Gastrokine 2: A Novel Stomach-specific Tumour Suppressor Gene
Funder
National Health and Medical Research Council
Funding Amount
$342,735.00
Summary
We will evaluate how a natural protein called gastrokine 2 acts to prevent cancer from developing in the stomach. We will show how gastrokine 2 interacts with another stomach protein TFF1, to block the effects of the inflammatory and cancer causing bacterium Helicobacter pylori, and the way that this bacterium circumvents this by turning off the production of gastrokine 2. Finally a drug which inhibits stomach tumour growth by turning on gastrokine 2 will be tested.
Progastrin Derived Peptides: Biological Activities And Functions In The Gastrointestinal Tract
Funder
National Health and Medical Research Council
Funding Amount
$454,500.00
Summary
Gastrin is a hormone from the stomach which aids digestion by stimulating acid secretion. However too much acid can cause ulcers of the gastrointestinal tract. Gastrin also stimulates the growth of the lining of the stomach and intestines. This growth promoting effect is important for the development of the gastrointestinal tract before birth and may also be involved in a number of cancers especially colon cancer. Several different forms of gastrin are made by endocrine cells of the stomach and ....Gastrin is a hormone from the stomach which aids digestion by stimulating acid secretion. However too much acid can cause ulcers of the gastrointestinal tract. Gastrin also stimulates the growth of the lining of the stomach and intestines. This growth promoting effect is important for the development of the gastrointestinal tract before birth and may also be involved in a number of cancers especially colon cancer. Several different forms of gastrin are made by endocrine cells of the stomach and by cancers of the colon. It seems that the different types of gastrins have different effects and act through distinct receptors, but we do not know which are the most important forms and whether all forms are biologically active. The amount, type and activity of the different gastrins, and the regions of the molecule that are essential for biological activity, will be investigated using cell lines, animal models that overproduce too much gastrin, animal models of colon cancer and in patients with colon cancer. Colorectal carcinoma (cancer of the large bowel) is the second most common cause of cancer death. A successful outcome will result in the development of assays for the early diagnosis and monitoring of bowel cancer and the potential for novel treatments such as gastrin receptor antagonists and radiolabelled gastrin analogues for radiotherapy.Read moreRead less
SFRP4 As A Novel Diagnostic And Therapeutic Target For Gastric Cancer
Funder
National Health and Medical Research Council
Funding Amount
$137,700.00
Summary
Gastric cancer is a common cancer with poor survival, but is and potentially curable when diagnosed at an early stage. However currently there are no non-invasive markers for the early detection of gastric cancer, and treatments for advanced cancer are limited. Secreted frizzled related protein 4 (SFRP4) is a protein that is thought to play a role in invasion of gastric cancer. This study will investigate the utility SFRP4 as a diagnostic test and possible therapeutic for gastric cancer.
Genome-wide Expression Analysis In Advanced Gastric Cancer
Funder
National Health and Medical Research Council
Funding Amount
$326,761.00
Summary
Gastric cancer is the fourth ranked cancer by mortality in Australia. Therapy of gastric cancer is unsatisfactory for two reasons; firstly, how normal stomach cells become cancerous is not well defined. We know long-term infection with the bacteria Helicobacter can lead to these cancers, as can severe acid reflux. The cancers produced by these very different agents look remarkably similar, but must be arising through different pathways. Research to date has not yielded great insight. Secondly, e ....Gastric cancer is the fourth ranked cancer by mortality in Australia. Therapy of gastric cancer is unsatisfactory for two reasons; firstly, how normal stomach cells become cancerous is not well defined. We know long-term infection with the bacteria Helicobacter can lead to these cancers, as can severe acid reflux. The cancers produced by these very different agents look remarkably similar, but must be arising through different pathways. Research to date has not yielded great insight. Secondly, existing therapy, especially chemotherapy, tends to provide a Oone size fits all? solution. Whatever the cause, removal at surgery is the best option for treatment. After this, patients are often treated with chemotherapy. Although improvements in patient comfort have been made, very few patients are cured as a result of this treatment. We need more information with which to match the right patient with the right therapy. We will perform high-throughput analysis of comprehensive arrays of human genes that are affected in gastric cancer. Biopsies from cancerous and normal tissue will be obtained when patients have surgery. This tissue will have the RNA (the Omessage? from each gene) labelled with chemical tags and then applied to DNA Omicrochips?. Each microchip contains about 5000 gene targets; the RNA binds the matching DNA and produces a light reaction. We can read the light output from these 5000 (or more) signals, and perform complex statistical analysis on the results. This will result in several specific Ogene expression profiles? which we will analyse to see which profiles match each situation. Profiles matching reflux-induced cancer and Helicobacter-induced cancer can be compared. This will suggest what unique processes are occurring in the cancer cells. Profiles of patients responding well to therapy may allow the use of Otailor-made? therapy. In the future, insight into cancer pathways should also allow the design of new and more successful therapies.Read moreRead less
The Opposing Roles Of STAT1 And STAT3 Signalling By IL-6 Family Cytokines In Inflammation And Tumourigenesis
Funder
National Health and Medical Research Council
Funding Amount
$472,770.00
Summary
