A Tumor Specific Variant Of The EGFR: Characterization And Target For Immunotherapy.
Funder
National Health and Medical Research Council
Funding Amount
$85,570.00
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. This therapeutic approach requires an antibody that specifically binds to cancer cells ....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. This therapeutic approach requires an antibody that specifically binds to cancer cells but not normal cells. In this proposal, we wish to test a novel antibody that binds to a protein on the cell surface called the EGF receptor. While the EGF receptor is found on the surface on many cells, our antibody recognizes a modified version of the EGF receptor that is found exclusively on cancer cells. Previous EGF receptor antibodies tested in the clinic all recognized the normal EGF receptor and thus proved unsuitable as they bound to cells in the liver causing significant side effects. It is anticipated that the specificity of our novel antibodies will overcome this problem. Eventually this antibody could be used to treat patients with brain, breast, prostate and lung cancer. We will also conduct a number of studies to determine the function of this modified receptor. This work will improve our understanding of those events associated with development of tumors.Read moreRead less
Novel Approaches For Activation And Expansion Of Genetically Modified T Cells In Vivo
Funder
National Health and Medical Research Council
Funding Amount
$115,660.00
Summary
Killer T lymphocytes can penetrate tumors and their propagation and transfer into cancer patients has demonstrated some encouraging results, but this form of adoptive immunotherapy remains ineffective in most cancer patients. We propose to improve the tumor trafficking and anti-tumor activities of killer cells by genetically engineering them with proteins that will enable them to recognise and destroy cancer cells. Our previous work has indicated that killer T lymphocytes can be genetically engi ....Killer T lymphocytes can penetrate tumors and their propagation and transfer into cancer patients has demonstrated some encouraging results, but this form of adoptive immunotherapy remains ineffective in most cancer patients. We propose to improve the tumor trafficking and anti-tumor activities of killer cells by genetically engineering them with proteins that will enable them to recognise and destroy cancer cells. Our previous work has indicated that killer T lymphocytes can be genetically engineered in culture with tumor recognition receptors. When transferred into mice, these genetically engineered cells can release toxic and inflammatory proteins that cause tumor destruction. In this proposal we wish to further test this approach in mice by enginneering the mouse killer T cells with (i) receptors that provide stronger signals for killing and proliferation; and (ii) with receptors targeting other structures on tumor cells including the tumor vasculature as a means to overcome tumor escape. In addition, we wish to test a novel approach of combining both genetic engineering and vaccination strategies for expanding gene-modified cells after adoptive transfer. These studies will allow the best receptor genes to be transferred to human white blood cells and examined for anti-tumor effects in immune-deficient mice.Read moreRead less
Cancers have been found to contain 'stem cells' which are responsible for tumours growing and spreading throughout the body. Cancer therapies often target the cancer, but it is now clear the these treatments will only be effective if they can eradicate the malignant stem cells. This research investigates the best way of 'targeting' cancer stem cells in malignant melanoma as a means of developing more effective anti-cancer treatments.
