DNA – Page 6 – Oral Cancer News

Liverpool scientists working on vaccine for mouth cancer

Source: www.liverpoolecho.co.uk Author: Liza Williams ONE central project the scientists and doctors are working on is a vaccine for mouth cancer. Liverpool researchers have found some cases are caused by the HPV virus – the same bug which causes cervical cancer. They have discovered that two-thirds of tonsil cancer tumour samples showed evidence of the HPV-16 gene. The work is particularly important because the researchers are also seeing the rates of tonsil cancer doubling in non-smokers and non-drinkers – two of the main causes of the disease. They have found a DNA test helps to predict whether a patient has HPV. This could be used to decide which treatment is best for the patient, because both chemo and radiotherapy are more successful in patients with the virus. They are now developing a clinical trial for a HPV vaccine for head and neck cancer, like the jab given to teenage girls to prevent cervical cancer.

Oral Cancer Foundation News Team - A2010-01-04T08:31:39-07:00January, 2010|Oral Cancer News|

Scientists decode entire genetic code of cancer

Source: www.popsci.com Author: Jeremy Hsu And cigarette smokers get a free mutation in every pack In a major step toward understanding cancer, one of the biggest problems bedeviling modern medicine, scientists have now cracked the genetic code for two of the most common cancers. This marks just the beginning of an international effort to catalog all the genes that go wrong among the many types of human cancer, the BBC reports. Cracking the Cancer Code A cluster of breast cancer cells, with blue ones marking actively growing cells and yellow marking dying cells. Could scientists crack their code next? Too much time spent under the sun apparently leads to most of the 30,000 mutations contained within the DNA code for melanoma, or skin cancer. Outside experts told the BBC that no previous study has managed to link specific mutations to their causes. Wellcome Trust scientists also found more than 23,000 errors in the lung cancer DNA code, with most caused by cigarette smoke exposure. A typical smoker might get one new mutation, possibly harmless but also possibly a cancer trigger, for every 15 cigarettes that they smoke. The new cancer maps could lead to better blood tests for diagnosing the respective cancers, as well as better targeted drugs. Blood tests might even reveal the DNA patterns that suggest cancer lies on the horizon. The International Cancer Genome Consortium still expects to spend hundreds of thousands of dollars in cracking the code of the many human cancers. The U.S. has the [...]

Oral Cancer Foundation News Team - A2009-12-17T19:52:17-07:00December, 2009|Oral Cancer News|

Microarray technologies in the diagnosis and treatment of head and neck cancer

Source: emedicine.medscape.com Authors: Perminder S Parmar, MD et al. Introduction Since the draft sequence of the human genome was published in 2001 (Lander, 2001), the Cancer Genome Anatomy Project index of tumor genes has classified more than 40,000 genes directly or indirectly involved in one or more cancers (Strausberg, 2001; Strausberg, 2000). Conventional techniques of gene investigation in cancer rely on the identification of single genetic alterations associated with disease. This has proven to be both time consuming and cost ineffective. The introduction of complementary DNA (cDNA) microarray technology in 1995 (Schena, 1995) has helped to facilitate the identification and classification of DNA sequence information and the assignment of functions to these new genes by allowing investigators to analyze expression of thousands of genes simultaneously in a single experiment. Microarrays are a significant advance because they contain a very large number of genes and because of their small size. Therefore, microarrays are useful when one wants to survey a large number of genes quickly or when the study sample is small. Microarrays may be used to assay gene expression within a single sample or to compare gene expression in 2 different cell types or tissue samples, such as in healthy and diseased tissue. Because a microarray can be used to examine the expression of hundreds or thousands of genes at once, it promises to revolutionize the way gene expression is examined. Methods DNA microarrays are small solid supports onto which the sequences from thousands of different genes are attached at [...]

Oral Cancer Foundation News Team - A2009-11-06T21:36:37-07:00November, 2009|Oral Cancer News|

At our throats

Source: www.forbes.com Author: Matthew Herper Oncologist Maura Gillison was looking for patients with tonsil cancer for a clinical study several years ago. The first enlisted was a malpractice lawyer, followed by a doctor, then a scientist. She joked to a colleague that all she needed was a rear admiral. In walked a member of the military brass. All were in their 30s, 40s and 50s. People in their prime didn't used to get throat tumors. Head-and-neck cancer, as doctors call it, was a disease of older problem drinkers who also chain-smoked (more men than women). Years of exposure to scotch and Lucky Strikes would damage the DNA of cells lining the throat, leading to cancer. But Gillison, 44, a professor at Ohio State University, was among the first researchers to make a startling realization: The old cigarettes-and-alcohol form of the disease was being eclipsed by a new form, caused by the same human papilloma virus (HPV) that causes cervical cancer. The tumors grow in the tonsils or in the tissue that remains after tonsillectomy. The only good news is that the prognosis for these patients is better than for the old disease. Gillison and researchers at the National Cancer Institute estimate that 4,000 people, 75% of them men, develop this new form of throat cancer annually. That's only a tenth of head-and-neck cases, but it's half as many people as get cervical cancer in the U.S. More worrisome, Gillison's work shows HPV tonsil cancer is increasing at a rate of [...]