Stomach cancer is the second most common cause of cancer-related deaths worldwide, and results in the yearly death of several thousand people in Australia alone. We have discovered a specific mutation in a gene for a receptor molecule called gp130 that results in the formation of stomach cancer in mice. Strikingly, mice with this mutation are also highly susceptible to clinically-relevant experimental models of septic shock and peritonitis, two chronic inflammatory disorders induced by bacterial ....Stomach cancer is the second most common cause of cancer-related deaths worldwide, and results in the yearly death of several thousand people in Australia alone. We have discovered a specific mutation in a gene for a receptor molecule called gp130 that results in the formation of stomach cancer in mice. Strikingly, mice with this mutation are also highly susceptible to clinically-relevant experimental models of septic shock and peritonitis, two chronic inflammatory disorders induced by bacterial infection. We are now aiming to understand the exact molecular events by which this mutation results in the uncontrolled growth of epithelial cells that line the stomach wall, as well as uncontrolled regulation of the immune system leading to local and systemic inflammation. At the molecular level, the mutation in gp130 leads to over-activation of two signalling molecules, Stat1 and Stat3, which are also used by a range of other receptors to transmit specific cellular responses. In the context of cancer and inflammation, Stat1 and Stat3 have opposing roles (ie Stat3 promotes cancer and can be both anti-pro-inflammatory, while Stat1 suppresses cancer and is pro-inflammatory), although as yet, the contribution of the gp130 receptor in directing Stat1 and Stat3 activation in these disorders is not known. Our proposal employs established strategies and unique mouse models to specifically address how the mutation in gp130 can orchestrate the opposing biological functions of these two molecules to drive stomach cancer and inflammation. The identification of mechanisms by which gp130-dependent activation of these two molecules causally relate to inflammation and stomach cancer will ultimately provide novel and rational approaches to target these molecules for the screening and treatment of various inflammatory disorders and cancers, including those of the stomach.Read moreRead less
Cross-talk Between Cytokine And Pathogen Recognition Receptor Networks In The Pathogenesis Of Gastric Cancer
Funder
National Health and Medical Research Council
Funding Amount
$174,800.00
Summary
Stomach cancer is the second most common cause of cancer-related deaths worldwide, and results in the yearly death of several thousand people in Australia alone. We have discovered a specific mutation in a gene called gp130 that results in the formation of gastritis and stomach cancer in mice. We are now aiming to understand the exact molecular events by which this mutation results in chronic inflammation and the subsequent uncontrolled growth of epithelial cells that line the stomach wall.
Tumour Associated Macrophages And The IL-6 Family Of Cytokines In The Progression To Gastric Cancer
Funder
National Health and Medical Research Council
Funding Amount
$522,602.00
Summary
Stomach cancer has a high mortality rate and a poor prognosis. Stomach cancer is one of the few cancers in which the causative pathogen had been demonstrated and eradication of Helicobacter pylori will eliminate the risk of developing cancer but the point at which tumour initiation is irreversible is unknown. Eradication of H. pylori is not always simple or effective. So investigation into initiation events in stomach cancer and development of more sophisticated treatments is warranted.
Physiology And Pathology Of Novel Forms Of Progastrin
Funder
National Health and Medical Research Council
Funding Amount
$589,175.00
Summary
Gastrin is a stomach hormone which increases acid secretion and the growth of the stomach and bowel. This growth promoting effect may be involved in a number of cancers especially colon cancer. The different types of gastrins have different effects but we do not know which forms are important and whether all are active. The types and activity of the different gastrins will be investigated using cell lines, animal models and colon cancer patients with the view of establishing new treatments.
Regulation Of The Tumour Suppressor PTEN By Phosphorylation And Oligomerization
Funder
National Health and Medical Research Council
Funding Amount
$241,650.00
Summary
The tumour suppressor PTEN is an enzyme involved in controlling cell growth, cell death, and cell migration. PTEN was identified as a tumour suppressor because many tumour cells were found to carry mutations in the PTEN gene that cause the loss of PTEN protein or the loss of PTEN enzyme activity. Hereditary mutations of the PTEN gene are the causes of a rare genetic disease called Cowden's disease. Cowden's disease patients are predisposed to developing skin, thyroid, and breast cancers. In labo ....The tumour suppressor PTEN is an enzyme involved in controlling cell growth, cell death, and cell migration. PTEN was identified as a tumour suppressor because many tumour cells were found to carry mutations in the PTEN gene that cause the loss of PTEN protein or the loss of PTEN enzyme activity. Hereditary mutations of the PTEN gene are the causes of a rare genetic disease called Cowden's disease. Cowden's disease patients are predisposed to developing skin, thyroid, and breast cancers. In laboratory conditions, increasing the abundance of PTEN in tumour cells such as brain and prostate tumour cells can suppress their growth, hence its role as a tumour suppressor. In addition to its role as a tumour suppressor, PTEN controls cancer cell spreading. Although much is known about the involvement of PTEN in cancer formation and the spreading of cancer cells, how PTEN suppresses tumour cell growth and spreading is not fully understood. The enzyme activity of PTEN enhances the removal of a chemical group called phosphate group from proteins and the fat-soluble compounds called phospholipids in the cell membrane. The ability of PTEN to suppress cell growth and spreading is due to its enzyme activity. However, exactly how the enzyme activity of PTEN is regulated is not well understood. In order for PTEN to efficiently enhance the removal of phosphate group from specific cellular proteins and phospholipids, PTEN needs to be located in close vicinity to these proteins and phospholipids. However, exactly how PTEN moves to the locations where these proteins and phospholipids are present remains elusive. This proposal aims at studying the regulation of PTEN enzyme activity and movement inside the cells. Results of the proposed studies will shed new light on how PTEN gene mutations contribute to cancer formation and the spreading of cancer cells and may facilitate the search for the cure of cancers.Read moreRead less