Characterisation Of A New Family Of Proteins Involved In Cell Signalling, RNA Metabolism And Cancer
Funder
National Health and Medical Research Council
Funding Amount
$200,880.00
Summary
We have discovered a novel RNA-binding protein (G3BP-2) that is involved in responding to external signals, such as growth factors, at the level of gene expression. Other RNA-binding proteins belonging to the same broad group of proteins are responsible for a host of disease states in mammals including mental retardation, myotonic dystrophy, Huntington?s disease and cancers. Considering the wealth of knowledge accumulated that implicates these proteins to human dysfunction surprisingly few of th ....We have discovered a novel RNA-binding protein (G3BP-2) that is involved in responding to external signals, such as growth factors, at the level of gene expression. Other RNA-binding proteins belonging to the same broad group of proteins are responsible for a host of disease states in mammals including mental retardation, myotonic dystrophy, Huntington?s disease and cancers. Considering the wealth of knowledge accumulated that implicates these proteins to human dysfunction surprisingly few of these RNA-binding proteins have been identified. We have shown that the novel protein discovered in our laboratory is perturbed in cancer and we are interested in characterising its putative role in cancer. The results established in our laboratory so far would indicate that generally, G3BP-2 is expressed in normal tissue and it expression changes in some cancers studied so far. Considering that G3BP-2 lies in a pathway known to be involved in cancer progression it is important to understand what effects the inappropriate expression of G3BP-2 may have on cancer progression and survival. This project is designed to characterise what signals the cell uses to control these proteins and in turn which genes these may effect. In this way we may be able to determine how external signals may effect tumour progression and on what genes this influence is expressed. It would be hoped that this project would increase our understanding of cancer and potentially lead to new diagnostic reagents and therapies in the treatment of cancer.Read moreRead less
Regulation Of BRCA1 And APC Tumour Suppressor Functions By Nuclear Export
Funder
National Health and Medical Research Council
Funding Amount
$433,500.00
Summary
Cancer cells are unique, in that their ability to divide and grow is no longer controlled. Moreover, the DNA of cancer cells is less stable, and vital control genes often gain small mutations which culminate in a more aggressive or malignant cancer cell. Cancers from different tissues progress and respond in different ways to treatment, and the eventual development of tailored treatments or therapies will require a detailed understanding of how cancers from different tissues arise. Our laborator ....Cancer cells are unique, in that their ability to divide and grow is no longer controlled. Moreover, the DNA of cancer cells is less stable, and vital control genes often gain small mutations which culminate in a more aggressive or malignant cancer cell. Cancers from different tissues progress and respond in different ways to treatment, and the eventual development of tailored treatments or therapies will require a detailed understanding of how cancers from different tissues arise. Our laboratory studies two proteins, BRCA1 and APC, which are encoded by the genes most often associated with breast and colon cancer, respectively. We have made important discoveries linking the movement and location of these proteins inside the cell with their cancer-causing activity. In this project, we will continue to study how and why APC and BRCA1 move between different compartments inside cancer cells, and how this movement can sometimes signal cancer cells to die. Detailed understanding of these processes is essential for the eventual design of drug, peptide or gene therapies aimed at correcting defects in the expression or localisation of APC or BRCA1 in breast or colon cancer cells, and hopefully provide clues for that magic bullet that specifically targets and kills cancer cells.Read moreRead less
Analysis Of The C-terminal Hypervariable Region Of Ras Proteins
Funder
National Health and Medical Research Council
Funding Amount
$419,241.00
Summary
In human cancers one or more of the signaling pathways leading from growth factor receptors at the cell surface to the nucleus where cell division is initiated are subverted. For example, a protein called Ras, that regulates one major signaling pathway, is mutated in 90% of pancreatic cancers, 50% of colon cancers and 30% of acute leukaemias. This leaves Ras and the signaling pathway permanently switched on causing uncontrolled cell proliferation. The clinical impact of drugs that could neutrali ....In human cancers one or more of the signaling pathways leading from growth factor receptors at the cell surface to the nucleus where cell division is initiated are subverted. For example, a protein called Ras, that regulates one major signaling pathway, is mutated in 90% of pancreatic cancers, 50% of colon cancers and 30% of acute leukaemias. This leaves Ras and the signaling pathway permanently switched on causing uncontrolled cell proliferation. The clinical impact of drugs that could neutralise Ras function in these tumours is potentially enormous. Our previous work demonstrated that Ras must be attached to the inner surface of the cell membrane in order to function properly. This project now seeks to understand exactly how Ras gets to and attaches to the cell membrane. Once we understand this mechanism drugs can be designed to block Ras getting to the membrane. Such drugs should neutralize the effect of Ras in tumours and control cell proliferation. In fact, our previous study has already led to the identification of the first generation of anti-Ras drugs that work on this principle.Read moreRead less
Regulation Of The Tumour Suppressors APC And BRCA1 By Nuclear Export
Funder
National Health and Medical Research Council
Funding Amount
$530,874.00
Summary