Oral Cancer Foundation News Team - A2009-10-15T13:20:48-07:00October, 2009|Oral Cancer News|

DNA test could be key to targeting treatments for head and neck cancer

Source: news.biocompare.com Author: staff It is estimated that more than 7,000 people are diagnosed with head and neck cancer each year in the UK and approximately 3,500 cases result in death. These cancers include tumours of the mouth, lips, throat and voice-box, and some have been linked to the sexually transmitted infection, HPV-16. Scientists at Liverpool analysed the DNA of more than 90 cancerous tissue samples to look for genes that indicated infection. The team found that nearly two thirds of tonsil tumour samples showed evidence of the HPV-16 gene. It is thought that chemical alterations in the virus's DNA trigger the production of proteins that can alter the rate at which cells grow and repair. This strongly increases the possibility of subsequent cancer development. Recent studies have found, however, that patients who have the HPV infection when they are diagnosed with cancer, respond better to chemotherapy or radiation therapy than those that do not have the infection. The work will be presented at the National Cancer Research Institute's (NCRI) Cancer Conference in Birmingham today. Mr Richard Shaw, from the School of Cancer Studies, explains: "Recent evidence demonstrates the possible involvement of HPV in the development of tonsil cancer, particularly in non-smokers. Interestingly, the treatment efficiency of chemotherapy and radiation, seems to differ between HPV positive and negative cases. We also need to find out why only a small percentage of people with this common infection develop this cancer. Our study, however, gives us a new lead towards a risk [...]

Oral Cancer Foundation News Team - A2009-10-13T21:04:03-07:00October, 2009|Oral Cancer News|

Identification of highly radiosensitive patients may lead to side effect-free radiotherapy

Source: www.ecancermedicalscience.com Author: staff An international group of scientists has taken the first step on the road to targeting radiotherapy dosage to individual patients by means of their genetic characteristics, a radiation oncologist told Europe’s largest cancer congress, ECCO 15 – ESMO 34, in Berlin today. Professor Dirk de Ruysscher, from Maastricht University Medical Centre, Maastricht, The Netherlands, said that his team’s work might provide the basis for personalised radiotherapy in which, with a simple blood test, doctors may be able to select the optimal radiation dose for a particular patient. The team of scientists from The Netherlands, Belgium, Germany, and Canada studied a group of patients with hypersensitivity to radiation therapy, drawn from the largest world-wide database available – the European Union-funded Genetic pathways for the prediction of the effect of irradiation (GENEPI) study, which integrates biological material with patient data and treatment specifications. The database included information from more than 8000 European patients. “Part of this project is the establishment of a sub-database in which very rare patient characteristics are brought together with the hypothesis that their genetic traits will enable the characterisation of molecular pathways related to radio-sensitivity,” explained Professor de Ruysscher. “A major problem for radiation oncologists at present is that we are bound by the need to avoid damage to normal tissues. This means that the dose of radiation generally used is governed by the response of the most radiosensitive patients, and this may lead to many patients receiving lower than optimal doses, hence affecting [...]

Oral Cancer Foundation News Team - A2009-09-25T07:51:01-07:00September, 2009|Oral Cancer News|

Perceptronix Reports Clinical Study Underway to Evaluate OralAdvance(TM) for Early Detection of Oral Cancer

Source: www.earthtimes.org Author: press release Perceptronix Medical Inc. announces that a clinical study of OralAdvance(TM), a test for the early detection of oral cancer, is now underway. The clinical study will assess the performance of OralAdvance(TM) compared to the gold standard biopsy and histology for its ability to differentiate between visually suspicious oral lesions with cancer or pre-cancer and visually suspicious benign oral lesions. "Unlike many other types of cancer, the incidence and mortality rates of oral cancer have not shown significant improvement over the past 30 years. By the time most oral cancers are diagnosed, they are already symptomatic late-stage disease. At Perceptronix we are dedicated to changing this paradigm towards early detection for better patient outcomes," says Dr. Bojana Turic, President and CEO of Perceptronix. Patients for the blinded study will be recruited from the BC Cancer Agency's Vancouver and Fraser Valley Centres. "We are pleased to be able to participate in the evaluation of the test in a clinical setting with technology that was developed in partnership with scientists at the BC Cancer Agency's Research Centre, and we are hopeful that the test will have a positive impact on the early detection of oral cancer," says Dr. Allan Hovan (Provincial Professional Practice Leader, Program in Oral Oncology/Dentistry, BC Cancer Agency). Currently, the death rate for oral cancer is higher than that of cervical cancer, Hodgkin's disease, cancer of the brain, liver, testes, kidney, or malignant melanoma. High death rate associated with oral cancer could be reduced significantly [...]