Immunological Mechanisms Of Clinical Responsiveness To Immunotherapy For Metastatic Melanoma
Funder
National Health and Medical Research Council
Funding Amount
$480,750.00
Summary
There have been no major improvements in the treatment of most metastasizing, solid tumours in the last several decades. One avenue that has received much attention is boosting a cancer patient's immune system with an anti-cancer vaccine, so that it destroys just the cancerous cells. This has proved an elusive goal, and no treatment has ever been shown to be of repeated worth, in the complete resolution of multiple sites of metastatic disease, until now. Two consecutive trials of our dendritic c ....There have been no major improvements in the treatment of most metastasizing, solid tumours in the last several decades. One avenue that has received much attention is boosting a cancer patient's immune system with an anti-cancer vaccine, so that it destroys just the cancerous cells. This has proved an elusive goal, and no treatment has ever been shown to be of repeated worth, in the complete resolution of multiple sites of metastatic disease, until now. Two consecutive trials of our dendritic cell based vaccine, which uses only cells from the patient to be treated, have each shown a 15% complete, durable, response rate. The remissions have now lasted longer than 3 years in patients otherwise expected to survive less than 1 year, with no serious side effects observed in any of the patients treated. It is likely that part of the success of this treatment is that it targets unique mutations in the patient's own cancer cells, in combination with a powerful immune stimulation from the dendritic cells. In contrast, most carefully run trials, now and in the recent past, have attempted to use more generic targets, common to many patients' cancers. The problem with this approach is likely to be that the patient is tolerant to these, since the targets are common, self proteins. At variance with all previous trials, we found an exact correlation between durable clinical responses and the degree of anti-tumour immunity displayed by the patients T cells. This grant proposal is based on the reasoning that, by studying in depth the characteristics of this successful immune response, in patients with complete, durable, clinical responses, we will be able to make major improvements in the formulation of the therapy.Read moreRead less
Immunoregulatory Immune Responses To A Peripherally Presented Tumour Antigen
Funder
National Health and Medical Research Council
Funding Amount
$219,750.00
Summary
Tumours express proteins which the body can recognise as foreign. However, the recognition process often goes wrong, leaving the body's defences against infection unable to respond to the tumour. This lack of response may become permanent, and the tumour may then be protected by the immune system. We have a model system, based on cervical cancer, in which we can determine the reasons why tumour tolerance can occur, and explore ways of overcoming the tolerance
Although the immune system has the ability to reject tumours, this sometimes does not occur, leading to cancer. There are many different types of cells that make up the immune system, including some which respond very early, called natural killer (NK) and NKT cells. These cells are the first line of defence against some tumours, although we do not understand how they recognise and respond to tumour cells. The aim of this project is to investigate the functional importance of both NK and NKT cell ....Although the immune system has the ability to reject tumours, this sometimes does not occur, leading to cancer. There are many different types of cells that make up the immune system, including some which respond very early, called natural killer (NK) and NKT cells. These cells are the first line of defence against some tumours, although we do not understand how they recognise and respond to tumour cells. The aim of this project is to investigate the functional importance of both NK and NKT cells in response to a range of different tumour types, including melanoma (skin cancer), lung carcinoma, breast carcinoma and sarcoma (connective tissue tumour). We will test the importance of each of these subsets by injecting these tumours into mice that have specific deficiencies in NK and-or NKT cells. If the NK or NKT cells are important, the tumours should grow more effectively when these immune cells are absent. We will also be able to put NK and-or NKT cells back into the mice to show directly that they are responsible for tumour rejection. Using a modification of this cell transfer approach, we will be able to inhibit special molecules that are normally produced by these cells that help them interact with other cells, and also help them attack the tumour cells. Collectively, the approaches outlined in this application allow us to determine which types of cells are important in response to a broad range of different tumour types, and also should tell us how these cells are able to attack the tumours. This information will be invaluable for the development of new strategies to use the patients immune system to attack cancer (known as immuno-therapy).Read moreRead less
A Vaccine To Break Tolerance To Cervical Carcinoma Oncoprotein
Funder
National Health and Medical Research Council
Funding Amount
$212,036.00
Summary