Cancer cells lack the ability to control their own growth, and thus continously divide in their local environment, leading to tumour formation. Tumour suppressor proteins, like APC and BRCA1, normally function as regulators to help cells respond to outside signals and to stop growing when necessary. The inactivation and altered cellular localisation of tumour suppressor proteins can contribute to cancer development. We have found that the APC and BRCA1 proteins, whose inactivation leads to devel ....Cancer cells lack the ability to control their own growth, and thus continously divide in their local environment, leading to tumour formation. Tumour suppressor proteins, like APC and BRCA1, normally function as regulators to help cells respond to outside signals and to stop growing when necessary. The inactivation and altered cellular localisation of tumour suppressor proteins can contribute to cancer development. We have found that the APC and BRCA1 proteins, whose inactivation leads to development of colon cancer and breast cancer, respectively, contain signals that dictate their movement within the cell. Our novel preliminary findings reveal that APC and BRCA1 are able to move in and out of the cell nucleus. We aim to define how this occurs, and examine how the regulation of their cellular location affects the normal function of these cancer-suppressing proteins. Finally, abnormalities in the nuclear passage of APC or BRCA1 might explain their altered cellular location in cancer cells.Read moreRead less
The Role Of Plasma Membrane Microdomains In Regulating Ras-dependent Raf Activation
Funder
National Health and Medical Research Council
Funding Amount
$216,100.00
Summary
In human cancers one or more of the signaling pathways leading from growth factor receptors at the cell surface to the nucleus where cell division is initiated are subverted. For example, a protein called Ras, that regulates a series of major signaling pathways, is mutated in 25% of all human tumours. This leaves Ras and the signaling pathways permanently switched on causing uncontrolled cell proliferation. Our previous work has demonstrated that Ras must be attached to the inner surface of the ....In human cancers one or more of the signaling pathways leading from growth factor receptors at the cell surface to the nucleus where cell division is initiated are subverted. For example, a protein called Ras, that regulates a series of major signaling pathways, is mutated in 25% of all human tumours. This leaves Ras and the signaling pathways permanently switched on causing uncontrolled cell proliferation. Our previous work has demonstrated that Ras must be attached to the inner surface of the cell membrane in order to function properly. This project now seeks to understand exactly how Ras attaches to and interacts with specific sites in the plasma membrane. Its is becoming clear that different isoforms of Ras, called H-, N- and K-ras have different functions in the cell which may in turn result from their different sites of attachment to the cell membrane. This is important because by understanding the precise micro-environment in which the different Ras proteins operate and how they activate subsequent proteins in their signaling networks we will be in a good position to design drugs that selectively compromise the function of each specific Ras isoform. A highly relevant example is provided by K-ras which is mutated in 90% of all pancreatic cancers and 50% of all colon cancers. Clearly the clinical impact of a drug that could selectively neutralise K-Ras function in these tumours is potentially enormous.Read moreRead less
Colorectal cancer is a common malignancy in Australia and the mutation of one gene (Apc) is implicated in >80% of the cases. We aim to understand Apc biochemistry in normal and colon cancer cells by integrating mathematics with our experimental biology program. The main outcomes for this project will be a better understanding of the regulatory systems perturbed in colon cancer. We believe that the insights gained by our research will point the way to more effective treatments of colon cancer.
Analysis Of APC And APC Protein Complexes In Colon Cancer
Funder
National Health and Medical Research Council
Funding Amount
$110,786.00
Summary
Colorectal cancer is one of the foremost causes of death in Australia. A defective form of a protein called APC has been shown to be present in more than 80% of colon tumours. How APC contributes to colon cancer is still not known. We aim to determine the function of the APC protein by studying the APC protein and proteins that interact with APC in normal and cancerous colon epithelial cells. We will use cells derived from normal colon epithelium as well as from colon carcinomas. Once we have id ....Colorectal cancer is one of the foremost causes of death in Australia. A defective form of a protein called APC has been shown to be present in more than 80% of colon tumours. How APC contributes to colon cancer is still not known. We aim to determine the function of the APC protein by studying the APC protein and proteins that interact with APC in normal and cancerous colon epithelial cells. We will use cells derived from normal colon epithelium as well as from colon carcinomas. Once we have identified proteins that interact with APC in normal colonic cells, we will have a more complete understanding of the function of APC and its role in the development of colonic tumours.Read moreRead less
Targeting Of The APC Tumour Suppressor To Mitochondria: Implications For APC Regulation And Cellular Function
Funder
National Health and Medical Research Council
Funding Amount
$390,116.00
Summary
Inherited mutations in the APC gene cause colon cancer, and kills 4,700 Australians every year. About 1 in 21 Australians develop colorectal cancer by the age of 75. APC mutations change cells in different ways, triggering the cancer process. We have discovered a new pathway, involving altered movement of APC to mitochondria in tumour cells. This study will investigate how this cancerous change may help our understanding of colon cancer progression.