Oral Cancer Foundation News Team - A2009-05-08T18:56:15-07:00May, 2009|Oral Cancer News|

HPV data may aid vaccine’s effectiveness

Source: health.usnews.com Author: staff The majority of invasive cervical cancers in New Mexico in the 1980s and 1990s contained DNA from human papillomavirus type 16 (HPV16) and HPV type 18 (HPV18), says a new study. It also found that women diagnosed with HPV16- or HPV18-positive cancers were an average of five years younger than those diagnosed with cancers associated with other HPV types. The HPV vaccine (Gardasil) protects against infections caused by HPV16 and HPV18, so the new findings may have implications for future cancer screening programs, the researchers said. The researchers analyzed U.S. data in the Surveillance, Epidemiology and End Results registry and identified 1,213 cases of in situ cervical cancer diagnosed between 1980 and 1999, as well as 808 cases of invasive cervical cancer diagnosed between 1980 and 1999 in New Mexico. HPV16 DNA was found in 53.2 percent of invasive cervical cancers, HPV18 DNA was found in 13.1 percent, and HPV45 DNA in 6.1 percent. HPV16 DNA was found in 56.3 percent of in situ cervical cancers, HPV31 DNA in 12.6 percent, and HPV33 DNA in 8 percent. Patients' median age at diagnosis of invasive cancer with HPV16 and HPV18 was 48.1 years, and 45.9 years, respectively. Median age at diagnosis of invasive cancer with other HPV genotypes was 52.3 years. The study is in the March 24 online issue of the Journal of the National Cancer Institute. "To our knowledge, this is the largest study of its kind conducted in a U.S. population," wrote a team [...]

Oral Cancer Foundation News Team - A2009-04-13T09:08:21-07:00April, 2009|Oral Cancer News|

Discovery may result in new test to determine predisposition to cancer

Source: www.biocompare.com Author: staff Researchers at UCLA's Jonsson Comprehensive Cancer Center have developed an assay that may be used to help identify new genes that can predict a predisposition to cancer. The study, published in the April issue of Radiation Research, was done in yeast and mammalian cells. Cancer cells show persistent genetic instability and the researchers, led by Robert Schiestl, have discovered a mechanism that switches on that genetic instability. If they can uncover and understand the molecular pathways at work in promoting genetic instability, they may be able to develop ways to switch that mechanism off, restoring stability. "We all have several hundred cells in our body that go crazy every day, and they're taken out by our immune system," said Schiestl, a professor of pathology, radiation oncology and environmental health sciences and a Jonsson Cancer Center scientist. "What's important is that those cells don't grow and spread and invade other regions of our body. Cancer cells are able to grow, spread and invade because the continued genetic instability can disturb the cellular program and create a growth advantage. Unfortunately, the immune system is not very effective at taking cancer cells out." The assay determines the efficiency of the repair mechanism when DNA suffers a double-strand break, when both strands in the double helix are severed. These breaks cause genetic instability and are particularly dangerous because they can lead to genome rearrangements or deletions of certain genes that, when gone, result in cancer. "Every cell has double strand [...]

Oral Cancer Foundation News Team - A2009-04-02T13:52:45-07:00April, 2009|Oral Cancer News|

Genetic Changes Outside Nuclear DNA suspected to trigger more than half of all cancers

Source: www.newswise.com Author: staff A buildup of chemical bonds on certain cancer-promoting genes, a process known as hypermethylation, is widely known to render cells cancerous by disrupting biological brakes on runaway growth. Now, Johns Hopkins scientists say the reverse process — demethylation — which wipes off those chemical bonds may also trigger more than half of all cancers. One potential consequence of the new research is that demethylating drugs now used to treat some cancers may actually cause new cancers as a side effect. “It’s much too early to say for certain, but some patients could be at risk for additional primary tumors, and we may find that they need a molecular profile of their cancer before starting demethylating therapy,” says Joseph Califano, M.D., professor of otolaryngology–head and neck surgery and oncology at Johns Hopkins. The findings, based on studies of normal and cancer cells from human mouth, nose and throat tissue, provide more evidence that important regulators of gene activity occur outside as well as inside DNA in a cell’s nucleus. “While cancer-causing and other mutations alter vital protein-making pathways by rewriting the gene’s DNA code, epigenetic changes affect genes without changing the code itself. The new studies tell us that such changes occur not only when methyl groups bond to a gene’s on-off switch, but also when they come unglued,” says Califano. Califano says sporadic reports of demethylation as a tool in activating cancer-promoting genes led his team to develop a systematic way to discover these epigenetic changes [...]

Oral Cancer Foundation News Team - A2009-03-27T13:11:41-07:00March, 2009|Oral Cancer News|