Evidence that cervical cancer is caused by Human Papillomavirus is compelling. Once the virus enters the cells of the cervix, it produces a protein named E7 which functions to make the cells cancerous. Cervical cancer is the fifth commonest cause of death in women in Australia, and the major killer of women world-wide. The E7 protein is the ideal target for a vaccine since it occurs only in the tumour cells. Cervical tumour cells are killed by specialised immune system cells termed CTLs which re ....Evidence that cervical cancer is caused by Human Papillomavirus is compelling. Once the virus enters the cells of the cervix, it produces a protein named E7 which functions to make the cells cancerous. Cervical cancer is the fifth commonest cause of death in women in Australia, and the major killer of women world-wide. The E7 protein is the ideal target for a vaccine since it occurs only in the tumour cells. Cervical tumour cells are killed by specialised immune system cells termed CTLs which recognised fragments of the E7 molecule on their surface, bound to 'self' MHC molecules. Our laboratory has developed several mouse models of human cervical cancer, and has worked out which parts of the E7 protein are important in developing an appropriate immune response to control tumour growth. However a major finding is that the E7 molecules render the CTL cell population incapable of making an appropriate response to kill the tumour cells. We believe that this process, termed 'tolerance induction' can be overcome by using a novel approach as follows. Specialised antigen presenting cells , termed 'dendritic cells' (DCs) will be isolated and made to produce E7 protein by infecting them with a geneticlly modified virus (Adenovirus) which expresses E7 and specialised DC activators molecules, but is incapable of itself replicating. The dendritic cells will be re-introduced into the host as a vaccine, and will present the E7 to the immune system in such a way that tolerance will be broken. In other words the vaccine recipient will again be able to make a CTL immune response to the E7 protein in their tumours, and so be able to kill the tumour cells.Read moreRead less
A Polyepitope HPV16 E7 DNA Vaccine Restricted Through Multiple Class 1 Haplotypes Protects Against E7-expressing Tumour
Funder
National Health and Medical Research Council
Funding Amount
$218,244.00
Summary
Evidence that cervical cancer is caused by Human Papillomavirus is compelling. Once the virus enters the cells of the cervix, it produces a protein named E7 which functions to make the cells cancerous. Cervical cancer is the 5th commonest cause of death in women in Australia, and the major killer of women world-wide.The disease is particularly severe in those women whose immune systems are impaired, indicating immunological control of the cancerous cells . Current therapies including surgical re ....Evidence that cervical cancer is caused by Human Papillomavirus is compelling. Once the virus enters the cells of the cervix, it produces a protein named E7 which functions to make the cells cancerous. Cervical cancer is the 5th commonest cause of death in women in Australia, and the major killer of women world-wide.The disease is particularly severe in those women whose immune systems are impaired, indicating immunological control of the cancerous cells . Current therapies including surgical removal are frequently inadequate, and the r is no effective drug to combat the virus.These observations indicate that a vaccine is warranted, and that the E7 protein may be an ideal target for the vaccine. Cervical tumour cells are killed by specialised immune system cells named CTLs which recognise fragments of foreign antigen(E7) on their surface bound to selfMHC molecules. Our work has shown that multiple antigen fragments can be encoded and stitched together in a genetic vaccine which will stimulate CTLs to function in a number of 'self'molecule situations Our laboratory has developed several mouse models of human cervical cancer , and (along with others) has worked out which parts of the E7 protein are importatnt in developing an appropriate immune response to control tumour growth when given as a vaccine. One animal model consists of mice which are genetically engineered to produce several types of selfmolecules and also E7. Thes mice develop skin tumours as result of E7 expression. This system provides model of cervical epithelial tumours caused by E7 expression in women.Thus we can ask the questions o can we elicit CTL responses which function in the context of humanself ? o Will these CTL responses prevent the growth of E7-induced epithelial tumours? The OUTCOME of the project will be a vaccine which will prevent the establishment of cervical cancer which can progress directly into clinical trials in women bearing appropriate selfmolecules.Read moreRead less
An Integrated Approach For The Efffective Adoptive Immunotherapy Of Cancer
Funder
National Health and Medical Research Council
Funding Amount
$468,119.00
Summary
Killer T lymphocytes can penetrate tumors and their transfer into cancer patients has demonstrated some encouraging results, but this form of immunotherapy remain ineffective in most cancer patients. We propose to improve the tumor trafficking and anti-tumor activities of killer cells by genetically engineering them with proteins that will enable them to recognise and destroy cancer cells. The outcomes of this project will validate this novel approach for treatment of cancer patients.