Clinical Response In CML
Funder
National Health and Medical Research Council
Funding Amount
$465,210.00
Summary
Imatinib is one of the first targeted anticancer drugs to be clinically developed. It is designed to inhibit the kinase activity of BCR-ABL, a mutant protein found in some cases of leukaemia, particularly chronic myeloid leukaemia. Blocking the kinase activity of BCR-ABL has proven to be highly effective therapy for most patients, achieving prolonged remissions and significantly improving survival. However resistance to imatinib is a problem, including failure to respond to imatinib, loss of res ....Imatinib is one of the first targeted anticancer drugs to be clinically developed. It is designed to inhibit the kinase activity of BCR-ABL, a mutant protein found in some cases of leukaemia, particularly chronic myeloid leukaemia. Blocking the kinase activity of BCR-ABL has proven to be highly effective therapy for most patients, achieving prolonged remissions and significantly improving survival. However resistance to imatinib is a problem, including failure to respond to imatinib, loss of response, and long term persistence of low levels of leukaemia. New ABL kinase inhibitors (AKIs) have been developed that are more potent than imatinib, but they also appear to be prone to resistance. One potentially important cause of resistance to AKIs is the ability of some leukaemic cells to modify their cellular pathways to reduce the effective concentration of the drug by either reducing its movement into the cell (influx) or increasing its movement out (efflux). We will investigate the mechanisms used by resistant leukaemic cells to reduce intracellular drug levels of these AKIs and test ways of countering these effects by blocking the proteins responsible for drug efflux or promoting drug influx. These studies will use our stored collections of leukaemic cells from responsive and resistant patients to determine the importance of specific influx and efflux pumps. It will help to identify patients where this form of resistance is limiting response. This may allow us to develop more effective AKIs that are less prone to these forms of drug resistance. We will also test whether other anti-cancer drugs have an impact on AKI drug transport because this could reduce the effectiveness of combination treatment. The effects on drug transport of concomitant administration of commonly used drugs together with AKIs will also be studied because this can reduce the effectiveness of AKis or in some cases improve their effectiveness by increasing their uptake and retention.Read moreRead less
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
Use Of Retroviral Expression Libraries To Characterise Mechanisms Of Drug Resistance In Leukaemia.
Funder
National Health and Medical Research Council
Funding Amount
$362,545.00
Summary
At present, treatment of leukaemia is based either on established chemotherapeutic drug treatment or newly identified inhibitor drugs currently being tested as part of clinical trials. Both these treatments are known to induce or select for resistance to the drugs in some cases. Resistance usually reduces the success rate of any further treatment with the same or similar drugs. To discover possible ways of overcoming drug resistance it is important to understand the mechanisms that are responsib ....At present, treatment of leukaemia is based either on established chemotherapeutic drug treatment or newly identified inhibitor drugs currently being tested as part of clinical trials. Both these treatments are known to induce or select for resistance to the drugs in some cases. Resistance usually reduces the success rate of any further treatment with the same or similar drugs. To discover possible ways of overcoming drug resistance it is important to understand the mechanisms that are responsible. To date a number of mechanisms that cause resistance are known, but there are still unidentified mechanisms that are associated with drug resistance. The aim of our work is to use a new method to identify unknown drug resistance mechanisms in leukaemia. Once a mechanism is identified, we will determine its relevance in leukaemia by screening a number of patients that have shown resistance to treatment. If identified as a common mechanism of resistance in leukaemic patients, we will test possible agents able to prevent drug resistance that could be used in conjunction with drug during treatment, and to screen new drugs for susceptibility to resistance mechanisms. Diagnostic tests to detect the presence of the known resistance mechanisms prior to treatment could be used in selection of the most appropriate drug combinations for individual patients. Some of the known drug resistance mechanisms that occur in leukaemia are also operative in other forms of cancer and the project is of general relevance to cancer chemotherapy.Read moreRead less