Pharmacology Of Potential Anti-Tumour Agents: Iron Chelators Of The BpT Class
Funder
National Health and Medical Research Council
Funding Amount
$585,455.00
Summary
Pharmacology of Potential Anti-Tumour Agents: Iron Chelators of the BpT Class Cancer cells have a high iron requirement for DNA synthesis and many clinical trials showed Fe chelators are effective anti-cancer drugs. Their potential to act as anti-tumour agents has been confirmed by the entrance of Triapine into widespread NCI clinical trials. In this NHMRC Renewal, we will perform pharmacological and preclinical studies to promote the development of BpT chelators as novel anti-tumour agents.
Mechanisms Of Glucocorticoid Resistance In Acute Lymphoblastic Leukaemia
Funder
National Health and Medical Research Council
Funding Amount
$547,970.00
Summary
Glucocorticoids are extremely active drugs used in the treatment of childhood acute lymphoblastic leukaemia (ALL), yet a proportion of patients respond poorly to therapy and exhibit resistance at relapse. Clinically relevant mechanisms of glucocorticoid resistance are poorly understood, principally due to lack of appropriate experimental models. This project will reveal novel mechanisms of drug resistance in childhood leukaemia and lead to novel therapeutic strategies to improve outcome.
Examination Of The Molecular Pharmacology Of Anthracyclines Induced Via Their Interaction With Iron
Funder
National Health and Medical Research Council
Funding Amount
$618,401.00
Summary
Anthracyclines are highly effective anti-cancer drugs, but their use is limited by toxic effects on the heart. This is thought to be due to these drugs directly binding iron (Fe). Indeed, we showed that anthracyclines induced marked changes in the way heart cells utilise Fe (DR1-3, 38; Mol. Pharmacol. 2002, 2003, 2004, 2005). We were the first to show that anthracyclines prevent Fe release from the criticial Fe storage protein ferritin. This prevents the use of Fe for vital processes eg. DNA and ....Anthracyclines are highly effective anti-cancer drugs, but their use is limited by toxic effects on the heart. This is thought to be due to these drugs directly binding iron (Fe). Indeed, we showed that anthracyclines induced marked changes in the way heart cells utilise Fe (DR1-3, 38; Mol. Pharmacol. 2002, 2003, 2004, 2005). We were the first to show that anthracyclines prevent Fe release from the criticial Fe storage protein ferritin. This prevents the use of Fe for vital processes eg. DNA and haem synthesis. Hence, this effect probably contributes to the cytotoxic activity of anthracyclines on the heart. We showed that novel drugs developed in my lab that bind Fe called chelators show high activity in animals (DR4) and prevent anthracycline-mediated Fe accumulation in ferritin. Importantly, Fe chelators have been shown to inhibit anthracycline-mediated cardiotoxicity. Indeed, the clinically used cardioprotective agent, ICRF-187, is actually an Fe chelator (5, DR6). However, ICRF-187 is not totally successful in terms of its cardioprotective effects and can cause myelosuppression (5, DR6). While the clinically used chelator, desferrioxamine (DFO), can prevent anthracycline-mediated cardiotoxicity, its poor membrane permeability limits its effectiveness. Our chelators are highly permeable and overcome the disadvantages of DFO (DR4). Thus, they are vital to examine for preventing anthracycline-mediated cardiotoxicity. In this proposal we will examine the changes in Fe metabolism induced by anthracyclines and test the hypothesis that novel Fe chelators may prevent the cardiotoxicity of these agents. We also aim to be the first to assess if preparation of anthracyclines which cannot bind iron prevents their cardiotoxicity. This will be done by preparing metal complexes of these drugs which prevent Fe-binding eg. anthracycline-zinc complexes. These studies are important for the development of less cardiotoxic forms of these very useful anti-tumour agents.Read moreRead less
The Role And Inheritance Of Constitutional Epimutations In Early-onset Colorectal Cancer.
Funder
National Health and Medical Research Council
Funding Amount
$347,551.00
Summary
Traditionally familial cancers are thought to be caused by spelling mistakes within the genetic code of cancer prevention genes. Our group has found that chemical attachments to one gene (MLH1) stops it working, even where there is no spelling mistake, and that those chemical changes can be inherited in families with bowel cancer. We will determine how frequently this type of defect occurs in bowel cancer patients, how and why it arises, and if other cancer genes are similarly affected.
The Role Of Melanoma Tumour Antigen P97 (Melanotransferrin) In Melanoma Tumourigenesis.
Funder
National Health and Medical Research Council
Funding Amount
$563,242.00
Summary
The Role of Melanoma Tumour Antigen p97 (Melanotransferrin) in Melanoma Tumourigenesis Melanotransferrin (MTf) is a homologue of the iron transport protein, transferrin, and was one of the first well characterised melanoma tumour antigens. Our published studies have shown that MTf plays an important role in melanoma tumourigenesis in vivo. In this proposal, we will assess if it is associated with melanoma progression in patient samples and examine its role in melanoma growth and metastasis.
Epimutations As Germ-line Defects In Hereditary Cancer Syndromes
Funder
National Health and Medical Research Council
Funding Amount
$385,925.00
Summary
Traditionally familial cancers were thought to be caused and inherited by spelling mistakes within the genetic code of cancer prevention genes. Our group has found that a 'chemical coat' around the MLH1 gene, causing it to be switched off, can also be inherited in some cases of bowel cancer, without any mistakes within the gene's code. We will determine if this 'coat' causes other types of cancer and if this runs in families. We also hope to find out how the coat is formed and may be reversed.
Chromosomes are structures that carry genes in all our cells. Every human cell has 46 chromosomes. In the nucleus of eukaryotic cells, DNA is highly folded and compacted with specific proteins into a dynamic polymer called chromatin. Gene expression, chromosome division, DNA replication, and repair all act, not on DNA alone, but on this chromatin template. The discovery that enzymes can (re)organise chromatin into accessible and inaccessible configurations revealed mechanisms that considerably e ....Chromosomes are structures that carry genes in all our cells. Every human cell has 46 chromosomes. In the nucleus of eukaryotic cells, DNA is highly folded and compacted with specific proteins into a dynamic polymer called chromatin. Gene expression, chromosome division, DNA replication, and repair all act, not on DNA alone, but on this chromatin template. The discovery that enzymes can (re)organise chromatin into accessible and inaccessible configurations revealed mechanisms that considerably extend the information potential of the genetic code. In addition, it is now established that chromatin structural features can influence gene expression. In vitro studies support a model in which chromatin functions as a barrier for the access to DNA. Therefore this organization has to be tighly regulated and dynamic to allow the protein-DNA interactions critical for nuclear functions. Importantly genome organisation provides in addition to genetic information another layer of information, so called epigenetic, which by definition means that it is stably inherited throughout cellular divisions, yet it is not encoded genetically. Thus each cell type will display a specific epigenome. We have recently constructed small human minichromosomes, which are much easier to study than the much larger normal chromosomes. The present project proposes to define the epigenetic feature across an entire human chromosome using our minichhromosomes as working models. The outcome will be a significant gain in our knowledge on the processes underlying epigenetic regulation, the organisation of specialised chromatin domain, and behaviour of the chromosomes.Read moreRead less